Comment 2 for bug 1763776

Reviewed: https://review.openstack.org/561273
Committed: https://git.openstack.org/cgit/openstack/puppet-tripleo/commit/?id=6d510547965350338d0d11c4114f67bc6c3d9702
Submitter: Zuul
Branch: master

commit 6d510547965350338d0d11c4114f67bc6c3d9702
Author: Michele Baldessari <email address hidden>
Date: Sun Apr 15 19:49:49 2018 +0200

    Partially revert "Fail more gracefully when passed an empty ip"

    This reverts the manifests/haproxy.pp parts of
    commit 4c7ca4cbc385fa70438015ebc91b8692c00d46e7.

    The reverted commit made it such that you can not set a
    hostname as undercloud_public_host in undercloud.conf. This
    is required so that the UI can be accessed by hostname
    externally as well as to make the Undercloud API accessible
    externally. We keep the parts of that change that verify if
    the haproxy VIP for pacemaker is a proper IP as it can
    happen that a misconfigured network template causes empty
    strings and the deploy will fail in a very odd way.

    Change-Id: I57eeb2dd26336465627593d633c63b92da42e71d
    Closes-Bug: #1763776