Debug with SSH
Often the best way to troubleshoot problems is to SSH into a job and inspect log files, running processes, and directory paths. CircleCI gives you the option to access all jobs via SSH. Read our blog post on debugging CI/CD pipelines with SSH.
When you log in with SSH, you are running an interactive login shell. You may be running the command on top of the directory where the command failed the first time, or you may be running the command from the directory one level up from where the command failed (e.g.
~/). Either way, you will not be initiating a clean run. You may wish to execute
ls to ensure that you are in the correct directory.
Please note that a default CircleCI pipeline executes steps in a non-interactive shell. There is a possibility that running steps using an interactive login may succeed, but in non-interactive mode.
Ensure that you have added an SSH key to your GitHub or Bitbucket account.
To start a job with SSH enabled, select the Rerun job with SSH option from the Rerun Workflow dropdown menu.The
Rerun job with SSHfeature is intended for debugging purposes. These jobs will be created inside of the same pipeline as the original job.
To see the connection details, expand the Enable SSH section in the job output where you will see the SSH command needed to connect.
The details are displayed again in the Wait for SSH section at the end of the job.
SSH to the running job (using the same SSH key that you use for GitHub or Bitbucket) to perform whatever troubleshooting you need to.
If you are using the Windows executor you will need to pass in the shell you want to use when using SSH. For example, to run
powershell in your build you would run:
ssh -p <remote_ip> -- powershell.exe. Consider reading the Hello world on Windows page to learn more.
The job virtual machine (VM) will remain available for an SSH connection for 10 minutes after the pipeline finishes running and then automatically shut down (or you can cancel it). After you SSH into the job, the connection will remain open for one hour for customers on the Free plan, or two hours for all other customers.
If your job has parallel steps, CircleCI launches more than one VM to perform them. You will see more than one ‘Enable SSH’ and ‘Wait for SSH’ section in the job output.
Debugging: “permission denied (publickey)”
If you run into permission issues trying to SSH to your job, try the following in the sections below.
Ensure authentication with GitHub/Bitbucket
A single command can be used to test that your keys are set up as expected.
For GitHub, run:
Or, for Bitbucket, run:
ssh -Tv firstname.lastname@example.org
You should see both the following in the output:
$ Hi :username! You've successfully authenticated...
$ logged in as :username.
If you do not see output like above, you can try troubleshooting with the following:
Ensure authenticating as the correct user
The user that triggered the rerun is the user that is required to authenticate. You will need to make sure that your username is in the ‘Enable SSH’ step.
If you have multiple accounts, double-check that you are authenticated as the right one. In order to SSH into a CircleCI build, the username must be one which has access to the project being built.
If you are authenticating as the wrong user, you can try to resolve this by offering a different SSH key with
ssh -i. See the next section for guidance on confirming which key is being offered.
Ensure the correct key is offered to CircleCI
If you have verified that you can authenticate as the correct user, but you are still getting “Permission denied” from CircleCI, you may be offering the wrong credentials to CircleCI.
Check which key is being offered that authenticates you, by running:
$ ssh -v email@example.com
$ ssh -v firstname.lastname@example.org
In the output, look for a sequence like this:
debug1: Offering public key: /Users/me/.ssh/id_ed25519_github <...> debug1: Authentication succeeded (publickey).
This sequence indicates that the key
/Users/me/.ssh/id_ed25519_github is the one which your VCS accepted.
Next, run the SSH command for your CircleCI job, but add the
-v flag. In the output, look for one or more lines like this:
debug1: Offering public key: ...
Make sure that the key which your VCS accepted (in our example,
/Users/me/.ssh/id_ed25519_github) was also offered to CircleCI.
If it was not offered, you can specify it via the
-i command-line argument to SSH. For example:
$ ssh -i /Users/me/.ssh/id_ed25519_github -p 64784 184.108.40.206
When you add the
-v flag, you can also run multiple options in verbose mode to get more details, for example:
$ ssh -vv email@example.com
or the maximum of
$ ssh -vvv firstname.lastname@example.org
Help make this document better
This guide, as well as the rest of our docs, are open source and available on GitHub. We welcome your contributions.
- Suggest an edit to this page (please read the contributing guide first).
- To report a problem in the documentation, or to submit feedback and comments, please open an issue on GitHub.
- CircleCI is always seeking ways to improve your experience with our platform. If you would like to share feedback, please join our research community.
Our support engineers are available to help with service issues, billing, or account related questions, and can help troubleshoot build configurations. Contact our support engineers by opening a ticket.
You can also visit our support site to find support articles, community forums, and training resources.
CircleCI Documentation by CircleCI is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.