Gitlab Runner errors and solutions

Error 1) open /root/.ssh/known_hosts: no such file or directory

Using SSH executor...

ERROR: Preparation failed: ssh command Connect() error:
getting host key callback: open /root/.ssh/known_hosts: 
no such file or directory

Will be retried in 3s ...

Solution:

Follow the steps to resolve:

1) Login to gitlab instance via SSH
2) Become sudo via:

sudo su

3) Now, you need to connect gitlab instance to the host where runner is try to connect

ssh <host-username>@<host-ip>

<host-username> and <host-ip> should match with the gitlab runner, it will ask for password then it will ask to accept key fingerprint.

Now, try to run the job with the runner. It should be working

Error 2) Job failed: prepare environment: Process exited with status 1.

If you are getting following error in your when running gitlab ci/cd job via gitlab-runner:

ERROR: Job failed: prepare environment: Process exited with status 1. 
Check https://docs.gitlab.com/runner/shells/index.html#shell-profile-loading 
for more information

Solution:

Run following commands on the server where gitlab runner trying to login:

find / -name .bash_logout

and delete following files if exist

sudo rm -r /home/gitlab-runner/.bash_logout
sudo rm -r /home/<username>/.bash_logout

Try to re-run the jobs it should be working.

Error 3) handshake failed: knownhosts: key is unknown

ERROR: Preparation failed: ssh command Connect() error: ssh Dial() error: ssh: handshake failed: knownhosts: key is unknown

Solution:

Solution A

Verify your login credentials

Solution B

Verify that SSH port is open

Solution C

Edit your runner and add disable_strict_host_key_checking = true

sudo nano /etc/gitlab-runner/config.toml

[[runners]]
  name = "..."
  url = "..."
  token = "..."
  executor = "ssh"
  [runners.custom_build_dir]
  [runners.cache]
    [runners.cache.s3]
    [runners.cache.gcs]
    [runners.cache.azure]
  [runners.ssh]
    user = "..."
    password = "..."
    host = "..."
    port = "..."
    disable_strict_host_key_checking = true

Then restart the gitlab-runner

sudo gitlab-runner restart

Solution D

If you're using WHM as your hosting control panel, enable following settings:

SSH Password Authorization Tweak