Enable multipath usage on all OpenStack hosts

[OpenStack Infra]

https://review.openstack.org/257434
Dear bug triager. This bug was created since a commit was marked with DOCIMPACT.
Your project "openstack/openstack-ansible" is set up so that we directly report the documentation bugs against it. If this needs changing, the docimpact-group option needs to be added for the project. You can ask the OpenStack infra team (#openstack-infra on freenode) for help if you need to.

commit e0aa94f6cad4264c9a39ae5ac063c76c4810ce32
Author: Bjoern Teipel <email address hidden>
Date: Mon Dec 14 09:01:06 2015 -0600

    Enable multipath usage on all OpenStack hosts

    This fix adds the multipath-tools package to all nova
    nodes in order to support iscsi-multipath inside nova.
    Additionally when using multipath, the stock AIO limit
    per process (fs.aio-max-nr) is too low and needs to be
    increased to at least 128k.

    In order to enable this feature in nova the following override
    needs to be configured:

    nova_nova_conf_overrides:
      libvirt:
          iscsi_use_multipath: true

    This is a backport combining two patches:
     - https://review.openstack.org/256082
     - https://review.openstack.org/257104

    DocImpact
    Closes-Bug: #1524957
    Change-Id: I36da282043ce864c8a1fb69a1ee02e3a273c14e4

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/277584

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/277584
Committed: https://git.openstack.org/cgit/openstack/openstack-ansible/commit/?id=0acc728faa6ea9b11b95de521fa362efb7e784bf
Submitter: Jenkins
Branch: master

commit 0acc728faa6ea9b11b95de521fa362efb7e784bf
Author: Major Hayden <email address hidden>
Date: Mon Feb 8 15:57:45 2016 -0600

    Docs: Nova iscsi multipath

    Closes-bug: 1533187

    Change-Id: Iaedfc3f122ad6609be3e1003255b3a13055210df

[Davanum Srinivas (DIMS) (dims-v)]

This issue was fixed in the openstack/openstack-ansible 13.0.0 release.