Symptoms
Appian engine(s) are unable to start due to a CRASHLOOPBACKOFF state. The following error is printed when trying to start the affected engine:
Starting <engine_name>
<engine_name>: Unable to start engine because it is currently CRASHLOOPBACKOFF. Can only start engines which are DOWN
Manually trying to start the engine also fails with the same error.
Cause
Appian introduced enhancements to automatically recover engines that have gone down. As a part of this improvement, when an engine fails to start back up, it will enter a CRASHLOOPBACKOFF state where the engine will automatically attempt to restart on an increasing interval. In order to manually start the engine once it is in this state, the engine must be fully stopped and started again.
Action
Stop the affected engines and start them again as mentioned in the documentation.
Affected Versions
This article applies to all versions of Appian.
Last Reviewed: November 2019