Skip to content

Reference architecture: up to 3,000 users

DETAILS: Tier: Premium, Ultimate Offering: Self-managed

This page describes the GitLab reference architecture designed for the load of up to 3,000 users with notable headroom.

This architecture is the smallest one available with HA built in. If you require HA but have a lower user count or total load the Supported Modifications for lower user counts section details how to reduce this architecture's size while maintaining HA.

For a full list of reference architectures, see Available reference architectures.

  • Target Load: 60 RPS, Web: 6 RPS, Git (Pull): 6 RPS, Git (Push): 1 RPS
  • High Availability: Yes, although Praefect needs a third-party PostgreSQL solution
  • Estimated Costs: See cost table
  • Cloud Native Hybrid Alternative: Yes
  • Unsure which Reference Architecture to use? Go to this guide for more info.
Service Nodes Configuration GCP AWS Azure
External load balancing node3 1 2 vCPU, 1.8 GB memory n1-highcpu-2 c5.large F2s v2
Redis2 3 2 vCPU, 7.5 GB memory n1-standard-2 m5.large D2s v3
Consul1 + Sentinel2 3 2 vCPU, 1.8 GB memory n1-highcpu-2 c5.large F2s v2
PostgreSQL1 3 2 vCPU, 7.5 GB memory n1-standard-2 m5.large D2s v3
PgBouncer1 3 2 vCPU, 1.8 GB memory n1-highcpu-2 c5.large F2s v2
Internal load balancing node3 1 2 vCPU, 1.8 GB memory n1-highcpu-2 c5.large F2s v2
Gitaly5 3 4 vCPU, 15 GB memory6 n1-standard-4 m5.xlarge D4s v3
Praefect5 3 2 vCPU, 1.8 GB memory n1-highcpu-2 c5.large F2s v2
Praefect PostgreSQL1 1+ 2 vCPU, 1.8 GB memory n1-highcpu-2 c5.large F2s v2
Sidekiq7 2 4 vCPU, 15 GB memory n1-standard-4 m5.xlarge D2s v3
GitLab Rails7 3 8 vCPU, 7.2 GB memory n1-highcpu-8 c5.2xlarge F8s v2
Monitoring node 1 2 vCPU, 1.8 GB memory n1-highcpu-2 c5.large F2s v2
Object storage4 - - - - -
  1. Can be optionally run on reputable third-party external PaaS PostgreSQL solutions. See Provide your own PostgreSQL instance for more information.
  2. Can be optionally run on reputable third-party external PaaS Redis solutions. See Provide your own Redis instance for more information.
  3. Can be optionally run on reputable third-party load balancing services (LB PaaS). See Recommended cloud providers and services for more information.
  4. Should be run on reputable Cloud Provider or Self Managed solutions. See Configure the object storage for more information.
  5. Gitaly Cluster provides the benefits of fault tolerance, but comes with additional complexity of setup and management. Review the existing technical limitations and considerations before deploying Gitaly Cluster. If you want sharded Gitaly, use the same specs listed above for Gitaly.
  6. Gitaly specifications are based on high percentiles of both usage patterns and repository sizes in good health. However, if you have large monorepos (larger than several gigabytes) or additional workloads these can significantly impact Git and Gitaly performance and further adjustments will likely be required.
  7. Can be placed in Auto Scaling Groups (ASGs) as the component doesn't store any stateful data. However, for GitLab Rails certain processes like migrations and Mailroom should be run on only one node.

NOTE: For all PaaS solutions that involve configuring instances, it is strongly recommended to implement a minimum of three nodes in three different availability zones to align with resilient cloud architecture practices.

@startuml 3k
skinparam linetype ortho

card "**External Load Balancer**" as elb #6a9be7
card "**Internal Load Balancer**" as ilb #9370DB

together {
  collections "**GitLab Rails** x3" as gitlab #32CD32
  collections "**Sidekiq** x2" as sidekiq #ff8dd1
}

together {
  card "**Prometheus**" as monitor #7FFFD4
  collections "**Consul** x3" as consul #e76a9b
}

card "Gitaly Cluster" as gitaly_cluster {
  collections "**Praefect** x3" as praefect #FF8C00
  collections "**Gitaly** x3" as gitaly #FF8C00
  card "**Praefect PostgreSQL***\n//Non fault-tolerant//" as praefect_postgres #FF8C00

  praefect -[#FF8C00]-> gitaly
  praefect -[#FF8C00]> praefect_postgres
}

card "Database" as database {
  collections "**PGBouncer** x3" as pgbouncer #4EA7FF
  card "**PostgreSQL** //Primary//" as postgres_primary #4EA7FF
  collections "**PostgreSQL** //Secondary// x2" as postgres_secondary #4EA7FF

  pgbouncer -[#4EA7FF]-> postgres_primary
  postgres_primary .[#4EA7FF]> postgres_secondary
}

card "Redis" as redis {
  collections "**Redis** x3" as redis_nodes #FF6347
}

cloud "**Object Storage**" as object_storage #white

elb -[#6a9be7]-> gitlab
elb -[#6a9be7,norank]--> monitor

gitlab -[#32CD32,norank]--> ilb
gitlab -[#32CD32]r-> object_storage
gitlab -[#32CD32]----> redis
gitlab .[#32CD32]----> database
gitlab -[hidden]-> monitor
gitlab -[hidden]-> consul

sidekiq -[#ff8dd1,norank]--> ilb
sidekiq -[#ff8dd1]r-> object_storage
sidekiq -[#ff8dd1]----> redis
sidekiq .[#ff8dd1]----> database
sidekiq -[hidden]-> monitor
sidekiq -[hidden]-> consul

ilb -[#9370DB]--> gitaly_cluster
ilb -[#9370DB]--> database
ilb -[hidden]--> redis
ilb -[hidden]u-> consul
ilb -[hidden]u-> monitor

consul .[#e76a9b]u-> gitlab
consul .[#e76a9b]u-> sidekiq
consul .[#e76a9b]r-> monitor
consul .[#e76a9b]-> database
consul .[#e76a9b]-> gitaly_cluster
consul .[#e76a9b,norank]--> redis

monitor .[#7FFFD4]u-> gitlab
monitor .[#7FFFD4]u-> sidekiq
monitor .[#7FFFD4]> consul
monitor .[#7FFFD4]-> database
monitor .[#7FFFD4]-> gitaly_cluster
monitor .[#7FFFD4,norank]--> redis
monitor .[#7FFFD4]> ilb
monitor .[#7FFFD4,norank]u--> elb

@enduml

Requirements

Before starting, see the requirements for reference architectures.

Testing methodology

The 3k architecture is designed to cover a large majority of workflows and is regularly smoke and performance tested by the Quality Engineering team against the following endpoint throughput targets:

  • API: 60 RPS
  • Web: 6 RPS
  • Git (Pull): 6 RPS
  • Git (Push): 1 RPS

The above targets were selected based on real customer data of total environmental loads corresponding to the user count, including CI and other workloads along with additional substantial headroom added.

If you have metrics to suggest that you have regularly higher throughput against the above endpoint targets, large monorepos or notable additional workloads these can notably impact the performance environment and further adjustments may be required. If this applies to you, we strongly recommended referring to the linked documentation as well as reaching out to your Customer Success Manager or our Support team for further guidance.

Testing is done regularly via our GitLab Performance Tool (GPT) and its dataset, which is available for anyone to use. The results of this testing are available publicly on the GPT wiki. For more information on our testing strategy refer to this section of the documentation.

The load balancers used for testing were HAProxy for Linux package environments or equivalent Cloud Provider services via NGINX Ingress for Cloud Native Hybrids. Note that these selections do not represent a specific requirement or recommendation as most reputable load balancers are expected to work.

Setup components

To set up GitLab and its components to accommodate up to 3,000 users:

  1. Configure the external load balancer to handle the load balancing of the GitLab application services nodes.
  2. Configure the internal load balancer. to handle the load balancing of GitLab application internal connections.
  3. Configure Redis.
  4. Configure Consul and Sentinel.
  5. Configure PostgreSQL, the database for GitLab.
  6. Configure PgBouncer.
  7. Configure Gitaly Cluster, provides access to the Git repositories.
  8. Configure Sidekiq.
  9. Configure the main GitLab Rails application to run Puma, Workhorse, GitLab Shell, and to serve all frontend requests (which include UI, API, and Git over HTTP/SSH).
  10. Configure Prometheus to monitor your GitLab environment.
  11. Configure the object storage used for shared data objects.
  12. Configure advanced search (optional) for faster, more advanced code search across your entire GitLab instance.

The servers start on the same 10.6.0.0/24 private network range, and can connect to each other freely on these addresses.

The following list includes descriptions of each server and its assigned IP:

  • 10.6.0.10: External Load Balancer
  • 10.6.0.11: Consul/Sentinel 1
  • 10.6.0.12: Consul/Sentinel 2
  • 10.6.0.13: Consul/Sentinel 3
  • 10.6.0.21: PostgreSQL primary
  • 10.6.0.22: PostgreSQL secondary 1
  • 10.6.0.23: PostgreSQL secondary 2
  • 10.6.0.31: PgBouncer 1
  • 10.6.0.32: PgBouncer 2
  • 10.6.0.33: PgBouncer 3
  • 10.6.0.20: Internal Load Balancer
  • 10.6.0.61: Redis Primary
  • 10.6.0.62: Redis Replica 1
  • 10.6.0.63: Redis Replica 2
  • 10.6.0.51: Gitaly 1
  • 10.6.0.52: Gitaly 2
  • 10.6.0.93: Gitaly 3
  • 10.6.0.131: Praefect 1
  • 10.6.0.132: Praefect 2
  • 10.6.0.133: Praefect 3
  • 10.6.0.141: Praefect PostgreSQL 1 (non HA)
  • 10.6.0.71: Sidekiq 1
  • 10.6.0.72: Sidekiq 2
  • 10.6.0.41: GitLab application 1
  • 10.6.0.42: GitLab application 2
  • 10.6.0.43: GitLab application 3
  • 10.6.0.81: Prometheus

Configure the external load balancer

In a multi-node GitLab configuration, you'll need a load balancer to route traffic to the application servers.

The specifics on which load balancer to use, or its exact configuration is beyond the scope of GitLab documentation. It is expected however that any reputable load balancer should work and as such this section will focus on the specifics of what to configure for your load balancer of choice.

Balancing algorithm

We recommend that a least-connection load balancing algorithm or equivalent is used wherever possible to ensure equal spread of calls to the nodes and good performance.

We don't recommend the use of round-robin algorithms as they are known to not spread connections equally in practice.

Readiness checks

Ensure the external load balancer only routes to working services with built in monitoring endpoints. The readiness checks all require additional configuration on the nodes being checked, otherwise, the external load balancer will not be able to connect.

Ports

The basic ports to be used are shown in the table below.

LB Port Backend Port Protocol
80 80 HTTP (1)
443 443 TCP or HTTPS (1) (2)
22 22 TCP
  • (1): Web terminal support requires your load balancer to correctly handle WebSocket connections. When using HTTP or HTTPS proxying, this means your load balancer must be configured to pass through the Connection and Upgrade hop-by-hop headers. See the web terminal integration guide for more details.
  • (2): When using HTTPS protocol for port 443, you will need to add an SSL certificate to the load balancers. If you wish to terminate SSL at the GitLab application server instead, use TCP protocol.

If you're using GitLab Pages with custom domain support you will need some additional port configurations. GitLab Pages requires a separate virtual IP address. Configure DNS to point the pages_external_url from /etc/gitlab/gitlab.rb at the new virtual IP address. See the GitLab Pages documentation for more information.

LB Port Backend Port Protocol
80 Varies (1) HTTP
443 Varies (1) TCP (2)
  • (1): The backend port for GitLab Pages depends on the gitlab_pages['external_http'] and gitlab_pages['external_https'] setting. See GitLab Pages documentation for more details.
  • (2): Port 443 for GitLab Pages should always use the TCP protocol. Users can configure custom domains with custom SSL, which would not be possible if SSL was terminated at the load balancer.

Alternate SSH Port

Some organizations have policies against opening SSH port 22. In this case, it may be helpful to configure an alternate SSH hostname that allows users to use SSH on port 443. An alternate SSH hostname will require a new virtual IP address compared to the other GitLab HTTP configuration above.

Configure DNS for an alternate SSH hostname such as altssh.gitlab.example.com.

LB Port Backend Port Protocol
443 22 TCP

SSL

The next question is how you will handle SSL in your environment. There are several different options:

Application node terminates SSL

Configure your load balancer to pass connections on port 443 as TCP rather than HTTP(S) protocol. This will pass the connection to the application node's NGINX service untouched. NGINX will have the SSL certificate and listen on port 443.

See the HTTPS documentation for details on managing SSL certificates and configuring NGINX.

Load balancer terminates SSL without backend SSL

Configure your load balancer to use the HTTP(S) protocol rather than TCP. The load balancer will then be responsible for managing SSL certificates and terminating SSL.

Since communication between the load balancer and GitLab will not be secure, there is some additional configuration needed. See the proxied SSL documentation for details.

Load balancer terminates SSL with backend SSL

Configure your load balancers to use the 'HTTP(S)' protocol rather than 'TCP'. The load balancers will be responsible for managing SSL certificates that end users will see.

Traffic will also be secure between the load balancers and NGINX in this scenario. There is no need to add configuration for proxied SSL since the connection will be secure all the way. However, configuration will need to be added to GitLab to configure SSL certificates. See the HTTPS documentation for details on managing SSL certificates and configuring NGINX.

Configure the internal load balancer

The Internal Load Balancer is used to balance any internal connections the GitLab environment requires such as connections to PgBouncer and Praefect (Gitaly Cluster).

It's a separate node from the External Load Balancer and shouldn't have any access externally.

The following IP will be used as an example:

  • 10.6.0.40: Internal Load Balancer

Here's how you could do it with HAProxy:

global
    log /dev/log local0
    log localhost local1 notice
    log stdout format raw local0

defaults
    log global
    default-server inter 10s fall 3 rise 2
    balance leastconn

frontend internal-pgbouncer-tcp-in
    bind *:6432
    mode tcp
    option tcplog

    default_backend pgbouncer

frontend internal-praefect-tcp-in
    bind *:2305
    mode tcp
    option tcplog
    option clitcpka

    default_backend praefect

backend pgbouncer
    mode tcp
    option tcp-check

    server pgbouncer1 10.6.0.31:6432 check
    server pgbouncer2 10.6.0.32:6432 check
    server pgbouncer3 10.6.0.33:6432 check

backend praefect
    mode tcp
    option tcp-check
    option srvtcpka

    server praefect1 10.6.0.131:2305 check
    server praefect2 10.6.0.132:2305 check
    server praefect3 10.6.0.133:2305 check

Refer to your preferred Load Balancer's documentation for further guidance.

Balancing algorithm

We recommend that a least-connection load balancing algorithm or equivalent is used wherever possible to ensure equal spread of calls to the nodes and good performance.

We don't recommend the use of round-robin algorithms as they are known to not spread connections equally in practice.

Configure Redis

Using Redis in scalable environment is possible using a Primary x Replica topology with a Redis Sentinel service to watch and automatically start the failover procedure.

NOTE: Multi-node Redis must be deployed in an odd number of 3 nodes or more to ensure Redis Sentinel can take votes as part of a quorum. This does not apply when configuring Redis externally, such as a cloud provider service.

NOTE: Redis is primarily single threaded and doesn't significantly benefit from an increase in CPU cores. Refer to the scaling documentation for more information.

Redis requires authentication if used with Sentinel. See Redis Security documentation for more information. We recommend using a combination of a Redis password and tight firewall rules to secure your Redis service. You are highly encouraged to read the Redis Sentinel documentation before configuring Redis with GitLab to fully understand the topology and architecture.

In this section, you'll be guided through configuring an external Redis instance to be used with GitLab. The following IPs will be used as an example:

  • 10.6.0.61: Redis Primary
  • 10.6.0.62: Redis Replica 1
  • 10.6.0.63: Redis Replica 2

Provide your own Redis instance

You can optionally use a third party external service for the Redis instance with the following guidance:

  • A reputable provider or solution should be used for this. Google Memorystore and AWS ElastiCache are known to work.
  • Redis Cluster mode is specifically not supported, but Redis Standalone with HA (Redis Sentinel) is supported.
  • You must set the Redis eviction mode according to your setup.

For more information, see Recommended cloud providers and services.

Standalone Redis using the Linux package

This is the section where we install and set up the new Redis instances.

The requirements for a Redis setup are the following:

  1. All Redis nodes must be able to talk to each other and accept incoming connections over Redis (6379) and Sentinel (26379) ports (unless you change the default ones).
  2. The server that hosts the GitLab application must be able to access the Redis nodes.
  3. Protect the nodes from access from external networks (Internet), using a firewall.

Both the primary and replica Redis nodes need the same password defined in redis['password']. At any time during a failover, the Sentinels can reconfigure a node and change its status from primary to replica (and vice versa).

Configuring the primary Redis instance

  1. SSH in to the Primary Redis server.

  2. Download and install the Linux package of your choice. Be sure to both follow only installation steps 1 and 2 on the page, and to select the correct Linux package, with the same version and type (Community or Enterprise editions) as your current install.

  3. Edit /etc/gitlab/gitlab.rb and add the contents:

    # Specify server role as 'redis_master_role' and enable Consul agent
roles(['redis_master_role', 'consul_role'])

# IP address pointing to a local IP that the other machines can reach to.
# You can also set bind to '0.0.0.0' which listen in all interfaces.
# If you really need to bind to an external accessible IP, make
# sure you add extra firewall rules to prevent unauthorized access.
redis['bind'] = '10.6.0.61'

# Define a port so Redis can listen for TCP requests which will allow other
# machines to connect to it.
redis['port'] = 6379

# Set up password authentication for Redis (use the same password in all nodes).
redis['password'] = 'redis-password-goes-here'

## Enable service discovery for Prometheus
consul['monitoring_service_discovery'] =  true

## The IPs of the Consul server nodes
## You can also use FQDNs and intermix them with IPs
consul['configuration'] = {
   retry_join: %w(10.6.0.11 10.6.0.12 10.6.0.13),
}

# Set the network addresses that the exporters will listen on
node_exporter['listen_address'] = '0.0.0.0:9100'
redis_exporter['listen_address'] = '0.0.0.0:9121'
redis_exporter['flags'] = {
     'redis.addr' => 'redis://10.6.0.61:6379',
     'redis.password' => 'redis-password-goes-here',
}

# Prevent database migrations from running on upgrade automatically
gitlab_rails['auto_migrate'] = false

  4. Copy the /etc/gitlab/gitlab-secrets.json file from the first Linux package node you configured and add or replace the file of the same name on this server. If this is the first Linux package node you are configuring then you can skip this step.

  5. Reconfigure GitLab for the changes to take effect.

You can specify multiple roles, like sentinel and Redis, as: roles ['redis_sentinel_role', 'redis_master_role']. Read more about roles.

You can list the current Redis Primary, Replica status by using:

/opt/gitlab/embedded/bin/redis-cli -h <host> -a 'redis-password-goes-here' info replication

Show running GitLab services by using:

gitlab-ctl status

The output should be similar to the following:

run: consul: (pid 30043) 76863s; run: log: (pid 29691) 76892s
run: logrotate: (pid 31152) 3070s; run: log: (pid 29595) 76908s
run: node-exporter: (pid 30064) 76862s; run: log: (pid 29624) 76904s
run: redis: (pid 30070) 76861s; run: log: (pid 29573) 76914s
run: redis-exporter: (pid 30075) 76861s; run: log: (pid 29674) 76896s

Configuring the replica Redis instances

  1. SSH in to the replica Redis server.

  2. Download and install the Linux package of your choice. Be sure to both follow only installation steps 1 and 2 on the page, and to select the correct Linux package, with the same version and type (Community or Enterprise editions) as your current install.

  3. Edit /etc/gitlab/gitlab.rb and add the contents:

    # Specify server role as 'redis_replica_role' and enable Consul agent
roles(['redis_replica_role', 'consul_role'])

# IP address pointing to a local IP that the other machines can reach to.
# You can also set bind to '0.0.0.0' which listen in all interfaces.
# If you really need to bind to an external accessible IP, make
# sure you add extra firewall rules to prevent unauthorized access.
redis['bind'] = '10.6.0.62'

# Define a port so Redis can listen for TCP requests which will allow other
# machines to connect to it.
redis['port'] = 6379

# The same password for Redis authentication you set up for the primary node.
redis['password'] = 'redis-password-goes-here'

# The IP of the primary Redis node.
redis['master_ip'] = '10.6.0.61'

# Port of primary Redis server, uncomment to change to non default. Defaults
# to `6379`.
#redis['master_port'] = 6379

## Enable service discovery for Prometheus
consul['monitoring_service_discovery'] =  true

## The IPs of the Consul server nodes
## You can also use FQDNs and intermix them with IPs
consul['configuration'] = {
   retry_join: %w(10.6.0.11 10.6.0.12 10.6.0.13),
}

# Set the network addresses that the exporters will listen on
node_exporter['listen_address'] = '0.0.0.0:9100'
redis_exporter['listen_address'] = '0.0.0.0:9121'
redis_exporter['flags'] = {
     'redis.addr' => 'redis://10.6.0.62:6379',
     'redis.password' => 'redis-password-goes-here',
}

# Prevent database migrations from running on upgrade automatically
gitlab_rails['auto_migrate'] = false

  4. Copy the /etc/gitlab/gitlab-secrets.json file from the first Linux package node you configured and add or replace the file of the same name on this server. If this is the first Linux package node you are configuring then you can skip this step.

  5. Reconfigure GitLab for the changes to take effect.

  6. Go through the steps again for all the other replica nodes, and make sure to set up the IPs correctly.

You can specify multiple roles, like sentinel and Redis, as: roles(['redis_sentinel_role', 'redis_master_role']). Read more about roles.

These values don't have to be changed again in /etc/gitlab/gitlab.rb after a failover, as the nodes will be managed by the Sentinels, and even after a gitlab-ctl reconfigure, they will get their configuration restored by the same Sentinels.

Advanced configuration options are supported and can be added if needed.

Configure Consul and Sentinel

Now that the Redis servers are all set up, let's configure the Consul + Sentinel servers.

NOTE: Consul and Redis Sentinel must be deployed in an odd number of 3 nodes or more. This is to ensure the nodes can take votes as part of a quorum.

The following IPs will be used as an example:

  • 10.6.0.11: Consul/Sentinel 1
  • 10.6.0.12: Consul/Sentinel 2
  • 10.6.0.13: Consul/Sentinel 3

NOTE: If you're using an external Redis Sentinel instance, be sure to exclude the requirepass parameter from the Sentinel configuration. This parameter causes clients to report NOAUTH Authentication required.. Redis Sentinel 3.2.x doesn't support password authentication.

To configure the Sentinel:

  1. SSH in to the server that will host Consul/Sentinel.

  2. Download and install the Linux package of your choice. Be sure to both follow only installation steps 1 and 2 on the page, and to select the correct Linux package, with the same version and type (Community or Enterprise editions) as your current install.

  3. Edit /etc/gitlab/gitlab.rb and add the contents:

    roles(['redis_sentinel_role', 'consul_role'])

# Must be the same in every sentinel node
redis['master_name'] = 'gitlab-redis'

# The same password for Redis authentication you set up for the primary node.
redis['master_password'] = 'redis-password-goes-here'

# The IP of the primary Redis node.
redis['master_ip'] = '10.6.0.61'

# Define a port so Redis can listen for TCP requests which will allow other
# machines to connect to it.
redis['port'] = 6379

# Port of primary Redis server, uncomment to change to non default. Defaults
# to `6379`.
#redis['master_port'] = 6379

## Configure Sentinel
sentinel['bind'] = '10.6.0.11'

# Port that Sentinel listens on, uncomment to change to non default. Defaults
# to `26379`.
# sentinel['port'] = 26379

## Quorum must reflect the amount of voting sentinels it take to start a failover.
## Value must NOT be greater then the amount of sentinels.
##
## The quorum can be used to tune Sentinel in two ways:
## 1. If a the quorum is set to a value smaller than the majority of Sentinels
##    we deploy, we are basically making Sentinel more sensible to primary failures,
##    triggering a failover as soon as even just a minority of Sentinels is no longer
##    able to talk with the primary.
## 1. If a quorum is set to a value greater than the majority of Sentinels, we are
##    making Sentinel able to failover only when there are a very large number (larger
##    than majority) of well connected Sentinels which agree about the primary being down.s
sentinel['quorum'] = 2

## Consider unresponsive server down after x amount of ms.
# sentinel['down_after_milliseconds'] = 10000

## Specifies the failover timeout in milliseconds. It is used in many ways:
##
## - The time needed to re-start a failover after a previous failover was
##   already tried against the same primary by a given Sentinel, is two
##   times the failover timeout.
##
## - The time needed for a replica replicating to a wrong primary according
##   to a Sentinel current configuration, to be forced to replicate
##   with the right primary, is exactly the failover timeout (counting since
##   the moment a Sentinel detected the misconfiguration).
##
## - The time needed to cancel a failover that is already in progress but
##   did not produced any configuration change (REPLICAOF NO ONE yet not
##   acknowledged by the promoted replica).
##
## - The maximum time a failover in progress waits for all the replica to be
##   reconfigured as replicas of the new primary. However even after this time
##   the replicas will be reconfigured by the Sentinels anyway, but not with
##   the exact parallel-syncs progression as specified.
# sentinel['failover_timeout'] = 60000

## Enable service discovery for Prometheus
consul['monitoring_service_discovery'] =  true

## The IPs of the Consul server nodes
## You can also use FQDNs and intermix them with IPs
consul['configuration'] = {
   server: true,
   retry_join: %w(10.6.0.11 10.6.0.12 10.6.0.13),
}

# Set the network addresses that the exporters will listen on
node_exporter['listen_address'] = '0.0.0.0:9100'
redis_exporter['listen_address'] = '0.0.0.0:9121'

# Prevent database migrations from running on upgrade automatically
gitlab_rails['auto_migrate'] = false

  4. Copy the /etc/gitlab/gitlab-secrets.json file from the first Linux package node you configured and add or replace the file of the same name on this server. If this is the first Linux package node you are configuring then you can skip this step.

  5. Reconfigure GitLab for the changes to take effect.

  6. Go through the steps again for all the other Consul/Sentinel nodes, and make sure you set up the correct IPs.

A Consul leader is elected when the provisioning of the third Consul server is complete. Viewing the Consul logs sudo gitlab-ctl tail consul displays ...[INFO] consul: New leader elected: ....

You can list the current Consul members (server, client):

sudo /opt/gitlab/embedded/bin/consul members

You can verify the GitLab services are running:

sudo gitlab-ctl status

The output should be similar to the following:

run: consul: (pid 30074) 76834s; run: log: (pid 29740) 76844s
run: logrotate: (pid 30925) 3041s; run: log: (pid 29649) 76861s
run: node-exporter: (pid 30093) 76833s; run: log: (pid 29663) 76855s
run: sentinel: (pid 30098) 76832s; run: log: (pid 29704) 76850s

Configure PostgreSQL

In this section, you'll be guided through configuring a highly available PostgreSQL cluster to be used with GitLab.

Provide your own PostgreSQL instance

You can optionally use a third party external service for PostgreSQL.

A reputable provider or solution should be used for this. Google Cloud SQL and Amazon RDS are known to work. However, Amazon Aurora is incompatible with load balancing enabled by default from 14.4.0. See Recommended cloud providers and services for more information.

If you use a third party external service:

  1. Note that the HA Linux package PostgreSQL setup encompasses PostgreSQL, PgBouncer and Consul. All of these components would no longer be required when using a third party external service.
  2. Set up PostgreSQL according to the database requirements document.
  3. Set up a gitlab username with a password of your choice. The gitlab user needs privileges to create the gitlabhq_production database.
  4. Configure the GitLab application servers with the appropriate details. This step is covered in Configuring the GitLab Rails application.
  5. The number of nodes required to achieve HA may differ depending on the service compared to the Linux package and doesn't need to match accordingly.
  6. However, if Database Load Balancing via Read Replicas is desired for further improved performance it's recommended to follow the node count for the Reference Architecture.

Standalone PostgreSQL using the Linux package

The recommended Linux package configuration for a PostgreSQL cluster with replication and failover requires:

  • A minimum of three PostgreSQL nodes.

  • A minimum of three Consul server nodes.

  • A minimum of three PgBouncer nodes that track and handle primary database reads and writes.

  • Database Load Balancing enabled.

    A local PgBouncer service to be configured on each PostgreSQL node. Note that this is separate from the main PgBouncer cluster that tracks the primary.

The following IPs will be used as an example:

  • 10.6.0.21: PostgreSQL primary
  • 10.6.0.22: PostgreSQL secondary 1
  • 10.6.0.23: PostgreSQL secondary 2

First, make sure to install the Linux GitLab package on each node. Following the steps, install the necessary dependencies from step 1, and add the GitLab package repository from step 2. When installing GitLab in the second step, do not supply the EXTERNAL_URL value.

PostgreSQL nodes

  1. SSH in to one of the PostgreSQL nodes.

  2. Generate a password hash for the PostgreSQL username/password pair. This assumes you will use the default username of gitlab (recommended). The command will request a password and confirmation. Use the value that is output by this command in the next step as the value of <postgresql_password_hash>:

    sudo gitlab-ctl pg-password-md5 gitlab

  3. Generate a password hash for the PgBouncer username/password pair. This assumes you will use the default username of pgbouncer (recommended). The command will request a password and confirmation. Use the value that is output by this command in the next step as the value of <pgbouncer_password_hash>:

    sudo gitlab-ctl pg-password-md5 pgbouncer

  4. Generate a password hash for the PostgreSQL replication username/password pair. This assumes you will use the default username of gitlab_replicator (recommended). The command will request a password and a confirmation. Use the value that is output by this command in the next step as the value of <postgresql_replication_password_hash>:

    sudo gitlab-ctl pg-password-md5 gitlab_replicator

  5. Generate a password hash for the Consul database username/password pair. This assumes you will use the default username of gitlab-consul (recommended). The command will request a password and confirmation. Use the value that is output by this command in the next step as the value of <consul_password_hash>:

    sudo gitlab-ctl pg-password-md5 gitlab-consul

  6. On every database node, edit /etc/gitlab/gitlab.rb replacing values noted in the # START user configuration section:

    # Disable all components except Patroni, PgBouncer and Consul
roles(['patroni_role', 'pgbouncer_role'])

# PostgreSQL configuration
postgresql['listen_address'] = '0.0.0.0'

# Sets `max_replication_slots` to double the number of database nodes.
# Patroni uses one extra slot per node when initiating the replication.
patroni['postgresql']['max_replication_slots'] = 6

# Set `max_wal_senders` to one more than the number of replication slots in the cluster.
# This is used to prevent replication from using up all of the
# available database connections.
patroni['postgresql']['max_wal_senders'] = 7

# Prevent database migrations from running on upgrade automatically
gitlab_rails['auto_migrate'] = false

# Configure the Consul agent
consul['services'] = %w(postgresql)
## Enable service discovery for Prometheus
consul['monitoring_service_discovery'] =  true

# START user configuration
# Please set the real values as explained in Required Information section
#
# Replace PGBOUNCER_PASSWORD_HASH with a generated md5 value
postgresql['pgbouncer_user_password'] = '<pgbouncer_password_hash>'
# Replace POSTGRESQL_REPLICATION_PASSWORD_HASH with a generated md5 value
postgresql['sql_replication_password'] = '<postgresql_replication_password_hash>'
# Replace POSTGRESQL_PASSWORD_HASH with a generated md5 value
postgresql['sql_user_password'] = '<postgresql_password_hash>'

# Set up basic authentication for the Patroni API (use the same username/password in all nodes).
patroni['username'] = '<patroni_api_username>'
patroni['password'] = '<patroni_api_password>'

# Replace 10.6.0.0/24 with Network Address
postgresql['trust_auth_cidr_addresses'] = %w(10.6.0.0/24 127.0.0.1/32)

# Local PgBouncer service for Database Load Balancing
pgbouncer['databases'] = {
   gitlabhq_production: {
      host: "127.0.0.1",
      user: "pgbouncer",
      password: '<pgbouncer_password_hash>'
   }
}

# Set the network addresses that the exporters will listen on for monitoring
node_exporter['listen_address'] = '0.0.0.0:9100'
postgres_exporter['listen_address'] = '0.0.0.0:9187'

## The IPs of the Consul server nodes
## You can also use FQDNs and intermix them with IPs
consul['configuration'] = {
   retry_join: %w(10.6.0.11 10.6.0.12 10.6.0.13),
}
#
# END user configuration

PostgreSQL, with Patroni managing its failover, will default to use pg_rewind by default to handle conflicts. Like most failover handling methods, this has a small chance of leading to data loss. For more information, see the various Patroni replication methods.

  1. Copy the /etc/gitlab/gitlab-secrets.json file from the first Linux package node you configured and add or replace the file of the same name on this server. If this is the first Linux package node you are configuring then you can skip this step.

  2. Reconfigure GitLab for the changes to take effect.

Advanced configuration options are supported and can be added if needed.

PostgreSQL post-configuration

SSH in to any of the Patroni nodes on the primary site:

  1. Check the status of the leader and cluster:

    gitlab-ctl patroni members

    The output should be similar to the following:

    | Cluster       | Member                            |  Host     | Role   | State   | TL  | Lag in MB | Pending restart |
|---------------|-----------------------------------|-----------|--------|---------|-----|-----------|-----------------|
| postgresql-ha | <PostgreSQL primary hostname>     | 10.6.0.21 | Leader | running | 175 |           | *               |
| postgresql-ha | <PostgreSQL secondary 1 hostname> | 10.6.0.22 |        | running | 175 | 0         | *               |
| postgresql-ha | <PostgreSQL secondary 2 hostname> | 10.6.0.23 |        | running | 175 | 0         | *               |

If the 'State' column for any node doesn't say "running", check the PostgreSQL replication and failover troubleshooting section before proceeding.

Configure PgBouncer

Now that the PostgreSQL servers are all set up, let's configure PgBouncer for tracking and handling reads/writes to the primary database.

NOTE: PgBouncer is single threaded and doesn't significantly benefit from an increase in CPU cores. Refer to the scaling documentation for more information.

The following IPs will be used as an example:

  • 10.6.0.31: PgBouncer 1
  • 10.6.0.32: PgBouncer 2
  • 10.6.0.33: PgBouncer 3

  1. On each PgBouncer node, edit /etc/gitlab/gitlab.rb, and replace <consul_password_hash> and <pgbouncer_password_hash> with the password hashes you set up previously:

    # Disable all components except Pgbouncer and Consul agent
roles(['pgbouncer_role'])

# Configure PgBouncer
pgbouncer['admin_users'] = %w(pgbouncer gitlab-consul)
pgbouncer['users'] = {
   'gitlab-consul': {
      password: '<consul_password_hash>'
   },
   'pgbouncer': {
      password: '<pgbouncer_password_hash>'
   }
}

# Configure Consul agent
consul['watchers'] = %w(postgresql)
consul['configuration'] = {
retry_join: %w(10.6.0.11 10.6.0.12 10.6.0.13)
}

# Enable service discovery for Prometheus
consul['monitoring_service_discovery'] = true

# Set the network addresses that the exporters will listen on
node_exporter['listen_address'] = '0.0.0.0:9100'
pgbouncer_exporter['listen_address'] = '0.0.0.0:9188'

  2. Copy the /etc/gitlab/gitlab-secrets.json file from the first Linux package node you configured and add or replace the file of the same name on this server. If this is the first Linux package node you are configuring then you can skip this step.

  3. Reconfigure GitLab for the changes to take effect.

  4. Create a .pgpass file so Consul is able to reload PgBouncer. Enter the PgBouncer password twice when asked:

    gitlab-ctl write-pgpass --host 127.0.0.1 --database pgbouncer --user pgbouncer --hostuser gitlab-consul

  5. Ensure each node is talking to the current master:

    gitlab-ctl pgb-console # You will be prompted for PGBOUNCER_PASSWORD

    If there is an error psql: ERROR: Auth failed after typing in the password, ensure you previously generated the MD5 password hashes with the correct format. The correct format is to concatenate the password and the username: PASSWORDUSERNAME. For example, Sup3rS3cr3tpgbouncer would be the text needed to generate an MD5 password hash for the pgbouncer user.

  6. Once the console prompt is available, run the following queries:

    show databases ; show clients ;

    The output should be similar to the following:

            name         |  host       | port |      database       | force_user | pool_size | reserve_pool | pool_mode | max_connections | current_connections
---------------------+-------------+------+---------------------+------------+-----------+--------------+-----------+-----------------+---------------------
 gitlabhq_production | MASTER_HOST | 5432 | gitlabhq_production |            |        20 |            0 |           |               0 |                   0
 pgbouncer           |             | 6432 | pgbouncer           | pgbouncer  |         2 |            0 | statement |               0 |                   0
(2 rows)

 type |   user    |      database       |  state  |   addr         | port  | local_addr | local_port |    connect_time     |    request_time     |    ptr    | link | remote_pid | tls
------+-----------+---------------------+---------+----------------+-------+------------+------------+---------------------+---------------------+-----------+------+------------+-----
 C    | pgbouncer | pgbouncer           | active  | 127.0.0.1      | 56846 | 127.0.0.1  |       6432 | 2017-08-21 18:09:59 | 2017-08-21 18:10:48 | 0x22b3880 |      |          0 |
(2 rows)

  7. Verify the GitLab services are running:

    sudo gitlab-ctl status

    The output should be similar to the following:

    run: consul: (pid 31530) 77150s; run: log: (pid 31106) 77182s
run: logrotate: (pid 32613) 3357s; run: log: (pid 30107) 77500s
run: node-exporter: (pid 31550) 77149s; run: log: (pid 30138) 77493s
run: pgbouncer: (pid 32033) 75593s; run: log: (pid 31117) 77175s
run: pgbouncer-exporter: (pid 31558) 77148s; run: log: (pid 31498) 77156s

Configure Gitaly Cluster

Gitaly Cluster is a GitLab-provided and recommended fault tolerant solution for storing Git repositories. In this configuration, every Git repository is stored on every Gitaly node in the cluster, with one being designated the primary, and failover occurs automatically if the primary node goes down.

WARNING: Gitaly specifications are based on high percentiles of both usage patterns and repository sizes in good health. However, if you have large monorepos (larger than several gigabytes) or additional workloads these can significantly impact the performance of the environment and further adjustments may be required. If this applies to you, we strongly recommended referring to the linked documentation as well as reaching out to your Customer Success Manager or our Support team for further guidance.

Gitaly Cluster provides the benefits of fault tolerance, but comes with additional complexity of setup and management. Review the existing technical limitations and considerations before deploying Gitaly Cluster.

For guidance on:

The recommended cluster setup includes the following components:

  • 3 Gitaly nodes: Replicated storage of Git repositories.
  • 3 Praefect nodes: Router and transaction manager for Gitaly Cluster.
  • 1 Praefect PostgreSQL node: Database server for Praefect. A third-party solution is required for Praefect database connections to be made highly available.
  • 1 load balancer: A load balancer is required for Praefect. The internal load balancer is used.

This section details how to configure the recommended standard setup in order. For more advanced setups refer to the standalone Gitaly Cluster documentation.

Configure Praefect PostgreSQL

Praefect, the routing and transaction manager for Gitaly Cluster, requires its own database server to store data on Gitaly Cluster status.

If you want to have a highly available setup, Praefect requires a third-party PostgreSQL database. A built-in solution is being worked on.

Praefect non-HA PostgreSQL standalone using the Linux package

The following IPs will be used as an example:

  • 10.6.0.141: Praefect PostgreSQL

First, make sure to install the Linux GitLab package in the Praefect PostgreSQL node. Following the steps, install the necessary dependencies from step 1, and add the GitLab package repository from step 2. When installing GitLab in the second step, do not supply the EXTERNAL_URL value.

  1. SSH in to the Praefect PostgreSQL node.

  2. Create a strong password to be used for the Praefect PostgreSQL user. Take note of this password as <praefect_postgresql_password>.

  3. Generate the password hash for the Praefect PostgreSQL username/password pair. This assumes you will use the default username of praefect (recommended). The command will request the password <praefect_postgresql_password> and confirmation. Use the value that is output by this command in the next step as the value of <praefect_postgresql_password_hash>:

    sudo gitlab-ctl pg-password-md5 praefect

  4. Edit /etc/gitlab/gitlab.rb replacing values noted in the # START user configuration section:

    # Disable all components except PostgreSQL and Consul
roles(['postgres_role', 'consul_role'])

# PostgreSQL configuration
postgresql['listen_address'] = '0.0.0.0'

# Prevent database migrations from running on upgrade automatically
gitlab_rails['auto_migrate'] = false

# Configure the Consul agent
## Enable service discovery for Prometheus
consul['monitoring_service_discovery'] =  true

# START user configuration
# Please set the real values as explained in Required Information section
#
# Replace PRAEFECT_POSTGRESQL_PASSWORD_HASH with a generated md5 value
postgresql['sql_user_password'] = "<praefect_postgresql_password_hash>"

# Replace XXX.XXX.XXX.XXX/YY with Network Address
postgresql['trust_auth_cidr_addresses'] = %w(10.6.0.0/24 127.0.0.1/32)

# Set the network addresses that the exporters will listen on for monitoring
node_exporter['listen_address'] = '0.0.0.0:9100'
postgres_exporter['listen_address'] = '0.0.0.0:9187'

## The IPs of the Consul server nodes
## You can also use FQDNs and intermix them with IPs
consul['configuration'] = {
   retry_join: %w(10.6.0.11 10.6.0.12 10.6.0.13),
}
#
# END user configuration

  5. Copy the /etc/gitlab/gitlab-secrets.json file from the first Linux package node you configured and add or replace the file of the same name on this server. If this is the first Linux package node you are configuring then you can skip this step.

  6. Reconfigure GitLab for the changes to take effect.

  7. Follow the post configuration.

Praefect HA PostgreSQL third-party solution

As noted, a third-party PostgreSQL solution for Praefect's database is recommended if aiming for full High Availability.

There are many third-party solutions for PostgreSQL HA. The solution selected must have the following to work with Praefect:

  • A static IP for all connections that doesn't change on failover.
  • LISTEN SQL functionality must be supported.

NOTE: With a third-party setup, it's possible to colocate Praefect's database on the same server as the main GitLab database as a convenience unless you are using Geo, where separate database instances are required for handling replication correctly. In this setup, the specs of the main database setup shouldn't need to be changed as the impact should be minimal.

A reputable provider or solution should be used for this. Google Cloud SQL and Amazon RDS are known to work. However, Amazon Aurora is incompatible with load balancing enabled by default in 14.4.0. See Recommended cloud providers and services for more information.

Once the database is set up, follow the post configuration.

Praefect PostgreSQL post-configuration

After the Praefect PostgreSQL server has been set up, you'll then need to configure the user and database for Praefect to use.

We recommend the user be named praefect and the database praefect_production, and these can be configured as standard in PostgreSQL. The password for the user is the same as the one you configured earlier as <praefect_postgresql_password>.

This is how this would work with a Linux package PostgreSQL setup:

  1. SSH in to the Praefect PostgreSQL node.

  2. Connect to the PostgreSQL server with administrative access. The gitlab-psql user should be used here for this as it's added by default in the Linux package. The database template1 is used because it is created by default on all PostgreSQL servers.

    /opt/gitlab/embedded/bin/psql -U gitlab-psql -d template1 -h POSTGRESQL_SERVER_ADDRESS

  3. Create the new user praefect, replacing <praefect_postgresql_password>:

    CREATE ROLE praefect WITH LOGIN CREATEDB PASSWORD '<praefect_postgresql_password>';

  4. Reconnect to the PostgreSQL server, this time as the praefect user:

    /opt/gitlab/embedded/bin/psql -U praefect -d template1 -h POSTGRESQL_SERVER_ADDRESS

  5. Create a new database praefect_production:

    CREATE DATABASE praefect_production WITH ENCODING=UTF8;

Configure Praefect

Praefect is the router and transaction manager for Gitaly Cluster and all connections to Gitaly go through it. This section details how to configure it.

NOTE: Praefect must be deployed in an odd number of 3 nodes or more. This is to ensure the nodes can take votes as part of a quorum.

Praefect requires several secret tokens to secure communications across the Cluster:

  • <praefect_external_token>: Used for repositories hosted on your Gitaly cluster and can only be accessed by Gitaly clients that carry this token.
  • <praefect_internal_token>: Used for replication traffic inside your Gitaly cluster. This is distinct from praefect_external_token because Gitaly clients must not be able to access internal nodes of the Praefect cluster directly; that could lead to data loss.
  • <praefect_postgresql_password>: The Praefect PostgreSQL password defined in the previous section is also required as part of this setup.

Gitaly Cluster nodes are configured in Praefect via a virtual storage. Each storage contains the details of each Gitaly node that makes up the cluster. Each storage is also given a name and this name is used in several areas of the configuration. In this guide, the name of the storage will be default. Also, this guide is geared towards new installs, if upgrading an existing environment to use Gitaly Cluster, you may need to use a different name. Refer to the Praefect documentation for more information.

The following IPs will be used as an example:

  • 10.6.0.131: Praefect 1
  • 10.6.0.132: Praefect 2
  • 10.6.0.133: Praefect 3

To configure the Praefect nodes, on each one:

  1. SSH in to the Praefect server.

  2. Download and install the Linux package of your choice. Be sure to follow only installation steps 1 and 2 on the page.

  3. Edit the /etc/gitlab/gitlab.rb file to configure Praefect:

    NOTE: You can't remove the default entry from virtual_storages because GitLab requires it.

    # Avoid running unnecessary services on the Praefect server
gitaly['enable'] = false
postgresql['enable'] = false
redis['enable'] = false
nginx['enable'] = false
puma['enable'] = false
sidekiq['enable'] = false
gitlab_workhorse['enable'] = false
prometheus['enable'] = false
alertmanager['enable'] = false
gitlab_exporter['enable'] = false
gitlab_kas['enable'] = false

# Praefect Configuration
praefect['enable'] = true

# Prevent database migrations from running on upgrade automatically
praefect['auto_migrate'] = false
gitlab_rails['auto_migrate'] = false

# Configure the Consul agent
consul['enable'] = true
## Enable service discovery for Prometheus
consul['monitoring_service_discovery'] = true

# START user configuration
# Please set the real values as explained in Required Information section
#

praefect['configuration'] = {
   # ...
   listen_addr: '0.0.0.0:2305',
   auth: {
     # ...
     #
     # Praefect External Token
     # This is needed by clients outside the cluster (like GitLab Shell) to communicate with the Praefect cluster
     token: '<praefect_external_token>',
   },
   # Praefect Database Settings
   database: {
     # ...
     host: '10.6.0.141',
     port: 5432,
     # `no_proxy` settings must always be a direct connection for caching
     session_pooled: {
        # ...
        host: '10.6.0.141',
        port: 5432,
        dbname: 'praefect_production',
        user: 'praefect',
        password: '<praefect_postgresql_password>',
     },
   },
   # Praefect Virtual Storage config
   # Name of storage hash must match storage name in git_data_dirs on GitLab
   # server ('praefect') and in gitaly['configuration'][:storage] on Gitaly nodes ('gitaly-1')
   virtual_storage: [
      {
         # ...
         name: 'default',
         node: [
            {
               storage: 'gitaly-1',
               address: 'tcp://10.6.0.91:8075',
               token: '<praefect_internal_token>'
            },
            {
               storage: 'gitaly-2',
               address: 'tcp://10.6.0.92:8075',
               token: '<praefect_internal_token>'
            },
            {
               storage: 'gitaly-3',
               address: 'tcp://10.6.0.93:8075',
               token: '<praefect_internal_token>'
            },
         ],
      },
   ],
   # Set the network address Praefect will listen on for monitoring
   prometheus_listen_addr: '0.0.0.0:9652',
}

# Set the network address the node exporter will listen on for monitoring
node_exporter['listen_address'] = '0.0.0.0:9100'

## The IPs of the Consul server nodes
## You can also use FQDNs and intermix them with IPs
consul['configuration'] = {
   retry_join: %w(10.6.0.11 10.6.0.12 10.6.0.13),
}
#
# END user configuration

  4. Copy the /etc/gitlab/gitlab-secrets.json file from the first Linux package node you configured and add or replace the file of the same name on this server. If this is the first Linux package node you are configuring then you can skip this step.

  5. Praefect requires to run some database migrations, much like the main GitLab application. For this you should select one Praefect node only to run the migrations, AKA the Deploy Node. This node must be configured first before the others as follows:

    1. In the /etc/gitlab/gitlab.rb file, change the praefect['auto_migrate'] setting value from false to true

    2. To ensure database migrations are only run during reconfigure and not automatically on upgrade, run:

    sudo touch /etc/gitlab/skip-auto-reconfigure
    1. Reconfigure GitLab for the changes to take effect and to run the Praefect database migrations.

  6. On all other Praefect nodes, reconfigure GitLab for the changes to take effect.

Configure Gitaly

The Gitaly server nodes that make up the cluster have requirements that are dependent on data and load.

WARNING: Gitaly specifications are based on high percentiles of both usage patterns and repository sizes in good health. However, if you have large monorepos (larger than several gigabytes) or additional workloads these can significantly impact the performance of the environment and further adjustments may be required. If this applies to you, we strongly recommended referring to the linked documentation as well as reaching out to your Customer Success Manager or our Support team for further guidance.

Due to Gitaly having notable input and output requirements, we strongly recommend that all Gitaly nodes use solid-state drives (SSDs). These SSDs should have a throughput of at least 8,000 input/output operations per second (IOPS) for read operations and 2,000 IOPS for write operations. If you're running the environment on a Cloud provider, refer to their documentation about how to configure IOPS correctly.

Gitaly servers must not be exposed to the public internet, as Gitaly's network traffic is unencrypted by default. The use of a firewall is highly recommended to restrict access to the Gitaly server. Another option is to use TLS.

For configuring Gitaly you should note the following:

  • gitaly['configuration'][:storage] should be configured to reflect the storage path for the specific Gitaly node
  • auth_token should be the same as praefect_internal_token

The following IPs will be used as an example:

  • 10.6.0.91: Gitaly 1
  • 10.6.0.92: Gitaly 2
  • 10.6.0.93: Gitaly 3

On each node:

  1. Download and install the Linux package package of your choice. Be sure to follow only installation steps 1 and 2 on the page, and do not provide the EXTERNAL_URL value.

  2. Edit the Gitaly server node's /etc/gitlab/gitlab.rb file to configure storage paths, enable the network listener, and to configure the token:

    # Avoid running unnecessary services on the Gitaly server
postgresql['enable'] = false
redis['enable'] = false
nginx['enable'] = false
puma['enable'] = false
sidekiq['enable'] = false
gitlab_workhorse['enable'] = false
prometheus['enable'] = false
alertmanager['enable'] = false
gitlab_exporter['enable'] = false
gitlab_kas['enable'] = false

# Prevent database migrations from running on upgrade automatically
gitlab_rails['auto_migrate'] = false

# Gitaly
gitaly['enable'] = true

# Configure the gitlab-shell API callback URL. Without this, `git push` will
# fail. This can be your 'front door' GitLab URL or an internal load
# balancer.
gitlab_rails['internal_api_url'] = 'https://gitlab.example.com'

# Configure the Consul agent
consul['enable'] = true
## Enable service discovery for Prometheus
consul['monitoring_service_discovery'] = true

# START user configuration
# Please set the real values as explained in Required Information section
#
## The IPs of the Consul server nodes
## You can also use FQDNs and intermix them with IPs
consul['configuration'] = {
   retry_join: %w(10.6.0.11 10.6.0.12 10.6.0.13),
}

# Set the network address that the node exporter will listen on for monitoring
node_exporter['listen_address'] = '0.0.0.0:9100'

gitaly['configuration'] = {
   # ...
   #
   # Make Gitaly accept connections on all network interfaces. You must use
   # firewalls to restrict access to this address/port.
   # Comment out following line if you only want to support TLS connections
   listen_addr: '0.0.0.0:8075',
   # Set the network address that Gitaly will listen on for monitoring
   prometheus_listen_addr: '0.0.0.0:9236',
   # Gitaly Auth Token
   # Should be the same as praefect_internal_token
   auth: {
      # ...
      token: '<praefect_internal_token>',
   },
   # Gitaly Pack-objects cache
   # Recommended to be enabled for improved performance but can notably increase disk I/O
   # Refer to https://docs.gitlab.com/ee/administration/gitaly/configure_gitaly.html#pack-objects-cache for more info
   pack_objects_cache: {
      # ...
      enabled: true,
   },
}

#
# END user configuration

  3. Append the following to /etc/gitlab/gitlab.rb for each respective server:

    • On Gitaly node 1:

      gitaly['configuration'] = {
   # ...
   storage: [
      {
         name: 'gitaly-1',
         path: '/var/opt/gitlab/git-data',
      },
   ],
}

    • On Gitaly node 2:

      gitaly['configuration'] = {
   # ...
   storage: [
      {
         name: 'gitaly-2',
         path: '/var/opt/gitlab/git-data',
      },
   ],
}

    • On Gitaly node 3:

      gitaly['configuration'] = {
   # ...
   storage: [
      {
         name: 'gitaly-3',
         path: '/var/opt/gitlab/git-data',
      },
   ],
}

  4. Copy the /etc/gitlab/gitlab-secrets.json file from the first Linux package node you configured and add or replace the file of the same name on this server. If this is the first Linux package node you are configuring then you can skip this step.

  5. Save the file, and then reconfigure GitLab.

Gitaly Cluster TLS support

Praefect supports TLS encryption. To communicate with a Praefect instance that listens for secure connections, you must:

  • Use a tls:// URL scheme in the gitaly_address of the corresponding storage entry in the GitLab configuration.
  • Bring your own certificates because this isn't provided automatically. The certificate corresponding to each Praefect server must be installed on that Praefect server.

Additionally the certificate, or its certificate authority, must be installed on all Gitaly servers and on all Praefect clients that communicate with it following the procedure described in GitLab custom certificate configuration (and repeated below).

Note the following:

  • The certificate must specify the address you use to access the Praefect server. You must add the hostname or IP address as a Subject Alternative Name to the certificate.
  • You can configure Praefect servers with both an unencrypted listening address listen_addr and an encrypted listening address tls_listen_addr at the same time. This allows you to do a gradual transition from unencrypted to encrypted traffic, if necessary. To disable the unencrypted listener, set praefect['configuration'][:listen_addr] = nil.
  • The Internal Load Balancer will also access to the certificates and need to be configured to allow for TLS passthrough. Refer to the load balancers documentation on how to configure this.

To configure Praefect with TLS:

  1. Create certificates for Praefect servers.

  2. On the Praefect servers, create the /etc/gitlab/ssl directory and copy your key and certificate there:

    sudo mkdir -p /etc/gitlab/ssl
sudo chmod 755 /etc/gitlab/ssl
sudo cp key.pem cert.pem /etc/gitlab/ssl/
sudo chmod 644 key.pem cert.pem

  3. Edit /etc/gitlab/gitlab.rb and add:

    praefect['configuration'] = {
   # ...
   tls_listen_addr: '0.0.0.0:3305',
   tls: {
      # ...
      certificate_path: '/etc/gitlab/ssl/cert.pem',
      key_path: '/etc/gitlab/ssl/key.pem',
   },
}

  4. Save the file and reconfigure.

  5. On the Praefect clients (including each Gitaly server), copy the certificates, or their certificate authority, into /etc/gitlab/trusted-certs:

    sudo cp cert.pem /etc/gitlab/trusted-certs/

  6. On the Praefect clients (except Gitaly servers), edit git_data_dirs in /etc/gitlab/gitlab.rb as follows:

    git_data_dirs({
  "default" => {
    "gitaly_address" => 'tls://LOAD_BALANCER_SERVER_ADDRESS:3305',
    "gitaly_token" => 'PRAEFECT_EXTERNAL_TOKEN'
  }
})

  7. Save the file and reconfigure GitLab.

Configure Sidekiq

Sidekiq requires connection to the Redis, PostgreSQL and Gitaly instances. It also requires a connection to Object Storage as recommended.

NOTE: Because it's recommended to use Object storage instead of NFS for data objects, the following examples include the Object storage configuration.

NOTE: If you find that the environment's Sidekiq job processing is slow with long queues you can scale it accordingly. Refer to the scaling documentation for more information.

The following IPs will be used as an example:

  • 10.6.0.71: Sidekiq 1
  • 10.6.0.72: Sidekiq 2

To configure the Sidekiq nodes, on each one:

  1. SSH in to the Sidekiq server.

  2. Download and install the Linux package of your choice. Be sure to follow only installation steps 1 and 2 on the page.

  3. Create or edit /etc/gitlab/gitlab.rb and use the following configuration:

    # https://docs.gitlab.com/omnibus/roles/#sidekiq-roles
roles(["sidekiq_role"])

# External URL
## This should match the URL of the external load balancer
external_url 'https://gitlab.example.com'

# Redis
redis['master_name'] = 'gitlab-redis'

## The same password for Redis authentication you set up for the master node.
redis['master_password'] = '<redis_primary_password>'

## A list of sentinels with `host` and `port`
gitlab_rails['redis_sentinels'] = [
   {'host' => '10.6.0.11', 'port' => 26379},
   {'host' => '10.6.0.12', 'port' => 26379},
   {'host' => '10.6.0.13', 'port' => 26379},
]

# Gitaly Cluster
## git_data_dirs get configured for the Praefect virtual storage
## Address is Internal Load Balancer for Praefect
## Token is praefect_external_token
git_data_dirs({
  "default" => {
    "gitaly_address" => "tcp://10.6.0.40:2305", # internal load balancer IP
    "gitaly_token" => '<praefect_external_token>'
  }
})

# PostgreSQL
gitlab_rails['db_host'] = '10.6.0.40' # internal load balancer IP
gitlab_rails['db_port'] = 6432
gitlab_rails['db_password'] = '<postgresql_user_password>'
gitlab_rails['db_load_balancing'] = { 'hosts' => ['10.6.0.21', '10.6.0.22', '10.6.0.23'] } # PostgreSQL IPs

## Prevent database migrations from running on upgrade automatically
gitlab_rails['auto_migrate'] = false

# Sidekiq
sidekiq['enable'] = true
sidekiq['listen_address'] = "0.0.0.0"

## Set number of Sidekiq queue processes to the same number as available CPUs
sidekiq['queue_groups'] = ['*'] * 4

# Monitoring
consul['enable'] = true
consul['monitoring_service_discovery'] =  true

consul['configuration'] = {
   retry_join: %w(10.6.0.11 10.6.0.12 10.6.0.13)
}

## Set the network addresses that the exporters will listen on
node_exporter['listen_address'] = '0.0.0.0:9100'

## Add the monitoring node's IP address to the monitoring whitelist
gitlab_rails['monitoring_whitelist'] = ['10.6.0.81/32', '127.0.0.0/8']
gitlab_rails['prometheus_address'] = '10.6.0.81:9090'

# Object Storage
## This is an example for configuring Object Storage on GCP
## Replace this config with your chosen Object Storage provider as desired
gitlab_rails['object_store']['enabled'] = true
gitlab_rails['object_store']['connection'] = {
  'provider' => 'Google',
  'google_project' => '<gcp-project-name>',
  'google_json_key_location' => '<path-to-gcp-service-account-key>'
}
gitlab_rails['object_store']['objects']['artifacts']['bucket'] = "<gcp-artifacts-bucket-name>"
gitlab_rails['object_store']['objects']['external_diffs']['bucket'] = "<gcp-external-diffs-bucket-name>"
gitlab_rails['object_store']['objects']['lfs']['bucket'] = "<gcp-lfs-bucket-name>"
gitlab_rails['object_store']['objects']['uploads']['bucket'] = "<gcp-uploads-bucket-name>"
gitlab_rails['object_store']['objects']['packages']['bucket'] = "<gcp-packages-bucket-name>"
gitlab_rails['object_store']['objects']['dependency_proxy']['bucket'] = "<gcp-dependency-proxy-bucket-name>"
gitlab_rails['object_store']['objects']['terraform_state']['bucket'] = "<gcp-terraform-state-bucket-name>"

gitlab_rails['backup_upload_connection'] = {
  'provider' => 'Google',
  'google_project' => '<gcp-project-name>',
  'google_json_key_location' => '<path-to-gcp-service-account-key>'
}
gitlab_rails['backup_upload_remote_directory'] = "<gcp-backups-state-bucket-name>"

gitlab_rails['ci_secure_files_object_store_enabled'] = true
gitlab_rails['ci_secure_files_object_store_remote_directory'] = "gcp-ci_secure_files-bucket-name"

gitlab_rails['ci_secure_files_object_store_connection'] = {
   'provider' => 'Google',
   'google_project' => '<gcp-project-name>',
   'google_json_key_location' => '<path-to-gcp-service-account-key>'
}

  4. Copy the /etc/gitlab/gitlab-secrets.json file from the first Linux package node you configured and add or replace the file of the same name on this server. If this is the first Linux package node you are configuring then you can skip this step.

  5. To ensure database migrations are only run during reconfigure and not automatically on upgrade, run:

    sudo touch /etc/gitlab/skip-auto-reconfigure

    Only a single designated node should handle migrations as detailed in the GitLab Rails post-configuration section.

  6. Save the file and reconfigure GitLab.

  7. Verify the GitLab services are running:

    sudo gitlab-ctl status

    The output should be similar to the following:

    run: consul: (pid 30114) 77353s; run: log: (pid 29756) 77367s
run: logrotate: (pid 9898) 3561s; run: log: (pid 29653) 77380s
run: node-exporter: (pid 30134) 77353s; run: log: (pid 29706) 77372s
run: sidekiq: (pid 30142) 77351s; run: log: (pid 29638) 77386s

Configure GitLab Rails

This section describes how to configure the GitLab application (Rails) component.

Rails requires connections to the Redis, PostgreSQL and Gitaly instances. It also requires a connection to Object Storage as recommended.

NOTE: Because it's recommended to use Object storage instead of NFS for data objects, the following examples include the Object storage configuration.

On each node perform the following:

  1. Download and install the Linux package of your choice. Be sure to follow only installation steps 1 and 2 on the page.

  2. Create or edit /etc/gitlab/gitlab.rb and use the following configuration. To maintain uniformity of links across nodes, the external_url on the application server should point to the external URL that users will use to access GitLab. This would be the URL of the external load balancer which will route traffic to the GitLab application server:

    external_url 'https://gitlab.example.com'

# git_data_dirs get configured for the Praefect virtual storage
# Address is Internal Load Balancer for Praefect
# Token is praefect_external_token
git_data_dirs({
  "default" => {
    "gitaly_address" => "tcp://10.6.0.40:2305", # internal load balancer IP
    "gitaly_token" => '<praefect_external_token>'
  }
})

## Disable components that will not be on the GitLab application server
roles(['application_role'])
gitaly['enable'] = false
nginx['enable'] = true
sidekiq['enable'] = false

## PostgreSQL connection details
# Disable PostgreSQL on the application node
postgresql['enable'] = false
gitlab_rails['db_host'] = '10.6.0.20' # internal load balancer IP
gitlab_rails['db_port'] = 6432
gitlab_rails['db_password'] = '<postgresql_user_password>'
gitlab_rails['db_load_balancing'] = { 'hosts' => ['10.6.0.21', '10.6.0.22', '10.6.0.23'] } # PostgreSQL IPs

# Prevent database migrations from running on upgrade automatically
gitlab_rails['auto_migrate'] = false

## Redis connection details
## Must be the same in every sentinel node
redis['master_name'] = 'gitlab-redis'

## The same password for Redis authentication you set up for the Redis primary node.
redis['master_password'] = '<redis_primary_password>'

## A list of sentinels with `host` and `port`
gitlab_rails['redis_sentinels'] = [
  {'host' => '10.6.0.11', 'port' => 26379},
  {'host' => '10.6.0.12', 'port' => 26379},
  {'host' => '10.6.0.13', 'port' => 26379}
]

## Enable service discovery for Prometheus
consul['enable'] = true
consul['monitoring_service_discovery'] =  true

# Set the network addresses that the exporters used for monitoring will listen on
node_exporter['listen_address'] = '0.0.0.0:9100'
gitlab_workhorse['prometheus_listen_addr'] = '0.0.0.0:9229'
sidekiq['listen_address'] = "0.0.0.0"
puma['listen'] = '0.0.0.0'

## The IPs of the Consul server nodes
## You can also use FQDNs and intermix them with IPs
consul['configuration'] = {
   retry_join: %w(10.6.0.11 10.6.0.12 10.6.0.13),
}

# Add the monitoring node's IP address to the monitoring whitelist and allow it to
# scrape the NGINX metrics
gitlab_rails['monitoring_whitelist'] = ['10.6.0.81/32', '127.0.0.0/8']
nginx['status']['options']['allow'] = ['10.6.0.81/32', '127.0.0.0/8']
gitlab_rails['prometheus_address'] = '10.6.0.81:9090'

## Uncomment and edit the following options if you have set up NFS
##
## Prevent GitLab from starting if NFS data mounts are not available
##
#high_availability['mountpoint'] = '/var/opt/gitlab/git-data'
##
## Ensure UIDs and GIDs match between servers for permissions via NFS
##
#user['uid'] = 9000
#user['gid'] = 9000
#web_server['uid'] = 9001
#web_server['gid'] = 9001
#registry['uid'] = 9002
#registry['gid'] = 9002

# Object storage
# This is an example for configuring Object Storage on GCP
# Replace this config with your chosen Object Storage provider as desired
gitlab_rails['object_store']['enabled'] = true
gitlab_rails['object_store']['connection'] = {
  'provider' => 'Google',
  'google_project' => '<gcp-project-name>',
  'google_json_key_location' => '<path-to-gcp-service-account-key>'
}
gitlab_rails['object_store']['objects']['artifacts']['bucket'] = "<gcp-artifacts-bucket-name>"
gitlab_rails['object_store']['objects']['external_diffs']['bucket'] = "<gcp-external-diffs-bucket-name>"
gitlab_rails['object_store']['objects']['lfs']['bucket'] = "<gcp-lfs-bucket-name>"
gitlab_rails['object_store']['objects']['uploads']['bucket'] = "<gcp-uploads-bucket-name>"
gitlab_rails['object_store']['objects']['packages']['bucket'] = "<gcp-packages-bucket-name>"
gitlab_rails['object_store']['objects']['dependency_proxy']['bucket'] = "<gcp-dependency-proxy-bucket-name>"
gitlab_rails['object_store']['objects']['terraform_state']['bucket'] = "<gcp-terraform-state-bucket-name>"

gitlab_rails['backup_upload_connection'] = {
  'provider' => 'Google',
  'google_project' => '<gcp-project-name>',
  'google_json_key_location' => '<path-to-gcp-service-account-key>'
}
gitlab_rails['backup_upload_remote_directory'] = "<gcp-backups-state-bucket-name>"
gitlab_rails['ci_secure_files_object_store_enabled'] = true
gitlab_rails['ci_secure_files_object_store_remote_directory'] = "gcp-ci_secure_files-bucket-name"

gitlab_rails['ci_secure_files_object_store_connection'] = {
   'provider' => 'Google',
   'google_project' => '<gcp-project-name>',
   'google_json_key_location' => '<path-to-gcp-service-account-key>'
}

  3. If you're using Gitaly with TLS support, make sure the git_data_dirs entry is configured with tls instead of tcp:

    git_data_dirs({
  "default" => {
    "gitaly_address" => "tls://10.6.0.40:2305", # internal load balancer IP
    "gitaly_token" => '<praefect_external_token>'
  }
})

    1. Copy the cert into /etc/gitlab/trusted-certs:

      sudo cp cert.pem /etc/gitlab/trusted-certs/

  4. Copy the /etc/gitlab/gitlab-secrets.json file from the first Linux package node you configured and add or replace the file of the same name on this server. If this is the first Linux package node you are configuring then you can skip this step.

  5. Copy the SSH host keys (all in the name format /etc/ssh/ssh_host_*_key*) from the first Linux package node you configured and add or replace the files of the same name on this server. This ensures host mismatch errors aren't thrown for your users as they hit the load balanced Rails nodes. If this is the first Linux package node you are configuring, then you can skip this step.

  6. To ensure database migrations are only run during reconfigure and not automatically on upgrade, run:

    sudo touch /etc/gitlab/skip-auto-reconfigure

    Only a single designated node should handle migrations as detailed in the GitLab Rails post-configuration section.

  7. Reconfigure GitLab for the changes to take effect.

  8. Enable incremental logging.

  9. Run sudo gitlab-rake gitlab:gitaly:check to confirm the node can connect to Gitaly.

  10. Tail the logs to see the requests:

    sudo gitlab-ctl tail gitaly

  11. Verify the GitLab services are running:

    sudo gitlab-ctl status

    The output should be similar to the following:

    run: consul: (pid 4890) 8647s; run: log: (pid 29962) 79128s
run: gitlab-exporter: (pid 4902) 8647s; run: log: (pid 29913) 79134s
run: gitlab-workhorse: (pid 4904) 8646s; run: log: (pid 29713) 79155s
run: logrotate: (pid 12425) 1446s; run: log: (pid 29798) 79146s
run: nginx: (pid 4925) 8646s; run: log: (pid 29726) 79152s
run: node-exporter: (pid 4931) 8645s; run: log: (pid 29855) 79140s
run: puma: (pid 4936) 8645s; run: log: (pid 29656) 79161s

When you specify https in the external_url, as in the previous example, GitLab expects that the SSL certificates are in /etc/gitlab/ssl/. If the certificates aren't present, NGINX will fail to start. For more information, see the HTTPS documentation.

GitLab Rails post-configuration

  1. Ensure that all migrations ran:

    gitlab-rake gitlab:db:configure

    Note that this requires the Rails node to be configured to connect to the primary database directly, bypassing PgBouncer. After migrations have completed, you must configure the node to pass through PgBouncer again.

  2. Configure fast lookup of authorized SSH keys in the database.

Configure Prometheus

The Linux package can be used to configure a standalone Monitoring node running Prometheus:

  1. SSH in to the Monitoring node.

  2. Download and install the Linux package of your choice. Be sure to follow only installation steps 1 and 2 on the page.

  3. Edit /etc/gitlab/gitlab.rb and add the contents:

    roles(['monitoring_role', 'consul_role'])

external_url 'http://gitlab.example.com'

# Prometheus
prometheus['listen_address'] = '0.0.0.0:9090'
prometheus['monitor_kubernetes'] = false

# Enable service discovery for Prometheus
consul['monitoring_service_discovery'] =  true
consul['configuration'] = {
   retry_join: %w(10.6.0.11 10.6.0.12 10.6.0.13)
}

# Configure Prometheus to scrape services not covered by discovery
prometheus['scrape_configs'] = [
   {
      'job_name': 'pgbouncer',
      'static_configs' => [
         'targets' => [
         "10.6.0.31:9188",
         "10.6.0.32:9188",
         "10.6.0.33:9188",
         ],
      ],
   },
   {
      'job_name': 'praefect',
      'static_configs' => [
         'targets' => [
         "10.6.0.131:9652",
         "10.6.0.132:9652",
         "10.6.0.133:9652",
         ],
      ],
   },
]

nginx['enable'] = false

  4. Save the file and reconfigure GitLab.

  5. Verify the GitLab services are running:

    sudo gitlab-ctl status

    The output should be similar to the following:

    run: consul: (pid 31637) 17337s; run: log: (pid 29748) 78432s
run: logrotate: (pid 31809) 2936s; run: log: (pid 29581) 78462s
run: nginx: (pid 31665) 17335s; run: log: (pid 29556) 78468s
run: prometheus: (pid 31672) 17335s; run: log: (pid 29633) 78456s

Configure the object storage

GitLab supports using an object storage service for holding numerous types of data. It's recommended over NFS for data objects and in general it's better in larger setups as object storage is typically much more performant, reliable, and scalable. See Recommended cloud providers and services for more information.

There are two ways of specifying object storage configuration in GitLab:

The consolidated form is used in the following examples when available.

NOTE: When using the storage-specific form in GitLab 14.x and earlier, you should enable direct upload mode. The previous background upload mode, which was deprecated in 14.9, requires shared storage such as NFS.

Using separate buckets for each data type is the recommended approach for GitLab. This ensures there are no collisions across the various types of data GitLab stores. There are plans to enable the use of a single bucket in the future.

Enable incremental logging

GitLab Runner returns job logs in chunks which the Linux package caches temporarily on disk in /var/opt/gitlab/gitlab-ci/builds by default, even when using consolidated object storage. With default configuration, this directory needs to be shared through NFS on any GitLab Rails and Sidekiq nodes.

While sharing the job logs through NFS is supported, it's recommended to avoid the need to use NFS by enabling incremental logging (required when no NFS node has been deployed). Incremental logging uses Redis instead of disk space for temporary caching of job logs.

Configure advanced search

You can leverage Elasticsearch and enable advanced search for faster, more advanced code search across your entire GitLab instance.

Elasticsearch cluster design and requirements are dependent on your specific data. For recommended best practices about how to set up your Elasticsearch cluster alongside your instance, read how to choose the optimal cluster configuration.

Supported modifications for lower user counts (HA)

The 3,000 user GitLab reference architecture is the smallest we recommend that achieves High Availability (HA). However, for environments that need to serve fewer users but maintain HA, there are several supported modifications you can make to this architecture to reduce complexity and cost.

It should be noted that to achieve HA with GitLab, the 3,000 user architecture's makeup is ultimately what is required. Each component has various considerations and rules to follow, and the 3,000 user architecture meets all of these. Smaller versions of this architecture will be fundamentally the same, but with smaller performance requirements, several modifications can be considered as follows:

  • Lowering node specs: Depending on your user count, you can lower all suggested node specs as desired. However, it's recommended that you don't go lower than the general requirements.
  • Combining select nodes: Some nodes can be combined to reduce complexity at the cost of some performance:
    • GitLab Rails and Sidekiq: Sidekiq nodes can be removed and the component instead enabled on the GitLab Rails nodes.
    • PostgreSQL and PgBouncer: PgBouncer nodes could be removed and instead be enabled on PostgreSQL nodes with the Internal Load Balancer pointing to them. However, to enable Database Load Balancing, a separate PgBouncer array is still required.
  • Reducing the node counts: Some node types do not need consensus and can run with fewer nodes (but more than one for redundancy). This will also lead to reduced performance.
    • GitLab Rails and Sidekiq: Stateless services don't have a minimum node count. Two are enough for redundancy.
    • PostgreSQL and PgBouncer: A quorum is not strictly necessary. Two PostgreSQL nodes and two PgBouncer nodes are enough for redundancy.
  • Running select components in reputable Cloud PaaS solutions: Select components of the GitLab setup can instead be run on Cloud Provider PaaS solutions. By doing this, additional dependent components can also be removed:
    • PostgreSQL: Can be run on reputable Cloud PaaS solutions such as Google Cloud SQL or Amazon RDS. In this setup, the PgBouncer and Consul nodes are no longer required:
      • Consul may still be desired if Prometheus auto discovery is a requirement, otherwise you would need to manually add scrape configurations for all nodes.
        • As Redis Sentinel runs on the same box as Consul in this architecture, it may need to be run on a separate box if Redis is still being run using the Linux package.
    • Redis: Can be run on reputable Cloud PaaS solutions such as Google Memorystore and AWS ElastiCache. In this setup, the Redis Sentinel is no longer required.

Cloud Native Hybrid reference architecture with Helm Charts (alternative)

Run select components of cloud-native GitLab in Kubernetes with the GitLab Helm chart. In this setup, you can run the equivalent of GitLab Rails in the Kubernetes cluster called Webservice. You also can run the equivalent of Sidekiq nodes in the Kubernetes cluster called Sidekiq. In addition, the following other supporting services are supported: NGINX, Toolbox, Migrations, Prometheus.

Hybrid installations leverage the benefits of both cloud native and traditional compute deployments. With this, stateless components can benefit from cloud native workload management benefits while stateful components are deployed in compute VMs with Linux package installations to benefit from increased permanence.

Refer to the Helm charts Advanced configuration documentation for setup instructions including guidance on what GitLab secrets to sync between Kubernetes and the backend components.

NOTE: This is an advanced setup. Running services in Kubernetes is well known to be complex. This setup is only recommended if you have strong working knowledge and experience in Kubernetes. The rest of this section assumes this.

WARNING: Gitaly Cluster is not supported to be run in Kubernetes. Refer to epic 6127 for more details.

Cluster topology

The following tables and diagram detail the hybrid environment using the same formats as the typical environment above.

First are the components that run in Kubernetes. These run across several node groups, although you can change the overall makeup as desired as long as the minimum CPU and Memory requirements are observed.

Service Node Group Nodes Configuration GCP AWS Min Allocatable CPUs and Memory
Webservice 2 16 vCPU, 14.4 GB memory n1-highcpu-16 c5.4xlarge 31.8 vCPU, 24.8 GB memory
Sidekiq 3 4 vCPU, 15 GB memory n1-standard-4 m5.xlarge 11.8 vCPU, 38.9 GB memory
Supporting services 2 2 vCPU, 7.5 GB memory n1-standard-2 m5.large 3.9 vCPU, 11.8 GB memory
  • For this setup, we recommend and regularly test Google Kubernetes Engine (GKE) and Amazon Elastic Kubernetes Service (EKS). Other Kubernetes services may also work, but your mileage may vary.
  • Nodes configuration is shown as it is forced to ensure pod vCPU / memory ratios and avoid scaling during performance testing.
    • In production deployments, there is no need to assign pods to specific nodes. A minimum of three nodes per node group in three different availability zones is strongly recommended to align with resilient cloud architecture practices.

Next are the backend components that run on static compute VMs using the Linux package (or External PaaS services where applicable):

Service Nodes Configuration GCP AWS
Redis2 3 2 vCPU, 7.5 GB memory n1-standard-2 m5.large
Consul1 + Sentinel2 3 2 vCPU, 1.8 GB memory n1-highcpu-2 c5.large
PostgreSQL1 3 2 vCPU, 7.5 GB memory n1-standard-2 m5.large
PgBouncer1 3 2 vCPU, 1.8 GB memory n1-highcpu-2 c5.large
Internal load balancing node3 1 2 vCPU, 1.8 GB memory n1-highcpu-2 c5.large
Gitaly5 3 4 vCPU, 15 GB memory6 n1-standard-4 m5.xlarge
Praefect5 3 2 vCPU, 1.8 GB memory n1-highcpu-2 c5.large
Praefect PostgreSQL1 1+ 2 vCPU, 1.8 GB memory n1-highcpu-2 c5.large
Object storage4 - - - -
  1. Can be optionally run on reputable third-party external PaaS PostgreSQL solutions. See Provide your own PostgreSQL instance for more information.
  2. Can be optionally run on reputable third-party external PaaS Redis solutions. See Provide your own Redis instance for more information.
  3. Can be optionally run on reputable third-party load balancing services (LB PaaS). See Recommended cloud providers and services for more information.
  4. Should be run on reputable Cloud Provider or Self Managed solutions. See Configure the object storage for more information.
  5. Gitaly Cluster provides the benefits of fault tolerance, but comes with additional complexity of setup and management. Review the existing technical limitations and considerations before deploying Gitaly Cluster. If you want sharded Gitaly, use the same specs listed above for Gitaly.
  6. Gitaly specifications are based on high percentiles of both usage patterns and repository sizes in good health. However, if you have large monorepos (larger than several gigabytes) or additional workloads these can significantly impact Git and Gitaly performance and further adjustments will likely be required.

NOTE: For all PaaS solutions that involve configuring instances, it is strongly recommended to implement a minimum of three nodes in three different availability zones to align with resilient cloud architecture practices.

@startuml 3k
skinparam linetype ortho

card "Kubernetes via Helm Charts" as kubernetes {
  card "**External Load Balancer**" as elb #6a9be7

  together {
    collections "**Webservice** x2" as gitlab #32CD32
    collections "**Sidekiq** x3" as sidekiq #ff8dd1
  }

  card "**Supporting Services** x2" as support
}

card "**Internal Load Balancer**" as ilb #9370DB
collections "**Consul** x3" as consul #e76a9b

card "Gitaly Cluster" as gitaly_cluster {
  collections "**Praefect** x3" as praefect #FF8C00
  collections "**Gitaly** x3" as gitaly #FF8C00
  card "**Praefect PostgreSQL***\n//Non fault-tolerant//" as praefect_postgres #FF8C00

  praefect -[#FF8C00]-> gitaly
  praefect -[#FF8C00]> praefect_postgres
}

card "Database" as database {
  collections "**PGBouncer** x3" as pgbouncer #4EA7FF
  card "**PostgreSQL** (Primary)" as postgres_primary #4EA7FF
  collections "**PostgreSQL** (Secondary) x2" as postgres_secondary #4EA7FF

  pgbouncer -[#4EA7FF]-> postgres_primary
  postgres_primary .[#4EA7FF]> postgres_secondary
}

card "redis" as redis {
  collections "**Redis** x3" as redis_nodes #FF6347
}

cloud "**Object Storage**" as object_storage #white

elb -[#6a9be7]-> gitlab
elb -[hidden]-> sidekiq
elb -[hidden]-> support

gitlab -[#32CD32]--> ilb
gitlab -[#32CD32]r--> object_storage
gitlab -[#32CD32,norank]----> redis
gitlab -[#32CD32]----> database

sidekiq -[#ff8dd1]--> ilb
sidekiq -[#ff8dd1]r--> object_storage
sidekiq -[#ff8dd1,norank]----> redis
sidekiq .[#ff8dd1]----> database

ilb -[#9370DB]--> gitaly_cluster
ilb -[#9370DB]--> database
ilb -[hidden,norank]--> redis

consul .[#e76a9b]--> database
consul .[#e76a9b,norank]--> gitaly_cluster
consul .[#e76a9b]--> redis

@enduml

Resource usage settings

The following formulas help when calculating how many pods may be deployed within resource constraints. The 3k reference architecture example values file documents how to apply the calculated configuration to the Helm Chart.

Webservice

Webservice pods typically need about 1 CPU and 1.25 GB of memory per worker. Each Webservice pod consumes roughly 4 CPUs and 5 GB of memory using the recommended topology because four worker processes are created by default and each pod has other small processes running.

For 3,000 users we recommend a total Puma worker count of around 16. With the provided recommendations this allows the deployment of up to 4 Webservice pods with 4 workers per pod and 2 pods per node. Expand available resources using the ratio of 1 CPU to 1.25 GB of memory per each worker process for each additional Webservice pod.

For further information on resource usage, see the Webservice resources.

Sidekiq

Sidekiq pods should generally have 0.9 CPU and 2 GB of memory.

The provided starting point allows the deployment of up to 8 Sidekiq pods. Expand available resources using the 0.9 CPU to 2 GB memory ratio for each additional pod.

For further information on resource usage, see the Sidekiq resources.

Supporting

The Supporting Node Pool is designed to house all supporting deployments that don't need to be on the Webservice and Sidekiq pools.

This includes various deployments related to the Cloud Provider's implementation and supporting GitLab deployments such as NGINX or GitLab Shell.

If you wish to make any additional deployments, such as for Monitoring, it's recommended to deploy these in this pool where possible and not in the Webservice or Sidekiq pools, as the Supporting pool has been designed specifically to accommodate several additional deployments. However, if your deployments don't fit into the pool as given, you can increase the node pool accordingly.