--- stage: Enablement group: Geo info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#designated-technical-writers type: howto --- # Disaster Recovery (Geo) **(PREMIUM ONLY)** Geo replicates your database, your Git repositories, and few other assets. We will support and replicate more data in the future, that will enable you to failover with minimal effort, in a disaster situation. See [Geo limitations](../index.md#limitations) for more information. CAUTION: **Warning:** Disaster recovery for multi-secondary configurations is in **Alpha**. For the latest updates, check the [Disaster Recovery epic for complete maturity](https://gitlab.com/groups/gitlab-org/-/epics/590). Multi-secondary configurations require the complete re-synchronization and re-configuration of all non-promoted secondaries and will cause downtime. ## Promoting a **secondary** Geo node in single-secondary configurations We don't currently provide an automated way to promote a Geo replica and do a failover, but you can do it manually if you have `root` access to the machine. This process promotes a **secondary** Geo node to a **primary** node. To regain geographic redundancy as quickly as possible, you should add a new **secondary** node immediately after following these instructions. ### Step 1. Allow replication to finish if possible If the **secondary** node is still replicating data from the **primary** node, follow [the planned failover docs](planned_failover.md) as closely as possible in order to avoid unnecessary data loss. ### Step 2. Permanently disable the **primary** node CAUTION: **Warning:** If the **primary** node goes offline, there may be data saved on the **primary** node that has not been replicated to the **secondary** node. This data should be treated as lost if you proceed. If an outage on the **primary** node happens, you should do everything possible to avoid a split-brain situation where writes can occur in two different GitLab instances, complicating recovery efforts. So to prepare for the failover, we must disable the **primary** node. 1. SSH into the **primary** node to stop and disable GitLab, if possible: ```shell sudo gitlab-ctl stop ``` Prevent GitLab from starting up again if the server unexpectedly reboots: ```shell sudo systemctl disable gitlab-runsvdir ``` NOTE: **Note:** (**CentOS only**) In CentOS 6 or older, there is no easy way to prevent GitLab from being started if the machine reboots isn't available (see [Omnibus GitLab issue #3058](https://gitlab.com/gitlab-org/omnibus-gitlab/-/issues/3058)). It may be safest to uninstall the GitLab package completely: ```shell yum remove gitlab-ee ``` NOTE: **Note:** (**Ubuntu 14.04 LTS**) If you are using an older version of Ubuntu or any other distribution based on the Upstart init system, you can prevent GitLab from starting if the machine reboots by doing the following: ```shell initctl stop gitlab-runsvvdir echo 'manual' > /etc/init/gitlab-runsvdir.override initctl reload-configuration ``` 1. If you do not have SSH access to the **primary** node, take the machine offline and prevent it from rebooting by any means at your disposal. Since there are many ways you may prefer to accomplish this, we will avoid a single recommendation. You may need to: - Reconfigure the load balancers. - Change DNS records (for example, point the primary DNS record to the **secondary** node to stop usage of the **primary** node). - Stop the virtual servers. - Block traffic through a firewall. - Revoke object storage permissions from the **primary** node. - Physically disconnect a machine. 1. If you plan to [update the primary domain DNS record](#step-4-optional-updating-the-primary-domain-dns-record), you may wish to lower the TTL now to speed up propagation. ### Step 3. Promoting a **secondary** node Note the following when promoting a secondary: - If replication was paused on the secondary node (for example as a part of upgrading, while you were running a version of GitLab earlier than 13.4), you _must_ [enable the node by using the database](../replication/troubleshooting.md#message-activerecordrecordinvalid-validation-failed-enabled-geo-primary-node-cannot-be-disabled) before proceeding. - A new **secondary** should not be added at this time. If you want to add a new **secondary**, do this after you have completed the entire process of promoting the **secondary** to the **primary**. - If you encounter an `ActiveRecord::RecordInvalid: Validation failed: Name has already been taken` error message during this process, for more information, see this [troubleshooting advice](../replication/troubleshooting.md#fixing-errors-during-a-failover-or-when-promoting-a-secondary-to-a-primary-node). #### Promoting a **secondary** node running on a single machine 1. SSH in to your **secondary** node and login as root: ```shell sudo -i ``` 1. Edit `/etc/gitlab/gitlab.rb` to reflect its new status as **primary** by removing any lines that enabled the `geo_secondary_role`: Users of GitLab 13.5 or later can skip this step, due to the appropriate roles being enabled or disabled during the promotion in the following step. ```ruby ## In pre-11.5 documentation, the role was enabled as follows. Remove this line. geo_secondary_role['enable'] = true ## In 11.5+ documentation, the role was enabled as follows. Remove this line. roles ['geo_secondary_role'] ``` 1. Promote the **secondary** node to the **primary** node. CAUTION: **Caution:** If the secondary node [has been paused](../../geo/index.md#pausing-and-resuming-replication), this performs a point-in-time recovery to the last known state. Data that was created on the primary while the secondary was paused will be lost. To promote the secondary node to primary along with preflight checks: ```shell gitlab-ctl promote-to-primary-node ``` If you have already run the [preflight checks](planned_failover.md#preflight-checks) separately or don't want to run them, you can skip preflight checks with: ```shell gitlab-ctl promote-to-primary-node --skip-preflight-checks ``` You can also promote the secondary node to primary **without any further confirmation**, even when preflight checks fail: ```shell gitlab-ctl promote-to-primary-node --force ``` 1. Verify you can connect to the newly promoted **primary** node using the URL used previously for the **secondary** node. 1. If successful, the **secondary** node has now been promoted to the **primary** node. #### Promoting a **secondary** node with multiple servers The `gitlab-ctl promote-to-primary-node` command cannot be used yet in conjunction with multiple servers, as it can only perform changes on a **secondary** with only a single machine. Instead, you must do this manually. CAUTION: **Caution:** If the secondary node [has been paused](../../geo/index.md#pausing-and-resuming-replication), this performs a point-in-time recovery to the last known state. Data that was created on the primary while the secondary was paused will be lost. 1. SSH in to the database node in the **secondary** and trigger PostgreSQL to promote to read-write: ```shell sudo gitlab-ctl promote-db ``` In GitLab 12.8 and earlier, see [Message: `sudo: gitlab-pg-ctl: command not found`](../replication/troubleshooting.md#message-sudo-gitlab-pg-ctl-command-not-found). 1. Edit `/etc/gitlab/gitlab.rb` on every machine in the **secondary** to reflect its new status as **primary** by removing any lines that enabled the `geo_secondary_role`: ```ruby ## In pre-11.5 documentation, the role was enabled as follows. Remove this line. geo_secondary_role['enable'] = true ## In 11.5+ documentation, the role was enabled as follows. Remove this line. roles ['geo_secondary_role'] ``` After making these changes [Reconfigure GitLab](../../restart_gitlab.md#omnibus-gitlab-reconfigure) each machine so the changes take effect. 1. Promote the **secondary** to **primary**. SSH into a single application server and execute: ```shell sudo gitlab-rake geo:set_secondary_as_primary ``` 1. Verify you can connect to the newly promoted **primary** using the URL used previously for the **secondary**. 1. Success! The **secondary** has now been promoted to **primary**. #### Promoting a **secondary** node with an external PostgreSQL database The `gitlab-ctl promote-to-primary-node` command cannot be used in conjunction with an external PostgreSQL database, as it can only perform changes on a **secondary** node with GitLab and the database on the same machine. As a result, a manual process is required: 1. Promote the replica database associated with the **secondary** site. This will set the database to read-write: - Amazon RDS - [Promoting a Read Replica to Be a Standalone DB Instance](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_ReadRepl.html#USER_ReadRepl.Promote) - Azure Database for PostgreSQL - [Stop replication](https://docs.microsoft.com/en-us/azure/postgresql/howto-read-replicas-portal#stop-replication) - Other external PostgreSQL databases - save the script below in you secondary node, for example `/tmp/geo_promote.sh`, and modify the connection parameters to match your environment. Then, execute it to promote the replica: ```shell #!/bin/bash PG_SUPERUSER=postgres # The path to your pg_ctl binary. You may need to adjust this path to match # your PostgreSQL installation PG_CTL_BINARY=/usr/lib/postgresql/10/bin/pg_ctl # The path to your PostgreSQL data directory. You may need to adjust this # path to match your PostgreSQL installation. You can also run # `SHOW data_directory;` from PostgreSQL to find your data directory PG_DATA_DIRECTORY=/etc/postgresql/10/main # Promote the PostgreSQL database and allow read/write operations sudo -u $PG_SUPERUSER $PG_CTL_BINARY -D $PG_DATA_DIRECTORY promote ``` 1. Edit `/etc/gitlab/gitlab.rb` on every node in the **secondary** site to reflect its new status as **primary** by removing any lines that enabled the `geo_secondary_role`: ```ruby ## In GitLab 11.4 and earlier, remove this line. geo_secondary_role['enable'] = true ## In GitLab 11.5 and later, remove this line. roles ['geo_secondary_role'] ``` After making these changes [Reconfigure GitLab](../../restart_gitlab.md#omnibus-gitlab-reconfigure) on each node so the changes take effect. 1. Promote the **secondary** to **primary**. SSH into a single secondary application node and execute: ```shell sudo gitlab-rake geo:set_secondary_as_primary ``` 1. Verify you can connect to the newly promoted **primary** site using the URL used previously for the **secondary** site. Success! The **secondary** site has now been promoted to **primary**. ### Step 4. (Optional) Updating the primary domain DNS record Updating the DNS records for the primary domain to point to the **secondary** node will prevent the need to update all references to the primary domain to the secondary domain, like changing Git remotes and API URLs. 1. SSH into the **secondary** node and login as root: ```shell sudo -i ``` 1. Update the primary domain's DNS record. After updating the primary domain's DNS records to point to the **secondary** node, edit `/etc/gitlab/gitlab.rb` on the **secondary** node to reflect the new URL: ```ruby # Change the existing external_url configuration external_url 'https://' ``` NOTE: **Note:** Changing `external_url` won't prevent access via the old secondary URL, as long as the secondary DNS records are still intact. 1. Reconfigure the **secondary** node for the change to take effect: ```shell gitlab-ctl reconfigure ``` 1. Execute the command below to update the newly promoted **primary** node URL: ```shell gitlab-rake geo:update_primary_node_url ``` This command will use the changed `external_url` configuration defined in `/etc/gitlab/gitlab.rb`. 1. For GitLab 11.11 through 12.7 only, you may need to update the **primary** node's name in the database. This bug has been fixed in GitLab 12.8. To determine if you need to do this, search for the `gitlab_rails["geo_node_name"]` setting in your `/etc/gitlab/gitlab.rb` file. If it is commented out with `#` or not found at all, then you will need to update the **primary** node's name in the database. You can search for it like so: ```shell grep "geo_node_name" /etc/gitlab/gitlab.rb ``` To update the **primary** node's name in the database: ```shell gitlab-rails runner 'Gitlab::Geo.primary_node.update!(name: GeoNode.current_node_name)' ``` 1. Verify you can connect to the newly promoted **primary** using its URL. If you updated the DNS records for the primary domain, these changes may not have yet propagated depending on the previous DNS records TTL. ### Step 5. (Optional) Add **secondary** Geo node to a promoted **primary** node Promoting a **secondary** node to **primary** node using the process above does not enable Geo on the new **primary** node. To bring a new **secondary** node online, follow the [Geo setup instructions](../index.md#setup-instructions). ### Step 6. (Optional) Removing the secondary's tracking database Every **secondary** has a special tracking database that is used to save the status of the synchronization of all the items from the **primary**. Because the **secondary** is already promoted, that data in the tracking database is no longer required. The data can be removed with the following command: ```shell sudo rm -rf /var/opt/gitlab/geo-postgresql ``` If you have any `geo_secondary[]` configuration options enabled in your `gitlab.rb` file, these can be safely commented out or removed, and then [reconfigure GitLab](../../restart_gitlab.md#omnibus-gitlab-reconfigure) for the changes to take effect. ## Promoting secondary Geo replica in multi-secondary configurations If you have more than one **secondary** node and you need to promote one of them, we suggest you follow [Promoting a **secondary** Geo node in single-secondary configurations](#promoting-a-secondary-geo-node-in-single-secondary-configurations) and after that you also need two extra steps. ### Step 1. Prepare the new **primary** node to serve one or more **secondary** nodes 1. SSH into the new **primary** node and login as root: ```shell sudo -i ``` 1. Edit `/etc/gitlab/gitlab.rb` ```ruby ## Enable a Geo Primary role (if you haven't yet) roles ['geo_primary_role'] ## # Allow PostgreSQL client authentication from the primary and secondary IPs. These IPs may be # public or VPC addresses in CIDR format, for example ['198.51.100.1/32', '198.51.100.2/32'] ## postgresql['md5_auth_cidr_addresses'] = ['/32', '/32'] # Every secondary server needs to have its own slot so specify the number of secondary nodes you're going to have postgresql['max_replication_slots'] = 1 ## ## Disable automatic database migrations temporarily ## (until PostgreSQL is restarted and listening on the private address). ## gitlab_rails['auto_migrate'] = false ``` (For more details about these settings you can read [Configure the primary server](../setup/database.md#step-1-configure-the-primary-server)) 1. Save the file and reconfigure GitLab for the database listen changes and the replication slot changes to be applied. ```shell gitlab-ctl reconfigure ``` Restart PostgreSQL for its changes to take effect: ```shell gitlab-ctl restart postgresql ``` 1. Re-enable migrations now that PostgreSQL is restarted and listening on the private address. Edit `/etc/gitlab/gitlab.rb` and **change** the configuration to `true`: ```ruby gitlab_rails['auto_migrate'] = true ``` Save the file and reconfigure GitLab: ```shell gitlab-ctl reconfigure ``` ### Step 2. Initiate the replication process Now we need to make each **secondary** node listen to changes on the new **primary** node. To do that you need to [initiate the replication process](../setup/database.md#step-3-initiate-the-replication-process) again but this time for another **primary** node. All the old replication settings will be overwritten. ## Troubleshooting This section was moved to [another location](../replication/troubleshooting.md#fixing-errors-during-a-failover-or-when-promoting-a-secondary-to-a-primary-node).