diff options
Diffstat (limited to 'doc/administration/geo/replication/index.md')
-rw-r--r-- | doc/administration/geo/replication/index.md | 315 |
1 files changed, 2 insertions, 313 deletions
diff --git a/doc/administration/geo/replication/index.md b/doc/administration/geo/replication/index.md index f1cc9f0df8b..5e9dd73ecc5 100644 --- a/doc/administration/geo/replication/index.md +++ b/doc/administration/geo/replication/index.md @@ -1,316 +1,5 @@ --- -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 +redirect_to: '../index.md' --- -# Replication (Geo) **(PREMIUM ONLY)** - -> - Introduced in GitLab Enterprise Edition 8.9. -> - Using Geo in combination with -> [multi-node architectures](../../reference_architectures/index.md) -> is considered **Generally Available** (GA) in -> [GitLab Premium](https://about.gitlab.com/pricing/) 10.4. - -Replication with Geo is the solution for widely distributed development teams. - -## Overview - -Fetching large repositories can take a long time for teams located far from a single GitLab instance. - -Geo provides local, read-only instances of your GitLab instances. This can reduce the time it takes -to clone and fetch large repositories, speeding up development. - -NOTE: **Note:** -Check the [requirements](#requirements-for-running-geo) carefully before setting up Geo. - -For a video introduction to Geo, see [Introduction to GitLab Geo - GitLab Features](https://www.youtube.com/watch?v=-HDLxSjEh6w). - -CAUTION: **Caution:** -Geo undergoes significant changes from release to release. Upgrades **are** supported and [documented](#updating-geo), but you should ensure that you're using the right version of the documentation for your installation. - -To make sure you're using the right version of the documentation, navigate to [the source version of this page on GitLab.com](https://gitlab.com/gitlab-org/gitlab/blob/master/doc/administration/geo/replication/index.md) and choose the appropriate release from the **Switch branch/tag** dropdown. For example, [`v11.2.3-ee`](https://gitlab.com/gitlab-org/gitlab/blob/v11.2.3-ee/doc/administration/geo/replication/index.md). - -## Use cases - -Implementing Geo provides the following benefits: - -- Reduce from minutes to seconds the time taken for your distributed developers to clone and fetch large repositories and projects. -- Enable all of your developers to contribute ideas and work in parallel, no matter where they are. -- Balance the read-only load between your **primary** and **secondary** nodes. - -In addition, it: - -- Can be used for cloning and fetching projects, in addition to reading any data available in the GitLab web interface (see [current limitations](#current-limitations)). -- Overcomes slow connections between distant offices, saving time by improving speed for distributed teams. -- Helps reducing the loading time for automated tasks, custom integrations, and internal workflows. -- Can quickly fail over to a **secondary** node in a [disaster recovery](../disaster_recovery/index.md) scenario. -- Allows [planned failover](../disaster_recovery/planned_failover.md) to a **secondary** node. - -Geo provides: - -- Read-only **secondary** nodes: Maintain one **primary** GitLab node while still enabling read-only **secondary** nodes for each of your distributed teams. -- Authentication system hooks: **Secondary** nodes receives all authentication data (like user accounts and logins) from the **primary** instance. -- An intuitive UI: **Secondary** nodes utilize the same web interface your team has grown accustomed to. In addition, there are visual notifications that block write operations and make it clear that a user is on a **secondary** node. - -## How it works - -Your Geo instance can be used for cloning and fetching projects, in addition to reading any data. This will make working with large repositories over large distances much faster. - -![Geo overview](img/geo_overview.png) - -When Geo is enabled, the: - -- Original instance is known as the **primary** node. -- Replicated read-only nodes are known as **secondary** nodes. - -Keep in mind that: - -- **Secondary** nodes talk to the **primary** node to: - - Get user data for logins (API). - - Replicate repositories, LFS Objects, and Attachments (HTTPS + JWT). -- Since GitLab Premium 10.0, the **primary** node no longer talks to **secondary** nodes to notify for changes (API). -- Pushing directly to a **secondary** node (for both HTTP and SSH, including Git LFS) was [introduced](https://about.gitlab.com/releases/2018/09/22/gitlab-11-3-released/) in [GitLab Premium](https://about.gitlab.com/pricing/#self-managed) 11.3. -- There are [limitations](#current-limitations) in the current implementation. - -### Architecture - -The following diagram illustrates the underlying architecture of Geo. - -![Geo architecture](img/geo_architecture.png) - -In this diagram: - -- There is the **primary** node and the details of one **secondary** node. -- Writes to the database can only be performed on the **primary** node. A **secondary** node receives database - updates via PostgreSQL streaming replication. -- If present, the [LDAP server](#ldap) should be configured to replicate for [Disaster Recovery](../disaster_recovery/index.md) scenarios. -- A **secondary** node performs different type of synchronizations against the **primary** node, using a special - authorization protected by JWT: - - Repositories are cloned/updated via Git over HTTPS. - - Attachments, LFS objects, and other files are downloaded via HTTPS using a private API endpoint. - -From the perspective of a user performing Git operations: - -- The **primary** node behaves as a full read-write GitLab instance. -- **Secondary** nodes are read-only but proxy Git push operations to the **primary** node. This makes **secondary** nodes appear to support push operations themselves. - -To simplify the diagram, some necessary components are omitted. Note that: - -- Git over SSH requires [`gitlab-shell`](https://gitlab.com/gitlab-org/gitlab-shell) and OpenSSH. -- Git over HTTPS required [`gitlab-workhorse`](https://gitlab.com/gitlab-org/gitlab-workhorse). - -Note that a **secondary** node needs two different PostgreSQL databases: - -- A read-only database instance that streams data from the main GitLab database. -- [Another database instance](#geo-tracking-database) used internally by the **secondary** node to record what data has been replicated. - -In **secondary** nodes, there is an additional daemon: [Geo Log Cursor](#geo-log-cursor). - -## Requirements for running Geo - -The following are required to run Geo: - -- An operating system that supports OpenSSH 6.9+ (needed for - [fast lookup of authorized SSH keys in the database](../../operations/fast_ssh_key_lookup.md)) - The following operating systems are known to ship with a current version of OpenSSH: - - [CentOS](https://www.centos.org) 7.4+ - - [Ubuntu](https://ubuntu.com) 16.04+ -- PostgreSQL 11+ with [Streaming Replication](https://wiki.postgresql.org/wiki/Streaming_Replication) -- Git 2.9+ -- All nodes must run the same GitLab version. - -Additionally, check GitLab's [minimum requirements](../../../install/requirements.md), -and we recommend you use: - -- At least GitLab Enterprise Edition 10.0 for basic Geo features. -- The latest version for a better experience. - -### Firewall rules - -The following table lists basic ports that must be open between the **primary** and **secondary** nodes for Geo. - -| **Primary** node | **Secondary** node | Protocol | -|:-----------------|:-------------------|:-------------| -| 80 | 80 | HTTP | -| 443 | 443 | TCP or HTTPS | -| 22 | 22 | TCP | -| 5432 | | PostgreSQL | - -See the full list of ports used by GitLab in [Package defaults](https://docs.gitlab.com/omnibus/package-information/defaults.html) - -NOTE: **Note:** -[Web terminal](../../../ci/environments/index.md#web-terminals) support requires your load balancer to correctly handle WebSocket connections. -When using HTTP or HTTPS proxying, your load balancer must be configured to pass through the `Connection` and `Upgrade` hop-by-hop headers. See the [web terminal](../../integration/terminal.md) integration guide for more details. - -NOTE: **Note:** -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. - -### LDAP - -We recommend that if you use LDAP on your **primary** node, you also set up secondary LDAP servers on each **secondary** node. Otherwise, users will not be able to perform Git operations over HTTP(s) on the **secondary** node using HTTP Basic Authentication. However, Git via SSH and personal access tokens will still work. - -NOTE: **Note:** -It is possible for all **secondary** nodes to share an LDAP server, but additional latency can be an issue. Also, consider what LDAP server will be available in a [disaster recovery](../disaster_recovery/index.md) scenario if a **secondary** node is promoted to be a **primary** node. - -Check for instructions on how to set up replication in your LDAP service. Instructions will be different depending on the software or service used. For example, OpenLDAP provides [these instructions](https://www.openldap.org/doc/admin24/replication.html). - -### Geo Tracking Database - -The tracking database instance is used as metadata to control what needs to be updated on the disk of the local instance. For example: - -- Download new assets. -- Fetch new LFS Objects. -- Fetch changes from a repository that has recently been updated. - -Because the replicated database instance is read-only, we need this additional database instance for each **secondary** node. - -### Geo Log Cursor - -This daemon: - -- Reads a log of events replicated by the **primary** node to the **secondary** database instance. -- Updates the Geo Tracking Database instance with changes that need to be executed. - -When something is marked to be updated in the tracking database instance, asynchronous jobs running on the **secondary** node will execute the required operations and update the state. - -This new architecture allows GitLab to be resilient to connectivity issues between the nodes. It doesn't matter how long the **secondary** node is disconnected from the **primary** node as it will be able to replay all the events in the correct order and become synchronized with the **primary** node again. - -## Setup instructions - -These instructions assume you have a working instance of GitLab. They guide you through: - -1. Making your existing instance the **primary** node. -1. Adding **secondary** nodes. - -CAUTION: **Caution:** -The steps below should be followed in the order they appear. **Make sure the GitLab version is the same on all nodes.** - -### Using Omnibus GitLab - -If you installed GitLab using the Omnibus packages (highly recommended): - -1. [Install GitLab Enterprise Edition](https://about.gitlab.com/install/) on the server that will serve as the **secondary** node. Do not create an account or log in to the new **secondary** node. -1. [Upload the GitLab License](../../../user/admin_area/license.md) on the **primary** node to unlock Geo. The license must be for [GitLab Premium](https://about.gitlab.com/pricing/) or higher. -1. [Set up the database replication](database.md) (`primary (read-write) <-> secondary (read-only)` topology). -1. [Configure fast lookup of authorized SSH keys in the database](../../operations/fast_ssh_key_lookup.md). This step is required and needs to be done on **both** the **primary** and **secondary** nodes. -1. [Configure GitLab](configuration.md) to set the **primary** and **secondary** nodes. -1. Optional: [Configure a secondary LDAP server](../../auth/ldap/index.md) for the **secondary** node. See [notes on LDAP](#ldap). -1. [Follow the "Using a Geo Server" guide](using_a_geo_server.md). - -## Post-installation documentation - -After installing GitLab on the **secondary** nodes and performing the initial configuration, see the following documentation for post-installation information. - -### Configuring Geo - -For information on configuring Geo, see [Geo configuration](configuration.md). - -### Updating Geo - -For information on how to update your Geo nodes to the latest GitLab version, see [Updating the Geo nodes](updating_the_geo_nodes.md). - -### Pausing and resuming replication - -> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/35913) in [GitLab Premium](https://about.gitlab.com/pricing/) 13.2. - -In some circumstances, like during [upgrades](updating_the_geo_nodes.md) or a [planned failover](../disaster_recovery/planned_failover.md), it is desirable to pause replication between the primary and secondary. - -Pausing and resuming replication is done via a command line tool from the secondary node. - -**To Pause: (from secondary)** - -```shell -gitlab-ctl geo-replication-pause -``` - -**To Resume: (from secondary)** - -```shell -gitlab-ctl geo-replication-resume -``` - -### Configuring Geo for multiple nodes - -For information on configuring Geo for multiple nodes, see [Geo for multiple servers](multiple_servers.md). - -### Configuring Geo with Object Storage - -For information on configuring Geo with object storage, see [Geo with Object storage](object_storage.md). - -### Disaster Recovery - -For information on using Geo in disaster recovery situations to mitigate data-loss and restore services, see [Disaster Recovery](../disaster_recovery/index.md). - -### Replicating the Container Registry - -For more information on how to replicate the Container Registry, see [Docker Registry for a **secondary** node](docker_registry.md). - -### Security Review - -For more information on Geo security, see [Geo security review](security_review.md). - -### Tuning Geo - -For more information on tuning Geo, see [Tuning Geo](tuning.md). - -### Set up a location-aware Git URL - -For an example of how to set up a location-aware Git remote URL with AWS Route53, see [Location-aware Git remote URL with AWS Route53](location_aware_git_url.md). - -## Remove Geo node - -For more information on removing a Geo node, see [Removing **secondary** Geo nodes](remove_geo_node.md). - -## Disable Geo - -To find out how to disable Geo, see [Disabling Geo](disable_geo.md). - -## Current limitations - -CAUTION: **Caution:** -This list of limitations only reflects the latest version of GitLab. If you are using an older version, extra limitations may be in place. - -- Pushing directly to a **secondary** node redirects (for HTTP) or proxies (for SSH) the request to the **primary** node instead of [handling it directly](https://gitlab.com/gitlab-org/gitlab/-/issues/1381), except when using Git over HTTP with credentials embedded within the URI. For example, `https://user:password@secondary.tld`. -- Cloning, pulling, or pushing repositories that exist on the **primary** node but not on the **secondary** nodes where [selective synchronization](configuration.md#selective-synchronization) does not include the project is not supported over SSH [but support is planned](https://gitlab.com/groups/gitlab-org/-/epics/2562). HTTP(S) is supported. -- The **primary** node has to be online for OAuth login to happen. Existing sessions and Git are not affected. Support for the **secondary** node to use an OAuth provider independent from the primary is [being planned](https://gitlab.com/gitlab-org/gitlab/-/issues/208465). -- The installation takes multiple manual steps that together can take about an hour depending on circumstances. We are working on improving this experience. See [Omnibus GitLab issue #2978](https://gitlab.com/gitlab-org/omnibus-gitlab/-/issues/2978) for details. -- Real-time updates of issues/merge requests (for example, via long polling) doesn't work on the **secondary** node. -- [Selective synchronization](configuration.md#selective-synchronization) applies only to files and repositories. Other datasets are replicated to the **secondary** node in full, making it inappropriate for use as an access control mechanism. -- Object pools for forked project deduplication work only on the **primary** node, and are duplicated on the **secondary** node. -- [External merge request diffs](../../merge_request_diffs.md) will not be replicated if they are on-disk, and viewing merge requests will fail. However, external MR diffs in object storage **are** supported. The default configuration (in-database) does work. -- GitLab Runners cannot register with a **secondary** node. Support for this is [planned for the future](https://gitlab.com/gitlab-org/gitlab/-/issues/3294). - -### Limitations on replication/verification - -You can keep track of the progress to implement the missing items in -these epics/issues: - -- [Unreplicated Data Types](https://gitlab.com/groups/gitlab-org/-/epics/893) -- [Verify all replicated data](https://gitlab.com/groups/gitlab-org/-/epics/1430) - -There is a complete list of all GitLab [data types](datatypes.md) and [existing support for replication and verification](datatypes.md#limitations-on-replicationverification). - -## Frequently Asked Questions - -For answers to common questions, see the [Geo FAQ](faq.md). - -## Log files - -Since GitLab 9.5, Geo stores structured log messages in a `geo.log` file. For Omnibus installations, this file is at `/var/log/gitlab/gitlab-rails/geo.log`. - -This file contains information about when Geo attempts to sync repositories and files. Each line in the file contains a separate JSON entry that can be ingested into. For example, Elasticsearch or Splunk. - -For example: - -```json -{"severity":"INFO","time":"2017-08-06T05:40:16.104Z","message":"Repository update","project_id":1,"source":"repository","resync_repository":true,"resync_wiki":true,"class":"Gitlab::Geo::LogCursor::Daemon","cursor_delay_s":0.038} -``` - -This message shows that Geo detected that a repository update was needed for project `1`. - -## Troubleshooting - -For troubleshooting steps, see [Geo Troubleshooting](troubleshooting.md). +This document was moved to [another location](../index.md). |