I have a 5 node Openshift cluster split across 2 AZs; our colocation center and AWS, with a master in each AZ and the rest being nodes.
We setup our cluster with the Ansible script, and somewhere during the setup, the EC2 instance's private hostname were picked up and registered as node names of the nodes in AWS, which is a bit annoying as that deviates from our hostname conventions and is rather difficult to read, and it's not something that can be changed post setup.
It didn't help that parts of the admin operations seem to be using the EC2 instance's private hostname, so I get errors like this:
# oc logs logging-fluentd-shfnu
Scheduling system related pods on the AWS instances works (router, fluentd), though any build pods that lands up on EC2s never gets built, and just eventually times out; my suspicion is that the build process monitors depends on the hostname which can't be reached from our colocation center master (which we use as a primary), and hence breaks.
I'm unable to find much detail on this behaviour.
1. Can we manually change the hostname of certain nodes?
2. How do we avoid registering EC2 nodes with their private hostnames?