Bug 1422499

Description of problem:

Version on 4 of the oVirt engine will support two versions of the API:
version 3, which will be backwards compatible with older versions of the
engine, and version 4, which won't be compatible. The default used by the
server will be version 4, but clients can explicitly request a version
of the API using the "Version" header or the "/v3" URL prefix. The
header is the preferred mechanism because it is just ignored by older
versions of the server. This patch modifies the oVirt fence agent so
that the path and version of the API are configuratble, and so that
their default values work correctly with version 3 compatibility mode of
the API.

From upstream patch:
https://github.com/ClusterLabs/fence-agents/pull/71


Version-Release number of selected component (if applicable):

In one particular case fencing doesn't work with 4.0.11-47.el7_3.2 in RHEV 3.6:

Upgrading the fence-agents to 4.0.11-47.el7_3.2 breaks fencing, and downgrading it back to 4.0.11-27.el7_2.7 fixes it.
~~~
fence-agents-rhevm-4.0.11-27.el7_2.7 -- working
fence-agents-rhevm-4.0.11-47.el7_3.2 -- not working
~~~


Additional info:

We did a diff of the two versions [1] and we found out that in the new version we have a hard-coded api path (i.e. /api/) which is not backwards-compatible with RHEV 3.x:
~~~
84,87d82
<   if opt.has_key("--api-path"):
<       api_path = opt["--api-path"]
<   else:
<       api_path = "/ovirt-engine/api"
89c84
<   url += "//" + opt["--ip"] + ":" + str(opt["--ipport"]) + api_path + "/" + command
---
>   url += "//" + opt["--ip"] + ":" + str(opt["--ipport"]) + "/api/" + command
~~~

The problem seems to be resolved upstream already:
https://github.com/ClusterLabs/fence-agents/pull/71/files

Can we get (rebase/cherry pick) the patch to the RH fence driver as well?


[1] http://pastebin.com/cSnMsryp