--- 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