Configuring an SSH port other than 22 disables START_SSH_SERVER

[kalsan]

• Gitea version (or commit ref): 1.9.0+dev-415-g49ee9d277
• Git version: 2.20.1
• Operating system: Debian/docker
• Database (use [x]):
  • PostgreSQL
  • MySQL
  • MSSQL
  • SQLite
• Can you reproduce the bug at https://try.gitea.io:
  • Yes (provide example URL)
  • No
  • Not relevant
• Log gist: n/a

Description

Configuring an SSH port other than 22 disables START_SSH_SERVER. To reproduce, do:

• Get the docker-compose.yml for the minimal installation as recommended by the Gitea docs
• In the yml file, replace SSH port ("222:22") by 2222, i.e. sure the line reads "2222:2222" for the port forwarding
• docker-compose up, then go to localhost:3000 to be welcomed by the Gitea installation wizard
• Set the SSH port to 2222

Result: in app.ini, the option START_SSH_SERVER is omitted and thus, it is not possible to access Gittea via the proposed URL ssh://git@localhost:2222/user/repo.git as an attempt to do so will result in an exception "ssh_exchange_identification: Connection closed by remote host"

Expected result / how to fix: Adding the option START_SSH_SERVER = true to app.ini fixes the problem. The installer should do this even when the ssh port is not 22.

Note: Be sure to have a high enough port for trying this (e.g. when the port is set to 222, there is a permissions problem on Linux).

[lunny]

Could you paste your docker-compose file here?

[zeripath]

I suspect this is the problem that #7286 solves.

Oh actually I think I've misread this - I think this is a problem to do with the install page.

---

Ah no I didn't misread it!

So the docker by default provides an openSSH server - which listens on port 22. Changing the SSH_PORT in the install page doesn't change the config of the server - so if you change the port in /install you will have to change it there.

[techknowlogick]

#7286 has been merged. Please re-open this issue if you continue to face this issue after updating to most recent docker image.

[kalsan]

Thanks for the quick reaction! If I understand correctly, this is a problem related to the SSH daemon in the docker container and has nothing to do with Gitea. Of course, /install cannot change the behavior of the contariner's SSH daemon and it also makes sense that by default, Gitea does not provide its own SSH server. All clear then! 👍

[zeripath]

Gitea does provide its own SSH server - and we will be moving the docker to use this by default at some point but at present the docker configuration doesn't use it.

[hollie]

The same issue is still present on the 1.9.3 docker image.

As a workaround, map your own sshd_config file with the correct port to the path /etc/ssh in the docker container.

An example file for port 8022 and user 'git':

Port 8022
Protocol 2

AddressFamily any
ListenAddress 0.0.0.0
ListenAddress ::

LogLevel INFO

HostKey /data/ssh/ssh_host_ed25519_key
HostKey /data/ssh/ssh_host_rsa_key
HostKey /data/ssh/ssh_host_dsa_key
HostKey /data/ssh/ssh_host_ecdsa_key

AuthorizedKeysFile .ssh/authorized_keys

UseDNS no
AllowAgentForwarding no
AllowTcpForwarding no
PrintMotd no

PermitUserEnvironment yes
PermitRootLogin no
ChallengeResponseAuthentication no
PasswordAuthentication no
PermitEmptyPasswords no

AllowUsers git

Banner none
Subsystem sftp /usr/lib/ssh/sftp-server

AcceptEnv GIT_PROTOCOL

[hollie]

In current master branch there are some code changes that should allow to set the SSH ports in the docker image correctly using the option SSH_LISTEN_PORT. See #7829. Those changes are in master and not yet in a stable release.

[hollie]

For later reference in case other people encounter this issue: I've succeeded in updating the OpenSSH server port in the latest docker image by setting an environment variable in the docker-compose.yml file like this:

SSH_PORT=8022

[weshouman]

I believe such edit should go to the docs.
Actually without this tweak the custom SSH port is not possible.

Note: setting either SSH_LISTEN_PORT=8022 or SSH_PORT=8022 would work, with a higher precedence for SSH_LISTEN_PORT
This gist explains more.

[zeripath]

@weshouman it already is in the docs:

https://docs.gitea.io/en-us/install-with-docker/#environments-variables

[weshouman]

I mean it should be explained in the docs that setting that in the app.ini only won't work, and one shall explicitly set that in the environment variable.