debian-mirror-gitlab/doc/administration/reference_architectures/25k_users.md
2020-11-24 15:15:51 +05:30

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Reference architecture: up to 25,000 users (PREMIUM ONLY)

This page describes GitLab reference architecture for up to 25,000 users. For a full list of reference architectures, see Available reference architectures.

  • Supported users (approximate): 25,000
  • High Availability: Yes
  • Test requests per second (RPS) rates: API: 500 RPS, Web: 50 RPS, Git: 50 RPS
Service Nodes Configuration GCP AWS Azure
External load balancing node 1 4 vCPU, 3.6GB memory n1-highcpu-4 c5.xlarge F4s v2
Consul 3 2 vCPU, 1.8GB memory n1-highcpu-2 c5.large F2s v2
PostgreSQL 3 8 vCPU, 30GB memory n1-standard-8 m5.2xlarge D8s v3
PgBouncer 3 2 vCPU, 1.8GB memory n1-highcpu-2 c5.large F2s v2
Internal load balancing node 1 2 vCPU, 1.8GB memory n1-highcpu-2 c5.large F2s v2
Redis - Cache 3 4 vCPU, 15GB memory n1-standard-4 m5.xlarge D4s v3
Redis - Queues / Shared State 3 4 vCPU, 15GB memory n1-standard-4 m5.xlarge D4s v3
Redis Sentinel - Cache 3 1 vCPU, 1.7GB memory g1-small t2.small B1MS
Redis Sentinel - Queues / Shared State 3 1 vCPU, 1.7GB memory g1-small t2.small B1MS
Gitaly 2 (minimum) 32 vCPU, 120GB memory n1-standard-32 m5.8xlarge D32s v3
Sidekiq 4 4 vCPU, 15GB memory n1-standard-4 m5.xlarge D4s v3
GitLab Rails 5 32 vCPU, 28.8GB memory n1-highcpu-32 c5.9xlarge F32s v2
Monitoring node 1 4 vCPU, 3.6GB memory n1-highcpu-4 c5.xlarge F4s v2
Object Storage n/a n/a n/a n/a n/a
NFS Server 1 4 vCPU, 3.6GB memory n1-highcpu-4 c5.xlarge F4s v2

The Google Cloud Platform (GCP) architectures were built and tested using the Intel Xeon E5 v3 (Haswell) CPU platform. On different hardware you may find that adjustments, either lower or higher, are required for your CPU or node counts. For more information, see our Sysbench-based CPU benchmark.

For data objects (such as LFS, Uploads, or Artifacts), an object storage service is recommended instead of NFS where possible, due to better performance and availability. Since this doesn't require a node to be set up, Object Storage is noted as not applicable (n/a) in the previous table.

Setup components

To set up GitLab and its components to accommodate up to 25,000 users:

  1. Configure the external load balancing node that will handle the load balancing of the three GitLab application services nodes.
  2. Configure Consul.
  3. Configure PostgreSQL, the database for GitLab.
  4. Configure PgBouncer.
  5. Configure the internal load balancing node
  6. Configure Redis.
  7. Configure Gitaly, which provides access to the Git repositories.
  8. Configure Sidekiq.
  9. Configure the main GitLab Rails application to run Puma/Unicorn, Workhorse, GitLab Shell, and to serve all frontend requests (UI, API, Git over HTTP/SSH).
  10. Configure Prometheus to monitor your GitLab environment.
  11. Configure the Object Storage used for shared data objects.
  12. Configure NFS (Optional) to have shared disk storage service as an alternative to Gitaly and/or Object Storage (although not recommended). NFS is required for GitLab Pages, you can skip this step if you're not using that feature.

We start with all servers on the same 10.6.0.0/24 private network range, they can connect to each other freely on those addresses.

Here is a list and description of each machine and the assigned IP:

  • 10.6.0.10: External Load Balancer
  • 10.6.0.11: Consul 1
  • 10.6.0.12: Consul 2
  • 10.6.0.13: Consul 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
  • 10.6.0.40: Internal Load Balancer
  • 10.6.0.51: Redis - Cache Primary
  • 10.6.0.52: Redis - Cache Replica 1
  • 10.6.0.53: Redis - Cache Replica 2
  • 10.6.0.71: Sentinel - Cache 1
  • 10.6.0.72: Sentinel - Cache 2
  • 10.6.0.73: Sentinel - Cache 3
  • 10.6.0.61: Redis - Queues Primary
  • 10.6.0.62: Redis - Queues Replica 1
  • 10.6.0.63: Redis - Queues Replica 2
  • 10.6.0.81: Sentinel - Queues 1
  • 10.6.0.82: Sentinel - Queues 2
  • 10.6.0.83: Sentinel - Queues 3
  • 10.6.0.91: Gitaly 1
  • 10.6.0.92: Gitaly 2
  • 10.6.0.101: Sidekiq 1
  • 10.6.0.102: Sidekiq 2
  • 10.6.0.103: Sidekiq 3
  • 10.6.0.104: Sidekiq 4
  • 10.6.0.111: GitLab application 1
  • 10.6.0.112: GitLab application 2
  • 10.6.0.113: GitLab application 3
  • 10.6.0.121: Prometheus

Configure the external load balancer

NOTE: Note: This architecture has been tested and validated with HAProxy as the load balancer. Although other load balancers with similar feature sets could also be used, those load balancers have not been validated.

In an active/active GitLab configuration, you will need a load balancer to route traffic to the application servers. The specifics on which load balancer to use or the exact configuration is beyond the scope of GitLab documentation. We hope that if you're managing multi-node systems like GitLab you have a load balancer of choice already. Some examples including HAProxy (open-source), F5 Big-IP LTM, and Citrix Net Scaler. This documentation will outline what ports and protocols you need to use with GitLab.

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 NGINX 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 NGINX proxied SSL documentation for details.

Load balancer terminates SSL with backend SSL

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

Traffic will also be secure between the load balancer(s) 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 NGINX HTTPS documentation for details on managing SSL certificates and configuring NGINX.

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

Configure Consul

The following IPs will be used as an example:

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

NOTE: Note: The configuration processes for the other servers in your reference architecture will use the /etc/gitlab/gitlab-secrets.json file from your Consul server to connect with the other servers.

To configure Consul:

  1. SSH into the server that will host Consul.

  2. Download/install the Omnibus GitLab Enterprise Edition package using steps 1 and 2 from the GitLab downloads page.

    • Make sure you select the correct Omnibus package, with the same version the GitLab application is running.
    • Do not complete any other steps on the download page.
  3. Edit /etc/gitlab/gitlab.rb and add the contents:

    roles ['consul_role']
    
    ## Enable service discovery for Prometheus
    consul['enable'] = true
    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'
    
    # Disable auto migrations
    gitlab_rails['auto_migrate'] = false
    
  4. Reconfigure Omnibus GitLab for the changes to take effect.

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

NOTE: Note: A Consul leader will be elected when the provisioning of the third Consul server is completed. Viewing the Consul logs sudo gitlab-ctl tail consul will display ...[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

Configure PostgreSQL

In this section, you'll be guided through configuring an external PostgreSQL database to be used with GitLab.

Provide your own PostgreSQL instance

If you're hosting GitLab on a cloud provider, you can optionally use a managed service for PostgreSQL. For example, AWS offers a managed Relational Database Service (RDS) that runs PostgreSQL.

If you use a cloud-managed service, or provide your own PostgreSQL:

  1. Set up PostgreSQL according to the database requirements document.
  2. Set up a gitlab username with a password of your choice. The gitlab user needs privileges to create the gitlabhq_production database.
  3. Configure the GitLab application servers with the appropriate details. This step is covered in Configuring the GitLab Rails application.

See Configure GitLab using an external PostgreSQL service for further configuration steps.

Standalone PostgreSQL using Omnibus GitLab

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 primary node

  1. SSH into the PostgreSQL primary node.

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

    # Disable all components except PostgreSQL and Repmgr and Consul
    roles ['postgres_role']
    
    # PostgreSQL configuration
    postgresql['listen_address'] = '0.0.0.0'
    postgresql['hot_standby'] = 'on'
    postgresql['wal_level'] = 'replica'
    postgresql['shared_preload_libraries'] = 'repmgr_funcs'
    
    # Disable automatic database migrations
    gitlab_rails['auto_migrate'] = false
    
    # Configure the Consul agent
    consul['services'] = %w(postgresql)
    
    # 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_PASSWORD_HASH with a generated md5 value
    postgresql['sql_user_password'] = '<postgresql_password_hash>'
    # Set `max_wal_senders` to one more than the number of database nodes in the cluster.
    # This is used to prevent replication from using up all of the
    # available database connections.
    postgresql['max_wal_senders'] = 4
    postgresql['max_replication_slots'] = 4
    
    # Replace XXX.XXX.XXX.XXX/YY with Network Address
    postgresql['trust_auth_cidr_addresses'] = %w(10.6.0.0/24)
    repmgr['trust_auth_cidr_addresses'] = %w(127.0.0.1/32 10.6.0.0/24)
    
    ## Enable service discovery for Prometheus
    consul['monitoring_service_discovery'] =  true
    
    # 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
    
  6. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

  7. Reconfigure GitLab for the changes to take effect.

PostgreSQL secondary nodes

  1. On both the secondary nodes, add the same configuration specified above for the primary node with an additional setting (repmgr['master_on_initialization'] = false) that will inform gitlab-ctl that they are standby nodes initially and there's no need to attempt to register them as a primary node:

    # Disable all components except PostgreSQL and Repmgr and Consul
    roles ['postgres_role']
    
    # PostgreSQL configuration
    postgresql['listen_address'] = '0.0.0.0'
    postgresql['hot_standby'] = 'on'
    postgresql['wal_level'] = 'replica'
    postgresql['shared_preload_libraries'] = 'repmgr_funcs'
    
    # Disable automatic database migrations
    gitlab_rails['auto_migrate'] = false
    
    # Configure the Consul agent
    consul['services'] = %w(postgresql)
    
    # Specify if a node should attempt to be primary on initialization.
    repmgr['master_on_initialization'] = false
    
    # Replace PGBOUNCER_PASSWORD_HASH with a generated md5 value
    postgresql['pgbouncer_user_password'] = '<pgbouncer_password_hash>'
    # Replace POSTGRESQL_PASSWORD_HASH with a generated md5 value
    postgresql['sql_user_password'] = '<postgresql_password_hash>'
    # Set `max_wal_senders` to one more than the number of database nodes in the cluster.
    # This is used to prevent replication from using up all of the
    # available database connections.
    postgresql['max_wal_senders'] = 4
    postgresql['max_replication_slots'] = 4
    
    # Replace with your network addresses
    postgresql['trust_auth_cidr_addresses'] = %w(10.6.0.0/24)
    repmgr['trust_auth_cidr_addresses'] = %w(127.0.0.1/32 10.6.0.0/24)
    
    ## Enable service discovery for Prometheus
    consul['monitoring_service_discovery'] =  true
    
    # 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),
    }
    
  2. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

  3. Reconfigure GitLab for the changes to take effect.

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

PostgreSQL post-configuration

SSH into the primary node:

  1. Open a database prompt:

    gitlab-psql -d gitlabhq_production
    
  2. Make sure the pg_trgm extension is enabled (it might already be):

    CREATE EXTENSION pg_trgm;
    
  3. Exit the database prompt by typing \q and Enter.

  4. Verify the cluster is initialized with one node:

    gitlab-ctl repmgr cluster show
    

    The output should be similar to the following:

    Role      | Name     | Upstream | Connection String
    ----------+----------|----------|----------------------------------------
    * master  | HOSTNAME |          | host=HOSTNAME user=gitlab_repmgr dbname=gitlab_repmgr
    
  5. Note down the hostname or IP address in the connection string: host=HOSTNAME. We will refer to the hostname in the next section as <primary_node_name>. If the value is not an IP address, it will need to be a resolvable name (via DNS or /etc/hosts)

SSH into the secondary node:

  1. Set up the repmgr standby:

    gitlab-ctl repmgr standby setup <primary_node_name>
    

    Do note that this will remove the existing data on the node. The command has a wait time.

    The output should be similar to the following:

    Doing this will delete the entire contents of /var/opt/gitlab/postgresql/data
    If this is not what you want, hit Ctrl-C now to exit
    To skip waiting, rerun with the -w option
    Sleeping for 30 seconds
    Stopping the database
    Removing the data
    Cloning the data
    Starting the database
    Registering the node with the cluster
    ok: run: repmgrd: (pid 19068) 0s
    

Before moving on, make sure the databases are configured correctly. Run the following command on the primary node to verify that replication is working properly and the secondary nodes appear in the cluster:

gitlab-ctl repmgr cluster show

The output should be similar to the following:

Role      | Name    | Upstream  | Connection String
----------+---------|-----------|------------------------------------------------
* master  | MASTER  |           | host=<primary_node_name> user=gitlab_repmgr dbname=gitlab_repmgr
   standby | STANDBY | MASTER    | host=<secondary_node_name> user=gitlab_repmgr dbname=gitlab_repmgr
   standby | STANDBY | MASTER    | host=<secondary_node_name> user=gitlab_repmgr dbname=gitlab_repmgr

If the 'Role' column for any node says "FAILED", check the Troubleshooting section before proceeding.

Also, check that the repmgr-check-master command works successfully on each node:

su - gitlab-consul
gitlab-ctl repmgr-check-master || echo 'This node is a standby repmgr node'

This command relies on exit codes to tell Consul whether a particular node is a master or secondary. The most important thing here is that this command does not produce errors. If there are errors it's most likely due to incorrect gitlab-consul database user permissions. Check the Troubleshooting section before proceeding.

Configure PgBouncer

Now that the PostgreSQL servers are all set up, let's configure PgBouncer. 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['enable'] = true
    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'
    
  2. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

  3. Reconfigure Omnibus GitLab for the changes to take effect.

    NOTE: Note: If an error execute[generate databases.ini] occurs, this is due to an existing known issue. It will be resolved when you run a second reconfigure after the next step.

  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. Reconfigure GitLab once again to resolve any potential errors from the previous steps.

  6. Ensure each node is talking to the current primary:

    gitlab-ctl pgb-console # You will be prompted for PGBOUNCER_PASSWORD
    
  7. 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)
    

Configure the internal load balancer

If you're running more than one PgBouncer node as recommended, then at this time you'll need to set up a TCP internal load balancer to serve each correctly.

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

backend pgbouncer
    mode tcp
    option tcp-check

    server pgbouncer1 10.6.0.21:6432 check
    server pgbouncer2 10.6.0.22:6432 check
    server pgbouncer3 10.6.0.23:6432 check

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

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.

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.

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.

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

  • 10.6.0.51: Redis - Cache Primary
  • 10.6.0.52: Redis - Cache Replica 1
  • 10.6.0.53: Redis - Cache Replica 2
  • 10.6.0.71: Sentinel - Cache 1
  • 10.6.0.72: Sentinel - Cache 2
  • 10.6.0.73: Sentinel - Cache 3
  • 10.6.0.61: Redis - Queues Primary
  • 10.6.0.62: Redis - Queues Replica 1
  • 10.6.0.63: Redis - Queues Replica 2
  • 10.6.0.81: Sentinel - Queues 1
  • 10.6.0.82: Sentinel - Queues 2
  • 10.6.0.83: Sentinel - Queues 3

NOTE: Providing your own Redis instance: Managed Redis from cloud providers such as AWS ElastiCache will work. If these services support high availability, be sure it is not the Redis Cluster type. Redis version 5.0 or higher is required, as this is what ships with Omnibus GitLab packages starting with GitLab 13.0. Older Redis versions do not support an optional count argument to SPOP which is now required for Merge Trains. Note the Redis node's IP address or hostname, port, and password (if required). These will be necessary when configuring the GitLab application servers later.

Configure the Redis and Sentinel Cache cluster

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

NOTE: Note: Redis nodes (both primary and replica) will 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.

Configure the primary Redis Cache node

  1. SSH into the Primary Redis server.

  2. Download/install the Omnibus GitLab package you want using steps 1 and 2 from the GitLab downloads page.

    • Make sure you select the correct Omnibus package, with the same version and type (Community, Enterprise editions) of your current install.
    • Do not complete any other steps on the download page.
  3. Edit /etc/gitlab/gitlab.rb and add the contents:

    # Specify server role as 'redis_master_role'
    roles ['redis_master_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'] = '10.6.0.51'
    
    # 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_PRIMARY_PASSWORD_OF_FIRST_CLUSTER'
    
    ## Enable service discovery for Prometheus
    consul['enable'] = true
    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'
    
    # Prevent database migrations from running on upgrade
    gitlab_rails['auto_migrate'] = false
    
  4. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

  5. Reconfigure Omnibus GitLab for the changes to take effect.

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

Configure the replica Redis Cache nodes

  1. SSH into the replica Redis server.

  2. Download/install the Omnibus GitLab package you want using steps 1 and 2 from the GitLab downloads page.

    • Make sure you select the correct Omnibus package, with the same version and type (Community, Enterprise editions) of your current install.
    • Do not complete any other steps on the download page.
  3. Edit /etc/gitlab/gitlab.rb and add the contents:

    # Specify server role as 'redis_replica_role'
    roles ['redis_replica_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'] = '10.6.0.52'
    
    # 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_PRIMARY_PASSWORD_OF_FIRST_CLUSTER'
    
    # The IP of the primary Redis node.
    redis['master_ip'] = '10.6.0.51'
    
    # Port of primary Redis server, uncomment to change to non default. Defaults
    # to `6379`.
    #redis['master_port'] = 6379
    
    ## Enable service discovery for Prometheus
    consul['enable'] = true
    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'
    
    # Prevent database migrations from running on upgrade
    gitlab_rails['auto_migrate'] = false
    
  4. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

  5. Reconfigure Omnibus 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.

NOTE: Note: 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 the Sentinel Cache nodes

NOTE: Note: If you are using an external Redis Sentinel instance, be sure to exclude the requirepass parameter from the Sentinel configuration. This parameter will cause clients to report NOAUTH Authentication required.. Redis Sentinel 3.2.x does not support password authentication.

Now that the Redis servers are all set up, let's configure the Sentinel servers. The following IPs will be used as an example:

  • 10.6.0.71: Sentinel - Cache 1
  • 10.6.0.72: Sentinel - Cache 2
  • 10.6.0.73: Sentinel - Cache 3

To configure the Sentinel Cache server:

  1. SSH into the server that will host Consul/Sentinel.

  2. Download/install the Omnibus GitLab Enterprise Edition package using steps 1 and 2 from the GitLab downloads page.

    • Make sure you select the correct Omnibus package, with the same version the GitLab application is running.
    • Do not complete any other steps on the download page.
  3. Edit /etc/gitlab/gitlab.rb and add the contents:

    roles ['redis_sentinel_role']
    
    ## Must be the same in every sentinel node
    redis['master_name'] = 'gitlab-redis-cache'
    
    ## The same password for Redis authentication you set up for the primary node.
    redis['master_password'] = 'REDIS_PRIMARY_PASSWORD_OF_FIRST_CLUSTER'
    
    ## The IP of the primary Redis node.
    redis['master_ip'] = '10.6.0.51'
    
    ## 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's IP
    sentinel['bind'] = '10.6.0.71'
    
    ## 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['enable'] = true
    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'
    
    # Disable auto migrations
    gitlab_rails['auto_migrate'] = false
    
  4. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

  5. Reconfigure Omnibus 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.

Configure the Redis and Sentinel Queues cluster

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

NOTE: Note: Redis nodes (both primary and replica) will 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.

Configure the primary Redis Queues node

  1. SSH into the Primary Redis server.

  2. Download/install the Omnibus GitLab package you want using steps 1 and 2 from the GitLab downloads page.

    • Make sure you select the correct Omnibus package, with the same version and type (Community, Enterprise editions) of your current install.
    • Do not complete any other steps on the download page.
  3. Edit /etc/gitlab/gitlab.rb and add the contents:

    # Specify server role as 'redis_master_role'
    roles ['redis_master_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_PRIMARY_PASSWORD_OF_SECOND_CLUSTER'
    
    ## Enable service discovery for Prometheus
    consul['enable'] = true
    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'
    
  4. Only the primary GitLab application server should handle migrations. To prevent database migrations from running on upgrade, add the following configuration to your /etc/gitlab/gitlab.rb file:

    gitlab_rails['auto_migrate'] = false
    
  5. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

  6. Reconfigure Omnibus GitLab for the changes to take effect.

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

Configure the replica Redis Queues nodes

  1. SSH into the replica Redis Queue server.

  2. Download/install the Omnibus GitLab package you want using steps 1 and 2 from the GitLab downloads page.

    • Make sure you select the correct Omnibus package, with the same version and type (Community, Enterprise editions) of your current install.
    • Do not complete any other steps on the download page.
  3. Edit /etc/gitlab/gitlab.rb and add the contents:

    # Specify server role as 'redis_replica_role'
    roles ['redis_replica_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_PRIMARY_PASSWORD_OF_SECOND_CLUSTER'
    
    # 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['enable'] = true
    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'
    
    # Disable auto migrations
    gitlab_rails['auto_migrate'] = false
    
  4. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

  5. Reconfigure Omnibus 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.

NOTE: Note: 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 the Sentinel Queues nodes

NOTE: Note: If you are using an external Redis Sentinel instance, be sure to exclude the requirepass parameter from the Sentinel configuration. This parameter will cause clients to report NOAUTH Authentication required.. Redis Sentinel 3.2.x does not support password authentication.

Now that the Redis servers are all set up, let's configure the Sentinel servers. The following IPs will be used as an example:

  • 10.6.0.81: Sentinel - Queues 1
  • 10.6.0.82: Sentinel - Queues 2
  • 10.6.0.83: Sentinel - Queues 3

To configure the Sentinel Queues server:

  1. SSH into the server that will host Sentinel.

  2. Download/install the Omnibus GitLab Enterprise Edition package using steps 1 and 2 from the GitLab downloads page.

    • Make sure you select the correct Omnibus package, with the same version the GitLab application is running.
    • Do not complete any other steps on the download page.
  3. Edit /etc/gitlab/gitlab.rb and add the contents:

    roles ['redis_sentinel_role']
    
    ## Must be the same in every sentinel node
    redis['master_name'] = 'gitlab-redis-persistent'
    
    ## The same password for Redis authentication you set up for the primary node.
    redis['master_password'] = 'REDIS_PRIMARY_PASSWORD_OF_SECOND_CLUSTER'
    
    ## 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's IP
    sentinel['bind'] = '10.6.0.81'
    
    ## 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['enable'] = true
    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'
    
    # Disable auto migrations
    gitlab_rails['auto_migrate'] = false
    
  4. To prevent database migrations from running on upgrade, run:

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

    Only the primary GitLab application server should handle migrations.

  5. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

  6. Reconfigure Omnibus GitLab for the changes to take effect.

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

Configure Gitaly

Deploying Gitaly in its own server can benefit GitLab installations that are larger than a single machine.

The Gitaly node requirements are dependent on customer data, specifically the number of projects and their repository sizes. Two nodes are recommended as an absolute minimum. Each Gitaly node should store no more than 5TB of data and have the number of gitaly-ruby workers set to 20% of available CPUs. Additional nodes should be considered in conjunction with a review of expected data size and spread based on the recommendations above.

It is also strongly recommended that all Gitaly nodes be set up with SSD disks with a throughput of at least 8,000 IOPS for read operations and 2,000 IOPS for write, as Gitaly has heavy I/O. These IOPS values are recommended only as a starter as with time they may be adjusted higher or lower depending on the scale of your environment's workload. If you're running the environment on a Cloud provider, you may need to refer to their documentation on how to configure IOPS correctly.

Some things to note:

  • The GitLab Rails application shards repositories into repository storages.
  • A Gitaly server can host one or more storages.
  • A GitLab server can use one or more Gitaly servers.
  • Gitaly addresses must be specified in such a way that they resolve correctly for ALL Gitaly clients.
  • 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.

TIP: Tip: For more information about Gitaly's history and network architecture see the standalone Gitaly documentation.

Note: Note: The token referred to throughout the Gitaly documentation is just an arbitrary password selected by the administrator. It is unrelated to tokens created for the GitLab API or other similar web API tokens.

Below we describe how to configure two Gitaly servers, with IPs and domain names:

  • 10.6.0.91: Gitaly 1 (gitaly1.internal)
  • 10.6.0.92: Gitaly 2 (gitaly2.internal)

The secret token is assumed to be gitalysecret and that your GitLab installation has three repository storages:

  • default on Gitaly 1
  • storage1 on Gitaly 1
  • storage2 on Gitaly 2

On each node:

  1. Download/Install the Omnibus GitLab package you want using steps 1 and 2 from the GitLab downloads page but without providing the EXTERNAL_URL value.

  2. Edit /etc/gitlab/gitlab.rb to configure storage paths, enable the network listener and configure the token:

    # /etc/gitlab/gitlab.rb
    
    # Gitaly and GitLab use two shared secrets for authentication, one to authenticate gRPC requests
    # to Gitaly, and a second for authentication callbacks from GitLab-Shell to the GitLab internal API.
    # The following two values must be the same as their respective values
    # of the GitLab Rails application setup
    gitaly['auth_token'] = 'gitalysecret'
    gitlab_shell['secret_token'] = 'shellsecret'
    
    # Avoid running unnecessary services on the Gitaly server
    postgresql['enable'] = false
    redis['enable'] = false
    nginx['enable'] = false
    puma['enable'] = false
    unicorn['enable'] = false
    sidekiq['enable'] = false
    gitlab_workhorse['enable'] = false
    grafana['enable'] = false
    
    # If you run a separate monitoring node you can disable these services
    alertmanager['enable'] = false
    prometheus['enable'] = false
    
    # Prevent database connections during 'gitlab-ctl reconfigure'
    gitlab_rails['rake_cache_clear'] = false
    gitlab_rails['auto_migrate'] = false
    
    # 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.
    # Don't forget to copy `/etc/gitlab/gitlab-secrets.json` from web server to Gitaly server.
    gitlab_rails['internal_api_url'] = 'https://gitlab.example.com'
    
    # 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
    gitaly['listen_addr'] = "0.0.0.0:8075"
    
  3. Append the following to /etc/gitlab/gitlab.rb for each respective server:

    1. On gitaly1.internal:

      git_data_dirs({
        'default' => {
          'path' => '/var/opt/gitlab/git-data'
        },
        'storage1' => {
          'path' => '/mnt/gitlab/git-data'
        },
      })
      
    2. On gitaly2.internal:

      git_data_dirs({
        'storage2' => {
          'path' => '/mnt/gitlab/git-data'
        },
      })
      
  4. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

  5. Save the file and reconfigure GitLab.

Gitaly TLS support

Gitaly supports TLS encryption. To be able to communicate with a Gitaly instance that listens for secure connections you will need to use tls:// URL scheme in the gitaly_address of the corresponding storage entry in the GitLab configuration.

You will need to bring your own certificates as this isn't provided automatically. The certificate, or its certificate authority, must be installed on all Gitaly nodes (including the Gitaly node using the certificate) and on all client nodes that communicate with it following the procedure described in GitLab custom certificate configuration.

NOTE: Note: The self-signed certificate must specify the address you use to access the Gitaly server. If you are addressing the Gitaly server by a hostname, you can either use the Common Name field for this, or add it as a Subject Alternative Name. If you are addressing the Gitaly server by its IP address, you must add it as a Subject Alternative Name to the certificate. gRPC does not support using an IP address as Common Name in a certificate.

NOTE: Note: It is possible to configure Gitaly 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 configure Gitaly with TLS:

  1. 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
    
  2. Copy the cert to /etc/gitlab/trusted-certs so Gitaly will trust the cert when calling into itself:

    sudo cp /etc/gitlab/ssl/cert.pem /etc/gitlab/trusted-certs/
    
  3. Edit /etc/gitlab/gitlab.rb and add:

    gitaly['tls_listen_addr'] = "0.0.0.0:9999"
    gitaly['certificate_path'] = "/etc/gitlab/ssl/cert.pem"
    gitaly['key_path'] = "/etc/gitlab/ssl/key.pem"
    
  4. Delete gitaly['listen_addr'] to allow only encrypted connections.

  5. Save the file and reconfigure GitLab.

Configure Sidekiq

Sidekiq requires connections to the Redis, PostgreSQL and Gitaly instances. The following IPs will be used as an example:

  • 10.6.0.101: Sidekiq 1
  • 10.6.0.102: Sidekiq 2
  • 10.6.0.103: Sidekiq 3
  • 10.6.0.104: Sidekiq 4

To configure the Sidekiq nodes, on each one:

  1. SSH into the Sidekiq server.

  2. Download/install the Omnibus GitLab package you want using steps 1 and 2 from the GitLab downloads page. Do not complete any other steps on the download page.

  3. Open /etc/gitlab/gitlab.rb with your editor:

    ########################################
    #####        Services Disabled       ###
    ########################################
    
    nginx['enable'] = false
    grafana['enable'] = false
    prometheus['enable'] = false
    alertmanager['enable'] = false
    gitaly['enable'] = false
    gitlab_workhorse['enable'] = false
    nginx['enable'] = false
    puma['enable'] = false
    postgres_exporter['enable'] = false
    postgresql['enable'] = false
    redis['enable'] = false
    redis_exporter['enable'] = false
    gitlab_exporter['enable'] = false
    
    ########################################
    ####              Redis              ###
    ########################################
    
    ## Redis connection details
    ## First cluster that will host the cache
    gitlab_rails['redis_cache_instance'] = 'redis://:<REDIS_PRIMARY_PASSWORD_OF_FIRST_CLUSTER>@gitlab-redis-cache'
    
    gitlab_rails['redis_cache_sentinels'] = [
      {host: '10.6.0.71', port: 26379},
      {host: '10.6.0.72', port: 26379},
      {host: '10.6.0.73', port: 26379},
    ]
    
    ## Second cluster that will host the queues, shared state, and actioncable
    gitlab_rails['redis_queues_instance'] = 'redis://:<REDIS_PRIMARY_PASSWORD_OF_SECOND_CLUSTER>@gitlab-redis-persistent'
    gitlab_rails['redis_shared_state_instance'] = 'redis://:<REDIS_PRIMARY_PASSWORD_OF_SECOND_CLUSTER>@gitlab-redis-persistent'
    gitlab_rails['redis_actioncable_instance'] = 'redis://:<REDIS_PRIMARY_PASSWORD_OF_SECOND_CLUSTER>@gitlab-redis-persistent'
    
    gitlab_rails['redis_queues_sentinels'] = [
      {host: '10.6.0.81', port: 26379},
      {host: '10.6.0.82', port: 26379},
      {host: '10.6.0.83', port: 26379},
    ]
    gitlab_rails['redis_shared_state_sentinels'] = [
      {host: '10.6.0.81', port: 26379},
      {host: '10.6.0.82', port: 26379},
      {host: '10.6.0.83', port: 26379},
    ]
    gitlab_rails['redis_actioncable_sentinels'] = [
      {host: '10.6.0.81', port: 26379},
      {host: '10.6.0.82', port: 26379},
      {host: '10.6.0.83', port: 26379},
    ]
    
    #######################################
    ###              Gitaly             ###
    #######################################
    
    git_data_dirs({
      'default' => { 'gitaly_address' => 'tcp://gitaly1.internal:8075' },
      'storage1' => { 'gitaly_address' => 'tcp://gitaly1.internal:8075' },
      'storage2' => { 'gitaly_address' => 'tcp://gitaly2.internal:8075' },
    })
    gitlab_rails['gitaly_token'] = 'YOUR_TOKEN'
    
    #######################################
    ###            Postgres             ###
    #######################################
    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_adapter'] = 'postgresql'
    gitlab_rails['db_encoding'] = 'unicode'
    gitlab_rails['auto_migrate'] = false
    
    #######################################
    ###      Sidekiq configuration      ###
    #######################################
    sidekiq['listen_address'] = "0.0.0.0"
    sidekiq['cluster'] = true # no need to set this after GitLab 13.0
    
    #######################################
    ###     Monitoring configuration    ###
    #######################################
    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'
    
    # Rails Status for prometheus
    gitlab_rails['monitoring_whitelist'] = ['10.6.0.121/32', '127.0.0.0/8']
    
  4. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

  5. Reconfigure GitLab for the changes to take effect.

TIP: Tip: You can also run multiple Sidekiq processes.

Configure GitLab Rails

NOTE: Note: In our architectures we run each GitLab Rails node using the Puma webserver and have its number of workers set to 90% of available CPUs along with four threads. For nodes that are running Rails with other components the worker value should be reduced accordingly where we've found 50% achieves a good balance but this is dependent on workload.

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

The following IPs will be used as an example:

  • 10.6.0.111: GitLab application 1
  • 10.6.0.112: GitLab application 2
  • 10.6.0.113: GitLab application 3

On each node perform the following:

  1. Download/install Omnibus GitLab using steps 1 and 2 from GitLab downloads. Do not complete other steps on the download page.

  2. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

  3. 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'
    
    # Gitaly and GitLab use two shared secrets for authentication, one to authenticate gRPC requests
    # to Gitaly, and a second for authentication callbacks from GitLab-Shell to the GitLab internal API.
    # The following two values must be the same as their respective values
    # of the Gitaly setup
    gitlab_rails['gitaly_token'] = 'gitalysecret'
    gitlab_shell['secret_token'] = 'shellsecret'
    
    git_data_dirs({
      'default' => { 'gitaly_address' => 'tcp://gitaly1.internal:8075' },
      'storage1' => { 'gitaly_address' => 'tcp://gitaly1.internal:8075' },
      'storage2' => { 'gitaly_address' => 'tcp://gitaly2.internal:8075' },
    })
    
    ## Disable components that will not be on the GitLab application server
    roles ['application_role']
    gitaly['enable'] = false
    nginx['enable'] = true
    
    ## 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['auto_migrate'] = false
    
    ## Redis connection details
    ## First cluster that will host the cache
    gitlab_rails['redis_cache_instance'] = 'redis://:<REDIS_PRIMARY_PASSWORD_OF_FIRST_CLUSTER>@gitlab-redis-cache'
    
    gitlab_rails['redis_cache_sentinels'] = [
      {host: '10.6.0.71', port: 26379},
      {host: '10.6.0.72', port: 26379},
      {host: '10.6.0.73', port: 26379},
    ]
    
    ## Second cluster that will host the queues, shared state, and actionable
    gitlab_rails['redis_queues_instance'] = 'redis://:<REDIS_PRIMARY_PASSWORD_OF_SECOND_CLUSTER>@gitlab-redis-persistent'
    gitlab_rails['redis_shared_state_instance'] = 'redis://:<REDIS_PRIMARY_PASSWORD_OF_SECOND_CLUSTER>@gitlab-redis-persistent'
    gitlab_rails['redis_actioncable_instance'] = 'redis://:<REDIS_PRIMARY_PASSWORD_OF_SECOND_CLUSTER>@gitlab-redis-persistent'
    
    gitlab_rails['redis_queues_sentinels'] = [
      {host: '10.6.0.81', port: 26379},
      {host: '10.6.0.82', port: 26379},
      {host: '10.6.0.83', port: 26379},
    ]
    gitlab_rails['redis_shared_state_sentinels'] = [
      {host: '10.6.0.81', port: 26379},
      {host: '10.6.0.82', port: 26379},
      {host: '10.6.0.83', port: 26379},
    ]
    gitlab_rails['redis_actioncable_sentinels'] = [
      {host: '10.6.0.81', port: 26379},
      {host: '10.6.0.82', port: 26379},
      {host: '10.6.0.83', port: 26379},
    ]
    
    # 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'
    
    # Add the monitoring node's IP address to the monitoring whitelist and allow it to
    # scrape the NGINX metrics
    gitlab_rails['monitoring_whitelist'] = ['10.6.0.121/32', '127.0.0.0/8']
    nginx['status']['options']['allow'] = ['10.6.0.121/32', '127.0.0.0/8']
    
  4. Save the file and reconfigure GitLab.

  5. 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://gitaly1.internal:9999' },
      'storage1' => { 'gitaly_address' => 'tls://gitaly1.internal:9999' },
      'storage2' => { 'gitaly_address' => 'tls://gitaly2.internal:9999' },
    })
    
    1. Copy the cert into /etc/gitlab/trusted-certs:

      sudo cp cert.pem /etc/gitlab/trusted-certs/
      
  6. If you're using NFS:

    1. If necessary, install the NFS client utility packages using the following commands:

      # Ubuntu/Debian
      apt-get install nfs-common
      
      # CentOS/Red Hat
      yum install nfs-utils nfs-utils-lib
      
    2. Specify the necessary NFS mounts in /etc/fstab. The exact contents of /etc/fstab will depend on how you chose to configure your NFS server. See the NFS documentation for examples and the various options.

    3. Create the shared directories. These may be different depending on your NFS mount locations.

      mkdir -p /var/opt/gitlab/.ssh /var/opt/gitlab/gitlab-rails/uploads /var/opt/gitlab/gitlab-rails/shared /var/opt/gitlab/gitlab-ci/builds /var/opt/gitlab/git-data
      
    4. Edit /etc/gitlab/gitlab.rb and use the following configuration:

      ## 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
      
  7. Save the file and reconfigure GitLab.

  8. Confirm the node can connect to Gitaly:

    sudo gitlab-rake gitlab:gitaly:check
    

    Then, tail the logs to see the requests:

    sudo gitlab-ctl tail gitaly
    
  9. Optionally, from the Gitaly servers, confirm that Gitaly can perform callbacks to the internal API:

    sudo /opt/gitlab/embedded/service/gitlab-shell/bin/check -config /opt/gitlab/embedded/service/gitlab-shell/config.yml
    

NOTE: Note: When you specify https in the external_url, as in the example above, GitLab assumes you have SSL certificates in /etc/gitlab/ssl/. If certificates are not present, NGINX will fail to start. See the NGINX documentation for more information.

GitLab Rails post-configuration

Initialize the GitLab database, by running the following in one of the Rails nodes:

sudo gitlab-rake gitlab:db:configure

NOTE: Note: If you encounter a rake aborted! error stating that PgBouncer is failing to connect to PostgreSQL it may be that your PgBouncer node's IP address is missing from PostgreSQL's trust_auth_cidr_addresses in gitlab.rb on your database nodes. See PgBouncer error ERROR: pgbouncer cannot connect to server in the Troubleshooting section before proceeding.

Configure Prometheus

The Omnibus GitLab package can be used to configure a standalone Monitoring node running Prometheus and Grafana.

The following IP will be used as an example:

  • 10.6.0.121: Prometheus

To configure the Monitoring node:

  1. SSH into the Monitoring node.

  2. Download/install the Omnibus GitLab package you want using steps 1 and 2 from the GitLab downloads page. Do not complete any other steps on the download page.

  3. Copy the /etc/gitlab/gitlab-secrets.json file from your Consul server, and replace the file of the same name on this server. If that file is not on this server, add the file from your Consul server to this server.

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

    external_url 'http://gitlab.example.com'
    
    # Disable all other services
    gitlab_rails['auto_migrate'] = false
    alertmanager['enable'] = false
    gitaly['enable'] = false
    gitlab_exporter['enable'] = false
    gitlab_workhorse['enable'] = false
    nginx['enable'] = true
    postgres_exporter['enable'] = false
    postgresql['enable'] = false
    redis['enable'] = false
    redis_exporter['enable'] = false
    sidekiq['enable'] = false
    puma['enable'] = false
    unicorn['enable'] = false
    node_exporter['enable'] = false
    gitlab_exporter['enable'] = false
    
    # Enable Prometheus
    prometheus['enable'] = true
    prometheus['listen_address'] = '0.0.0.0:9090'
    prometheus['monitor_kubernetes'] = false
    
    # Enable Login form
    grafana['disable_login_form'] = false
    
    # Enable Grafana
    grafana['enable'] = true
    grafana['admin_password'] = '<grafana_password>'
    
    # Enable service discovery for Prometheus
    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)
    }
    
  5. Save the file and reconfigure GitLab.

  6. In the GitLab UI, set admin/application_settings/metrics_and_profiling > Metrics - Grafana to /-/grafana to http[s]://<MONITOR NODE>/-/grafana

Configure the object storage

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

Object storage options that GitLab has tested, or is aware of customers using include:

For configuring GitLab to use Object Storage refer to the following guides based on what features you intend to use:

  1. Configure object storage for backups.
  2. Configure object storage for job artifacts including incremental logging.
  3. Configure object storage for LFS objects.
  4. Configure object storage for uploads.
  5. Configure object storage for merge request diffs.
  6. Configure object storage for Container Registry (optional feature).
  7. Configure object storage for Mattermost (optional feature).
  8. Configure object storage for packages (optional feature). (PREMIUM ONLY)
  9. Configure object storage for Dependency Proxy (optional feature). (PREMIUM ONLY)
  10. Configure object storage for Pseudonymizer (optional feature). (ULTIMATE ONLY)
  11. Configure object storage for autoscale runner caching (optional - for improved performance).
  12. Configure object storage for Terraform state files.

Using separate buckets for each data type is the recommended approach for GitLab.

A limitation of our configuration is that each use of object storage is separately configured. We have an issue for improving this and easily using one bucket with separate folders is one improvement that this might bring.

There is at least one specific issue with using the same bucket: when GitLab is deployed with the Helm chart restore from backup will not properly function unless separate buckets are used.

One risk of using a single bucket would be if your organization decided to migrate GitLab to the Helm deployment in the future. GitLab would run, but the situation with backups might not be realized until the organization had a critical requirement for the backups to work.

Configure NFS (optional)

Object storage, along with Gitaly are recommended over NFS wherever possible for improved performance. If you intend to use GitLab Pages, this currently requires NFS.

See how to configure NFS.

Troubleshooting

See the troubleshooting documentation.