Exit Code 255 in CI: What It Means and How to Fix It
Exit code 255 usually means "exit status out of range" or a fatal error from tools like SSH and Terraform.
Code 255 is what you get from exit -1 (wraps to 255) and from several tools’ fatal failures.
What it means
A generic fatal error; SSH returns 255 on connection failure, and exit -1 becomes 255.
Common causes
- SSH could not connect (255).
- A script ran
exit -1. - A tool signalled a fatal, unspecified error.
How to fix it
For SSH, debug the connection (host key, auth, network). Otherwise read the tool’s fatal output.
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