debian-mirror-gitlab/doc/administration/geo/secondary_proxy/index.md
2021-12-11 22:18:48 +05:30

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---
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/#assignments
type: howto
---
# Geo proxying for secondary sites **(PREMIUM SELF)**
> [Introduced](https://gitlab.com/groups/gitlab-org/-/epics/5914) in GitLab 14.4 [with a flag](../../feature_flags.md) named `geo_secondary_proxy`. Disabled by default.
FLAG:
On self-managed GitLab, by default this feature is not available. See below to [Set up a unified URL for Geo sites](#set-up-a-unified-url-for-geo-sites).
The feature is not ready for production use.
Use Geo proxying to:
- Have secondary sites serve read-write traffic by proxying to the primary site.
- Selectively accelerate replicated data types by directing read-only operations to the local site instead.
When enabled, users of the secondary site can use the WebUI as if they were accessing the
primary site's UI. This significantly improves the overall user experience of secondary sites.
With secondary proxying, web requests to secondary Geo sites are
proxied directly to the primary, and appear to act as a read-write site.
Proxying is done by the [`gitlab-workhorse`](https://gitlab.com/gitlab-org/gitlab-workhorse) component.
Traffic usually sent to the Rails application on the Geo secondary site is proxied
to the [internal URL](../index.md#internal-url) of the primary Geo site instead.
Use secondary proxying for use-cases including:
- Having all Geo sites behind a single URL.
- Geographically load-balancing traffic without worrying about write access.
## Set up a unified URL for Geo sites
Secondary sites can transparently serve read-write traffic. You can
use a single external URL so that requests can hit either the primary Geo site
or any secondary Geo sites that use Geo proxying.
### Configure an external URL to send traffic to both sites
Follow the [Location-aware public URL](location_aware_external_url.md) steps to create
a single URL used by all Geo sites, including the primary.
### Update the Geo sites to use the same external URL
1. On your Geo sites, SSH **into each node running Rails (Puma, Sidekiq, Log-Cursor)
and change the `external_url` to that of the single URL:
```shell
sudo editor /etc/gitlab/gitlab.rb
```
1. Reconfigure the updated nodes for the change to take effect if the URL was different than the one already set:
```shell
gitlab-ctl reconfigure
```
1. To match the new external URL set on the secondary Geo sites, the primary database
needs to reflect this change.
In the Geo administration page of the **primary** site, edit each Geo secondary that
is using the secondary proxying and set the `URL` field to the single URL.
Make sure the primary site is also using this URL.
### Enable secondary proxying
1. SSH into each application node (serving user traffic directly) on your secondary Geo site
and add the following environment variable:
```shell
sudo editor /etc/gitlab/gitlab.rb
```
```ruby
gitlab_workhorse['env'] = {
"GEO_SECONDARY_PROXY" => "1"
}
```
1. Reconfigure the updated nodes for the change to take effect:
```shell
gitlab-ctl reconfigure
```
1. SSH into one node running Rails on your primary Geo site and enable the Geo secondary proxy feature flag:
```shell
sudo gitlab-rails runner "Feature.enable(:geo_secondary_proxy)"
```
## Enable Geo proxying with Separate URLs
The ability to use proxying with separate URLs is still in development. You can follow the
["Geo secondary proxying with separate URLs" epic](https://gitlab.com/groups/gitlab-org/-/epics/6865)
for progress.
## Features accelerated by secondary Geo sites
Most HTTP traffic sent to a secondary Geo site can be proxied to the primary Geo site. With this architecture,
secondary Geo sites are able to support write requests. Certain **read** requests are handled locally by secondary
sites for improved latency and bandwidth nearby. All write requests are proxied to the primary site.
The following table details the components currently tested through the Geo secondary site Workhorse proxy.
It does not cover all data types, more will be added in the future as they are tested.
| Feature / component | Accelerated reads? |
|:----------------------------------------------------|:-----------------------|
| Project, wiki, design repository (using the web UI) | **{dotted-circle}** No |
| Project, wiki repository (using Git) | **{check-circle}** Yes <sup>1</sup> |
| Project, Personal Snippet (using the web UI) | **{dotted-circle}** No |
| Project, Personal Snippet (using Git) | **{check-circle}** Yes <sup>1</sup> |
| Group wiki repository (using the web UI) | **{dotted-circle}** No |
| Group wiki repository (using Git) | **{check-circle}** Yes <sup>1</sup> |
| User uploads | **{dotted-circle}** No |
| LFS objects (using the web UI) | **{dotted-circle}** No |
| LFS objects (using Git) | **{check-circle}** Yes |
| Pages | **{dotted-circle}** No <sup>2</sup> |
| Advanced search (using the web UI) | **{dotted-circle}** No |
1. Git reads are served from the local secondary while pushes get proxied to the primary.
Selective sync or cases where repositories don't exist locally on the Geo secondary throw a "not found" error.
1. Pages can use the same URL (without access control), but must be configured separately and are not proxied.