Hello,
Over night I have added a new Jenkins instance to the stack but unfortunately it came with a broken Docker daemon. Thus any CI job running on that instance would fail to download any image.
The symptom looked like:
Unable to find image 'docker-registry.wikimedia.org/releng/castor:0.2.0' locally 0.2.0: Pulling from releng/castor docker: open /var/lib/docker/tmp/GetImageBlob682696395: no such file or directory. Build step 'Execute shell' marked build as failure
The root cause is that I have pointed Docker to a new disk partition but forgot to restart the Docker daemon :-\
https://phabricator.wikimedia.org/T222131
If one one of your change got affected, simply commenting 'recheck' should get the job running again as usual.