Rollback docker component with AWS Greengrass V2: follow up question

Since Docker -d will exit with a successful code immediately, startup isn't achieving anything in terms of rollback. You'd need the command to exit with a failure in order to rollback.

The better way to do this is use startup without -d which will keep docker in the foreground. Inside your application in the container, use Greengrass IPC to report that your component is healthy by using UpdateState with the RUNNING state: https://docs.aws.amazon.com/greengrass/v2/developerguide/ipc-component-lifecycle.html#ipc-operation-updatestate

If you do not report running within the startup timeout your component will move to ERRORED, then retry 2 more times before becoming BROKEN and triggering the rollback.

Cheers,

Michael

Even when using -d, docker run would exit with 127 status if the command to be execute cannot be found. In your case, the container might find the command to execute but not the some other dependent file. In this case the container starts and docker exits with status 0, but then the container fails because of some other error. Greengrass IPC in your code is the recommended solution in case you are ok in creating a dependency in your container to run in a Greengrass environment. In case you would like to have a container which is agnostic of running in Greengrass or not, you could also add a small watchdog/monitor code that checks if the container is still running after X seconds and exists with non-zero status otherwise.