Bitbucket Pipeline build error unexpected system error: step half-completed

Summary

Your Pipelines build fails, and the following error shows on the build page, right next to the build log:

"There was an unexpected system error that may have left your step half-completed. To solve this error, check your step progress and rerun it if you see fit."

Cause

This error is most commonly encountered with builds that utilize self-hosted runners. The error message indicates that the step's container was evicted mid-build. This could happen, among other things, due to:

• power outage

• hardware failure

• network link interruption

• the runner's host machine running out of memory or hard disk space

Solution

Steps are idempotent; this means that Pipelines cannot retry things that were half completed automatically, as it doesn't know where or how it failed, and requires user intervention to determine whether to retry.

• You can monitor memory usage, hard disk space, and the network connectivity on the runner's host machine while your build is running, to determine if this may have caused the error.

• The build log in the repo's Pipelines page or the runner's log may indicate what caused the issue.

The solution depends on the cause. You will first need to address the root cause and then rerun the build and see if it completes this time. If you get repeated failures with this error or you cannot figure out the cause:

• Raise a Support Ticket.

• Share the Pipeline build URL from bitbucket.org.

• Attach any  Pipelines Runner logs to the support ticket.