GitHub Actions "Runner listener exited with error code null"

The runner listener process exited without a clean code (null), meaning it crashed or was killed rather than shutting down gracefully, taking the runner offline.

What this error means

The runner service log shows "Runner listener exited with error code null" and the runner goes Offline. With auto-restart it may flap between Online and Offline.

github-actions

Runner listener exited with error code null
Runner listener exit with terminated error, stop the service, no retry needed.

Common causes

Host resource exhaustion killed the process

An OOM kill or disk-full condition terminated the listener with no exit code.

Corrupted runner install or bad config

A partial upgrade, corrupted .runner/.credentials files, or incompatible binary makes the listener crash on start.

How to fix it

Recover the runner

Check host logs for an OOM kill or disk-full event at the crash time.
Inspect the runner _diag logs for the underlying exception.
Reconfigure with a clean ./config.sh if the install looks corrupted.
Restart the service and confirm it stays Idle.

Use managed runners

Managed runners remove the listener-maintenance burden; capacity is monitored and replaced automatically rather than flapping offline on a crash.

How to prevent it

Keep hosts off memory and disk limits.
Apply runner upgrades cleanly and atomically.
Alert when a runner flaps offline repeatedly.