Comment 2 for bug 1834306

Reviewed: https://review.opendev.org/667380
Committed: https://git.openstack.org/cgit/openstack/python-tripleoclient/commit/?id=ee16c094472ee988b85aa81ce8fa9f5da8e61ad9
Submitter: Zuul
Branch: master

commit ee16c094472ee988b85aa81ce8fa9f5da8e61ad9
Author: Harald Jensås <email address hidden>
Date: Tue Jun 25 14:41:02 2019 +0200

    Allow per-subnet DNSNameServers for ctlplane network

    Add a new option ``dns_nameservers`` in the subnet sections
    for the undercloud ctlplane network. By default the option
    is not set, and in that case the ``undercloud_nameservers``
    are used, maintaining the current behaviour.

    This decouples the nameservers used on the undercloud and
    the ones used for the overcloud nodes. In a DCN setting
    different DNS server may be preferred per-site.

    Related-Bug: #1834306
    Change-Id: I0dc03eddf9ea00ff33cd3ae0cdc8f42a4961e89c