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---
stage: Create
group: Source Code
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/product/ux/technical-writing/#assignments
---
# `gitlab-sshd` **(FREE SELF)**
> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/299109) in GitLab 14.5 as an **Alpha** release for self-managed customers.
> - Ready for production use with [Cloud Native GitLab in GitLab 15.1](https://gitlab.com/gitlab-org/charts/gitlab/-/issues/2540) and [Omnibus GitLab in GitLab 15.9](https://gitlab.com/gitlab-org/omnibus-gitlab/-/issues/5937).
`gitlab-sshd` is [a standalone SSH server](https://gitlab.com/gitlab-org/gitlab-shell/-/tree/main/internal/sshd)
written in Go. It is provided as a part of the `gitlab-shell` package. It has a lower memory
use as a OpenSSH alternative, and supports
[group access restriction by IP address](../../user/group/index.md) for applications
running behind the proxy.
`gitlab-sshd` is a lightweight alternative to OpenSSH for providing
[SSH operations](https://gitlab.com/gitlab-org/gitlab-shell/-/blob/71a7f34a476f778e62f8fe7a453d632d395eaf8f/doc/features.md).
While OpenSSH uses a restricted shell approach, `gitlab-sshd` behaves more like a
modern multi-threaded server application, responding to incoming requests. The major
difference is that OpenSSH uses SSH as a transport protocol while `gitlab-sshd` uses Remote Procedure Calls (RPCs). See [the blog post](https://about.gitlab.com/blog/2022/08/17/why-we-have-implemented-our-own-sshd-solution-on-gitlab-sass/) for more details.
The capabilities of GitLab Shell are not limited to Git operations.
If you are considering switching from OpenSSH to `gitlab-sshd`, consider these concerns:
- `gitlab-sshd` supports the PROXY protocol. It can run behind proxy servers that rely
on it, such as HAProxy. The PROXY protocol is not enabled by default, but [it can be enabled](#proxy-protocol-support).
- `gitlab-sshd` **does not** support SSH certificates. For more details, read
[issue #495](https://gitlab.com/gitlab-org/gitlab-shell/-/issues/495).
## Enable `gitlab-sshd`
To use `gitlab-sshd`:
::Tabs
:::TabTitle Linux package (Omnibus)
The following instructions enable `gitlab-sshd` on a different port than OpenSSH:
1. Edit `/etc/gitlab/gitlab.rb`:
```ruby
gitlab_sshd['enable'] = true
gitlab_sshd['listen_address'] = '[::]:2222' # Adjust the port accordingly
```
1. Optional. By default, Omnibus GitLab generates SSH host keys for `gitlab-sshd` if
they do not exist in `/var/opt/gitlab/gitlab-sshd`. If you wish to disable this automatic generation, add this line:
```ruby
gitlab_sshd['generate_host_keys'] = false
```
1. Save the file and reconfigure GitLab:
```shell
sudo gitlab-ctl reconfigure
```
By default, `gitlab-sshd` runs as the `git` user. As a result, `gitlab-sshd` cannot
run on privileged port numbers lower than 1024. This means users must
access Git with the `gitlab-sshd` port, or use a load balancer that
directs SSH traffic to the `gitlab-sshd` port to hide this.
Users may see host key warnings because the newly-generated host keys
differ from the OpenSSH host keys. Consider disabling host key
generation and copy the existing OpenSSH host keys into
`/var/opt/gitlab/gitlab-sshd` if this is an issue.
:::TabTitle Helm chart (Kubernetes)
The following instructions switch OpenSSH in favor of `gitlab-sshd`:
1. Set the `gitlab-shell` charts `sshDaemon` option to
[`gitlab-sshd`](https://docs.gitlab.com/charts/charts/gitlab/gitlab-shell/index.html#installation-command-line-options).
For example:
```yaml
gitlab:
gitlab-shell:
sshDaemon: gitlab-sshd
```
1. Perform a Helm upgrade.
By default, `gitlab-sshd` listens for:
- External requests on port 22 (`global.shell.port`).
- Internal requests on port 2222 (`gitlab.gitlab-shell.service.internalPort`).
You can [configure different ports in the Helm chart](https://docs.gitlab.com/charts/charts/gitlab/gitlab-shell/#configuration).
::EndTabs
## PROXY protocol support
When a load balancer is used in front of `gitlab-sshd`, GitLab reports the IP
address of the proxy instead of the actual IP address of the client. `gitlab-sshd`
supports the [PROXY protocol](https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt) to
obtain the real IP address.
::Tabs
:::TabTitle Linux package (Omnibus)
To enable the PROXY protocol:
1. Edit `/etc/gitlab/gitlab.rb`:
```ruby
gitlab_sshd['proxy_protocol'] = true
# # Proxy protocol policy ("use", "require", "reject", "ignore"), "use" is the default value
gitlab_sshd['proxy_policy'] = "use"
```
1. Save the file and reconfigure GitLab:
```shell
sudo gitlab-ctl reconfigure
```
:::TabTitle Helm chart (Kubernetes)
1. Set the [`gitlab.gitlab-shell.config` options](https://docs.gitlab.com/charts/charts/gitlab/gitlab-shell/index.html#installation-command-line-options). For example:
```yaml
gitlab:
gitlab-shell:
config:
proxyProtocol: true
proxyPolicy: "use"
```
1. Perform a Helm upgrade.
::EndTabs
|
