• Requirements
• Overview
• Set up Omnibus database nodes
• Set up Kubernetes clusters
• Collect information
• Configure Primary database
• Deploy chart as Geo Primary site
• Set the Geo Primary site
• Configure Secondary database
• Copy secrets from the primary site to the secondary site
• Deploy chart as Geo Secondary site
• Add Secondary Geo site via Primary
• Confirm Operational Status

Configure the GitLab chart with GitLab Geo

GitLab Geo provides the ability to have geographically distributed application
deployments.

While external database services can be used, these documents focus on
the use of the Omnibus GitLab for PostgreSQL to provide the
most platform agnostic guide, and make use of the automation included in gitlab-ctl .

In this guide, both clusters have the same external URL. See Set up a Unified URL for Geo sites.

Requirements

To use GitLab Geo with the GitLab Helm chart, the following requirements must be met:

• The use of external PostgreSQL services, as the
  PostgresSQL included with the chart is not exposed to outside networks, and doesn’t
  have WAL support required for replication.
• The supplied database must:
  
  
  
  • Support replication.
  • The primary database must be reachable by the primary site,
    and all secondary database nodes (for replication).
  • Secondary databases only need to be reachable by the secondary sites.
  • Support SSL between primary and secondary database nodes.
• The primary site must be reachable via HTTP(S) by all secondary sites.
  Secondary sites must be accessible to the primary site via HTTP(S).

Overview

This guide uses 2 Omnibus GitLab database nodes,
configuring only the PostgreSQL services needed, and 2 deployments of the
GitLab Helm chart. It is intended to be the minimal required configuration.
This documentation does not include SSL from application to database, support
for other database providers, or
promoting a secondary site to primary.

The outline below should be followed in order:

1. Setup Omnibus database nodes
2. Setup Kubernetes clusters
3. Collect information
4. Configure Primary database
5. Deploy chart as Geo Primary site
6. Set the Geo primary site
7. Configure Secondary database
8. Copy secrets from primary site to secondary site
9. Deploy chart as Geo Secondary site
10. Add Secondary Geo site via Primary
11. Confirm Operational Status

Set up Omnibus database nodes

For this process, two nodes are required. One is the Primary database node, the
other the Secondary database node. You may use any provider of machine
infrastructure, on-premise or from a cloud provider.

Bear in mind that communication is required:

• Between the two database nodes for replication.
• Between each database node and their respective Kubernetes deployments:
  
  
  
  • The primary needs to expose TCP port 5432 .
  • The secondary needs to expose TCP ports 5432 & 5431 .

Install an operating system supported by Omnibus GitLab, and then
install the Omnibus GitLab onto it. Do not provide the
EXTERNAL_URL environment variable when installing, as we’ll provide a minimal
configuration file before reconfiguring the package.

After you have installed the operating system, and the GitLab package, configuration
can be created for the services that will be used. Before we do that, information
must be collected.

Set up Kubernetes clusters

For this process, two Kubernetes clusters should be used. These can be from any
provider, on-premise or from a cloud provider.

Bear in mind that communication is required:

• To the respective database nodes:
  
  
  
  • Primary outbound to TCP 5432 .
  • Secondary outbound to TCP 5432 and 5431 .
• Between both Kubernetes Ingress via HTTPS.

Each cluster that is provisioned should have:

• Enough resources to support a base-line installation of these charts.
• Access to persistent storage:
  
  
  
  • MinIO not required if using external object storage.
  • Gitaly not required if using external Gitaly.
  • Redis not required if using external Redis.

Collect information

To continue with the configuration, the following information needs to be
collected from the various sources. Collect these, and make notes for use through
the rest of this documentation.

• Primary database:
  
  
  
  • IP address
  • hostname (optional)
• Secondary database:
  
  
  
  • IP address
  • hostname (optional)
• Primary cluster:
  
  
  
  • External URL
  • Internal URL
  • IP addresses of nodes
• Secondary cluster:
  
  
  
  • Internal URL
  • IP addresses of nodes
• Database Passwords ( must pre-decide the passwords ):
  
  
  
  • 
    gitlab (used in postgresql['sql_user_password'] , global.psql.password )
  • 
    gitlab_geo (used in geo_postgresql['sql_user_password'] , global.geo.psql.password )
  • 
    gitlab_replicator (needed for replication)
• Your GitLab license file

The Internal URL of each cluster must be unique to the cluster, so that all
clusters can make requests to all other clusters. For example:

• External URL of all clusters: https://gitlab.example.com
  
• Primary cluster’s Internal URL: https://london.gitlab.example.com
  
• Secondary cluster’s Internal URL: https://shanghai.gitlab.example.com
  

This guide does not cover setting up DNS.

The gitlab and gitlab_geo database user passwords must exist in two
forms: bare password, and PostgreSQL hashed password. To obtain the hashed form,
perform the following commands on one of the Omnibus instances, which asks
you to enter and confirm the password before outputting an appropriate hash
value for you to make note of.

1. gitlab-ctl pg-password-md5 gitlab
2. gitlab-ctl pg-password-md5 gitlab_geo

Configure Primary database

This section is performed on the Primary Omnibus GitLab database node.

To configure the Primary database node’s Omnibus GitLab, work from
this example configuration:

### Geo Primary
external_url 'http://gitlab.example.com'
roles ['geo_primary_role']
# The unique identifier for the Geo node.
gitlab_rails['geo_node_name'] = 'London Office'
gitlab_rails['auto_migrate'] = false
## turn off everything but the DB
sidekiq['enable']=false
puma['enable']=false
gitlab_workhorse['enable']=false
nginx['enable']=false
geo_logcursor['enable']=false
grafana['enable']=false
gitaly['enable']=false
redis['enable']=false
prometheus_monitoring['enable'] = false
## Configure the DB for network
postgresql['enable'] = true
postgresql['listen_address'] = '0.0.0.0'
postgresql['sql_user_password'] = 'gitlab_user_password_hash'
# !! CAUTION !!
# This list of CIDR addresses should be customized
# - primary application deployment
# - secondary database node(s)
postgresql['md5_auth_cidr_addresses'] = ['0.0.0.0/0']

We must replace several items:

• 
  external_url must be updated to reflect the host name of our Primary site.
• 
  gitlab_rails['geo_node_name'] must be replaced with a unique name for your
  site. See the Name field in
  Common settings.
• 
  gitlab_user_password_hash must be replaced with the hashed form of the
  gitlab password.
• 
  postgresql['md5_auth_cidr_addresses'] can be update to be a list of
  explicit IP addresses, or address blocks in CIDR notation.

The md5_auth_cidr_addresses should be in the form of
[ '127.0.0.1/24', '10.41.0.0/16'] . It is important to include 127.0.0.1 in
this list, as the automation in Omnibus GitLab connects using this. The
addresses in this list should include the IP address (not hostname) of your
Secondary database, and all nodes of your primary Kubernetes cluster. This can
be left as ['0.0.0.0/0'] , however it is not best practice .

After the configuration above is prepared:

1. Place the content into /etc/gitlab/gitlab.rb
   
2. Run gitlab-ctl reconfigure . If you experience any issues in regards to the
   service not listening on TCP, try directly restarting it with
   gitlab-ctl restart postgresql .
3. Run gitlab-ctl set-replication-password to set the password for
   the gitlab_replicator user.
4. 
   

   Retrieve the Primary database node’s public certificate, this is needed
   for the Secondary database to be able to replicate (save this output):

   
   

   cat ~gitlab-psql/data/server.crt
   

Deploy chart as Geo Primary site

This section is performed on the Primary site’s Kubernetes cluster.

To deploy this chart as a Geo Primary, start from this example configuration:

1. 
   

   Create a secret containing the database password for the
   chart to consume. Replace PASSWORD below with the password for the gitlab
   database user:

   
   

   kubectl --namespace gitlab create secret generic geo --from-literal=postgresql-password=PASSWORD
   

2. 
   

   Create a primary.yaml file based on the example configuration
   and update the configuration to reflect the correct values:

   
   

   ### Geo Primary
   global:
     # See docs.gitlab.com/charts/charts/globals
     # Configure host & domain
     hosts:
       domain: example.com
     # configure DB connection
     psql:
       host: geo-1.db.example.com
       port: 5432
       password:
         secret: geo
         key: postgresql-password
     # configure geo (primary)
     geo:
       nodeName: London Office
       enabled: true
       role: primary
   # External DB, disable
   postgresql:
     install: false
   

   
   
   • global.hosts.domain
   • global.psql.host
   • global.geo.nodeName must match
     the Name field of a Geo site in the Admin Area
     
   • Also configure any additional settings, such as:
     
     
     
     • Configuring SSL/TLS
     • Using external Redis
     • 
       using external Object Storage
       
3. 
   

   Deploy the chart using this configuration:

   
   

   helm upgrade --install gitlab-geo gitlab/gitlab --namespace gitlab -f primary.yaml
   

   
   

   This assumes you are using the gitlab namespace. If you want to use a different namespace,
   you should also replace it in --namespace gitlab throughout the rest of this document.
4. 
   

   Wait for the deployment to complete, and the application to come online. When
   the application is reachable, log in.

5. 
   

   Sign in to GitLab, and activate your GitLab subscription.

   
   

   This step is required for Geo to function.

Set the Geo Primary site

Now that the chart has been deployed, and a license uploaded, we can configure
this as the Primary site. We will do this via the Toolbox Pod.

1. 
   

   Find the Toolbox Pod

   
   

   kubectl --namespace gitlab get pods -lapp=toolbox
   

2. 
   

   Run gitlab-rake geo:set_primary_node with kubectl exec :

   
   

   kubectl --namespace gitlab exec -ti gitlab-geo-toolbox-XXX -- gitlab-rake geo:set_primary_node
   

3. 
   

   Set the primary site’s Internal URL with a Rails runner command. Replace https://primary.gitlab.example.com with the actual Internal URL:

   
   

   kubectl --namespace gitlab exec -ti gitlab-geo-toolbox-XXX -- gitlab-rails runner "GeoNode.primary_node.update!(internal_url: 'https://primary.gitlab.example.com'"
   

4. 
   

   Check the status of Geo configuration:

   
   

   kubectl --namespace gitlab exec -ti gitlab-geo-toolbox-XXX -- gitlab-rake gitlab:geo:check
   

   You should see output similar to below:

   
   

   WARNING: This version of GitLab depends on gitlab-shell 10.2.0, but you're running Unknown. Please update gitlab-shell.
   Checking Geo ...
   
   GitLab Geo is available ... yes
   GitLab Geo is enabled ... yes
   GitLab Geo secondary database is correctly configured ... not a secondary node
   Database replication enabled? ... not a secondary node
   Database replication working? ... not a secondary node
   GitLab Geo HTTP(S) connectivity ... not a secondary node
   HTTP/HTTPS repository cloning is enabled ... yes
   Machine clock is synchronized ... Exception: getaddrinfo: Servname not supported for ai_socktype
   Git user has default SSH configuration? ... yes
   OpenSSH configured to use AuthorizedKeysCommand ... no
     Reason:
     Cannot find OpenSSH configuration file at: /assets/sshd_config
     Try fixing it:
     If you are not using our official docker containers,
     make sure you have OpenSSH server installed and configured correctly on this system
     For more information see:
     doc/administration/operations/fast_ssh_key_lookup.md
   GitLab configured to disable writing to authorized_keys file ... yes
   GitLab configured to store new projects in hashed storage? ... yes
   All projects are in hashed storage? ... yes
   
   Checking Geo ... Finished
   

   
   
   • Don’t worry about Exception: getaddrinfo: Servname not supported for ai_socktype , as Kubernetes containers don’t have access to the host clock. This is OK .
   • 
     OpenSSH configured to use AuthorizedKeysCommand ... no is expected . This
     Rake task is checking for a local SSH server, which is actually present in the
     gitlab-shell chart, deployed elsewhere, and already configured appropriately.

Configure Secondary database

This section is performed on the Secondary Omnibus GitLab database node.

To configure the Secondary database node’s Omnibus GitLab, work from
this example configuration:

### Geo Secondary
# external_url must match the Primary cluster's external_url
external_url 'http://gitlab.example.com'
roles ['geo_secondary_role']
gitlab_rails['enable'] = true
# The unique identifier for the Geo node.
gitlab_rails['geo_node_name'] = 'Shanghai Office'
gitlab_rails['auto_migrate'] = false
geo_secondary['auto_migrate'] = false
## turn off everything but the DB
sidekiq['enable']=false
puma['enable']=false
gitlab_workhorse['enable']=false
nginx['enable']=false
geo_logcursor['enable']=false
grafana['enable']=false
gitaly['enable']=false
redis['enable']=false
prometheus_monitoring['enable'] = false
## Configure the DBs for network
postgresql['enable'] = true
postgresql['listen_address'] = '0.0.0.0'
postgresql['sql_user_password'] = 'gitlab_user_password_hash'
# !! CAUTION !!
# This list of CIDR addresses should be customized
# - secondary application deployment
# - secondary database node(s)
postgresql['md5_auth_cidr_addresses'] = ['0.0.0.0/0']
geo_postgresql['listen_address'] = '0.0.0.0'
geo_postgresql['sql_user_password'] = 'gitlab_geo_user_password_hash'
# !! CAUTION !!
# This list of CIDR addresses should be customized
# - secondary application deployment
# - secondary database node(s)
geo_postgresql['md5_auth_cidr_addresses'] = ['0.0.0.0/0']
gitlab_rails['db_password']='gitlab_user_password'

We must replace several items:

• 
  gitlab_rails['geo_node_name'] must be replaced with a unique name for your site. See the Name field in
  Common settings.
• 
  gitlab_user_password_hash must be replaced with the hashed form of the
  gitlab password.
• 
  postgresql['md5_auth_cidr_addresses'] should be updated to be a list of
  explicit IP addresses, or address blocks in CIDR notation.
• 
  gitlab_geo_user_password_hash must be replaced with the hashed form of the
  gitlab_geo password.
• 
  geo_postgresql['md5_auth_cidr_addresses'] should be updated to be a list of
  explicit IP addresses, or address blocks in CIDR notation.
• 
  gitlab_user_password must be updated, and is used here to allow Omnibus GitLab
  to automate the PostgreSQL configuration.

The md5_auth_cidr_addresses should be in the form of
[ '127.0.0.1/24', '10.41.0.0/16'] . It is important to include 127.0.0.1 in
this list, as the automation in Omnibus GitLab connects using this. The
addresses in this list should include the IP addresses of all nodes of your
Secondary Kubernetes cluster. This can be left as ['0.0.0.0/0'] , however
it is not best practice .

After configuration above is prepared:

1. 
   

   Check TCP connectivity to the primary site’s PostgreSQL node:

   
   

   openssl s_client -connect <primary_node_ip>:5432 </dev/null
   

   The output should show the following:

   
   

   CONNECTED(00000003)
   write:errno=0
   

   
   

   If this step fails, you may be using the wrong IP address, or a firewall may
   be preventing access to the server. Check the IP address, paying close
   attention to the difference between public and private addresses and ensure
   that, if a firewall is present, the secondary PostgreSQL node is
   permitted to connect to the primary PostgreSQL node on TCP port 5432.
2. Place the content into /etc/gitlab/gitlab.rb
   
3. Run gitlab-ctl reconfigure . If you experience any issues in regards to the
   service not listening on TCP, try directly restarting it with
   gitlab-ctl restart postgresql .
4. Place the Primary PostgreSQL node’s certificate content from above into primary.crt
   
5. 
   

   Set up PostgreSQL TLS verification on the secondary PostgreSQL node:

   Install the primary.crt file:

   
   

   install \
      -D \
      -o gitlab-psql \
      -g gitlab-psql \
      -m 0400 \
      -T primary.crt ~gitlab-psql/.postgresql/root.crt
   

   PostgreSQL will now only recognize that exact certificate when verifying TLS
   connections. The certificate can only be replicated by someone with access
   to the private key, which is only present on the primary PostgreSQL
   node.

6. 
   

   Test that the gitlab-psql user can connect to the primary site’s PostgreSQL
   (the default Omnibus database name is gitlabhq_production ):

   
   

   sudo \
      -u gitlab-psql /opt/gitlab/embedded/bin/psql \
      --list \
      -U gitlab_replicator \
      -d "dbname=gitlabhq_production sslmode=verify-ca" \
      -W \
      -h <primary_database_node_ip>
   

   When prompted enter the password collected earlier for the
   gitlab_replicator user. If all worked correctly, you should see
   the list of primary PostgreSQL node’s databases.

   A failure to connect here indicates that the TLS configuration is incorrect.
   Ensure that the contents of ~gitlab-psql/data/server.crt on the
   primary PostgreSQL node
   match the contents of ~gitlab-psql/.postgresql/root.crt on the
   secondary PostgreSQL node.

7. 
   

   Replicate the databases. Replace PRIMARY_DATABASE_HOST with the IP or hostname
   of your Primary PostgreSQL node:

   
   

   gitlab-ctl replicate-geo-database --slot-name=geo_2 --host=PRIMARY_DATABASE_HOST --sslmode=verify-ca
   

8. 
   

   After replication has finished, we must reconfigure the Omnibus GitLab one last time
   to ensure pg_hba.conf is correct for the secondary PostgreSQL node:

   
   

   gitlab-ctl reconfigure
   

Copy secrets from the primary site to the secondary site

Now copy a few secrets from the Primary site’s Kubernetes deployment to the
Secondary site’s Kubernetes deployment:

• gitlab-geo-gitlab-shell-host-keys
• gitlab-geo-rails-secret
• 
  gitlab-geo-registry-secret , if Registry replication is enabled.

1. Change your kubectl context to that of your Primary.
2. 
   

   Collect these secrets from the Primary deployment:

   
   

   kubectl get --namespace gitlab -o yaml secret gitlab-geo-gitlab-shell-host-keys > ssh-host-keys.yaml
   kubectl get --namespace gitlab -o yaml secret gitlab-geo-rails-secret > rails-secrets.yaml
   kubectl get --namespace gitlab -o yaml secret gitlab-geo-registry-secret > registry-secrets.yaml
   

3. Change your kubectl context to that of your Secondary.
4. 
   

   Apply these secrets:

   
   

   kubectl --namespace gitlab apply -f ssh-host-keys.yaml
   kubectl --namespace gitlab apply -f rails-secrets.yaml
   kubectl --namespace gitlab apply -f registry-secrets.yaml
   

Next create a secret containing the database passwords. Replace the
passwords below with the appropriate values:

kubectl --namespace gitlab create secret generic geo \
   --from-literal=postgresql-password=gitlab_user_password \
   --from-literal=geo-postgresql-password=gitlab_geo_user_password

Deploy chart as Geo Secondary site

This section is performed on the Secondary site’s Kubernetes cluster.

To deploy this chart as a Geo Secondary site, start from this example configuration.

1. 
   

   Create a secondary.yaml file based on the example configuration
   and update the configuration to reflect the correct values:

   
   

   ## Geo Secondary
   global:
     # See docs.gitlab.com/charts/charts/globals
     # Configure host & domain
     hosts:
       hostSuffix: secondary
       domain: example.com
     # configure DB connection
     psql:
       host: geo-2.db.example.com
       port: 5432
       password:
         secret: geo
         key: postgresql-password
     # configure geo (secondary)
     geo:
       enabled: true
       role: secondary
       nodeName: Shanghai Office
       psql:
         host: geo-2.db.example.com
         port: 5431
         password:
           secret: geo
           key: geo-postgresql-password
   # External DB, disable
   postgresql:
     install: false
   

   
   
   • global.hosts.domain
   • global.psql.host
   • global.geo.psql.host
   • global.geo.nodeName must match
     the Name field of a Geo site in the Admin Area
     
   • Also configure any additional settings, such as:
     
     
     
     • Configuring SSL/TLS
     • Using external Redis
     • using external Object Storage
   • For external databases, global.psql.host is the secondary, read-only replica database, while global.geo.psql.host is the Geo tracking database
     
2. 
   

   Deploy the chart using this configuration:

   
   

   helm upgrade --install gitlab-geo gitlab/gitlab --namespace gitlab -f secondary.yaml
   

3. 
   

   Wait for the deployment to complete, and the application to come online.

Add Secondary Geo site via Primary

Now that both databases are configured and applications are deployed, we must tell
the Primary site that the Secondary site exists:

1. Visit the primary site, and on the top bar, select
   Main menu > Admin .
2. On the left sidebar, select Geo .
3. Select Add site .
4. Add the secondary site. Use the full GitLab URL for the URL.
5. Enter a Name with the global.geo.nodeName of the Secondary site. These values must always match exactly, character for character.
6. Enter Internal URL, for example https://shanghai.gitlab.example.com .
7. Optionally, choose which groups or storage shards should be replicated by the
   secondary site. Leave blank to replicate all.
8. Select Add node .

After the secondary site is added to the administration panel, it automatically starts
replicating missing data from the primary site. This process is known as “backfill”.
Meanwhile, the primary site starts to notify each secondary site of any changes, so
that the secondary site can replicate those changes promptly.

Confirm Operational Status

The final step is to double check the Geo configuration on the secondary site once fully
configured, via the Toolbox Pod.

1. 
   

   Find the Toolbox Pod:

   
   

   kubectl --namespace gitlab get pods -lapp=toolbox
   

2. 
   

   Attach to the Pod with kubectl exec :

   
   

   kubectl --namespace gitlab exec -ti gitlab-geo-toolbox-XXX -- bash -l
   

3. 
   

   Check the status of Geo configuration:

   
   

   gitlab-rake gitlab:geo:check
   

   You should see output similar to below:

   
   

   WARNING: This version of GitLab depends on gitlab-shell 10.2.0, but you're running Unknown. Please update gitlab-shell.
   Checking Geo ...
   
   GitLab Geo is available ... yes
   GitLab Geo is enabled ... yes
   GitLab Geo secondary database is correctly configured ... yes
   Database replication enabled? ... yes
   Database replication working? ... yes
   GitLab Geo HTTP(S) connectivity ...
   * Can connect to the primary node ... yes
   HTTP/HTTPS repository cloning is enabled ... yes
   Machine clock is synchronized ... Exception: getaddrinfo: Servname not supported for ai_socktype
   Git user has default SSH configuration? ... yes
   OpenSSH configured to use AuthorizedKeysCommand ... no
     Reason:
     Cannot find OpenSSH configuration file at: /assets/sshd_config
     Try fixing it:
     If you are not using our official docker containers,
     make sure you have OpenSSH server installed and configured correctly on this system
     For more information see:
     doc/administration/operations/fast_ssh_key_lookup.md
   GitLab configured to disable writing to authorized_keys file ... yes
   GitLab configured to store new projects in hashed storage? ... yes
   All projects are in hashed storage? ... yes
   
   Checking Geo ... Finished
   

   
   
   • Don’t worry about Exception: getaddrinfo: Servname not supported for ai_socktype ,
     as Kubernetes containers do not have access to the host clock. This is OK .
   • 
     OpenSSH configured to use AuthorizedKeysCommand ... no is expected . This
     Rake task is checking for a local SSH server, which is actually present in the
     gitlab-shell chart, deployed elsewhere, and already configured appropriately.