Description of problem:
We recently debugged a bug that was the result of non-working DNS resolution and made RabbitMQ fail during deployment without helpful errors, as the socket bindings got really slow without working DNS.
This highlighted the need for a DNS check during the network validation, maybe with a configurable host to resolve that will work even in environments where the resolution is limited to local names.
This idea came out of bug #1304423
Verified in: openstack-tripleo-validations-8.4.0-1.el7ost.noarch
This was implemented as a pre-deployment validation only, and will run on the undercloud. The user cannot run this on the overcloud during the deployment, before the services are configured, so deployments may still fail if DNS is misconfigured on the overcloud.
Atilla - consider opening a new bug to do a similar test during the deployment, and stop the deployment with a clear error message if DNS is not working. Or re-open this bug if you feel it's not properly completed.
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.
https://access.redhat.com/errata/RHEA-2018:2086