When setting up the GCE plugin, I'm unable to get the slave to connect properly. The logs show only an authentication error:
Eventually it throws a "bootstrapresult failed" error:
I can't find any way to begin debugging this issue. The Google Cloud console shows that a new ssh key has been added to the metadata on the freshly provisioned instance, corresponding to the user that Jenkins will use, but I can't get any further logs from the system; logging into the freshly provisioned instance with a different user and examining /var/log/secure doesn't show any ssh login failures.