tripleo job are overwriting nameserver with 8.8.8.8

[Paul Belanger]

tripleo jobs should not be using google DNS servers directly, this results in rate limiting by google.com and eventually results in:

       http://mirror.ca-ymq-1.vexxhost.openstack.org:8080/buildlogs.centos/centos/7/cloud/x86_64/openstack-pike/common/python2-fasteners-0.14.1-6.el7.noarch.rpm: [Errno 14] curl#6 - "Could not resolve host: mirror.ca-ymq-1.vexxhost.openstack.org; Unknown error"

http://logs.openstack.org/83/493383/2/gate/gate-tripleo-ci-centos-7-scenario002-multinode-oooq-puppet/2777163/logs/undercloud/home/jenkins/failed_deployment_list.log.txt.gz

You can see jobs have been setup and forced to use 8.8.8.8:
  http://logs.openstack.org/37/493937/3/gate/gate-tripleo-ci-centos-7-scenario002-multinode-oooq/4e30192/logs/undercloud/etc/resolv.conf.txt.gz

overwriting the original:
  http://logs.openstack.org/37/493937/3/gate/gate-tripleo-ci-centos-7-scenario002-multinode-oooq/4e30192/logs/undercloud/etc/resolv.conf.save.gz

I believe this is because undercloud_nameservers = 8.8.8.8 in:

  http://logs.openstack.org/37/493937/3/gate/gate-tripleo-ci-centos-7-scenario002-multinode-oooq/4e30192/logs/undercloud/home/jenkins/undercloud.conf.txt.gz

[Sagi (Sergey) Shnaidman (sshnaidm)]

@Paul, yes, it always was the case - to use 8.8.8.8 as DNS. So what do you suggest to use instead of it?

[wes hayutin (weshayutin)]

<pabelanger> undercloud_nameservers = 8.8.8.8
<pabelanger> that is wrong
<pabelanger> we need to stop defaulting to google DNS
* itlinux (~textual@2602:30a:c0aa:3fb0:99d6:ce31:d40a:e76d) has joined
<pabelanger> and use unbound service with is 127.0.0.1

[Paul Belanger (pabelanger)]

This hasn't always been this, for some reason it keeps getting changed back to google DNS which results in rate limiting and DNS failures.

For now, you shouldn't need to manage DNS on nodes from nodepool, we spend a lot of effort making sure they are using our local unbound service which is configured as forward zones.

I would suggest either removing your logic to stop managing DNS or also set it to 127.0.0.1.

This also applies to any nodes you are launching in the overcloud, all DNS requests should be hitting unbound first, not google.

Happy to talk more about this in IRC.

[Sagi (Sergey) Shnaidman (sshnaidm)]

https://review.openstack.org/#/c/494545/