Bug 1386516

+++ This bug was initially created as a clone of Bug #1386172 +++

Description of problem:
=======================
UUID is showing zeros in the event message for the peer probe operation.

{u'message': {u'host': u'NODE_IP', u'uuid': u'00000000-0000-0000-0000-000000000000'}, u'event': u'PEER_CONNECT', u'ts': 1476787104, u'nodeid': u'50687898-88b3-4157-9f13-1c32266f83be'}

For complete event messages check the next comment 


Version-Release number of selected component (if applicable):
============================================================
glusterfs-3.8.4-2


How reproducible:
=================
Always


Steps to Reproduce:
===================
1. Have gluster events setup with two nodes
2. Do peer probe operation
3. Check the event message generated by the peer probe command

Actual results:
===============
UUID is showing zeros in the event message for the peer probe operation.



Expected results:
=================
It should show correct UUID in the event message.


Additional info:

--- Additional comment from Red Hat Bugzilla Rules Engine on 2016-10-18 06:46:51 EDT ---

This bug is automatically being proposed for the current release of Red Hat Gluster Storage 3 under active development, by setting the release flag 'rhgs‑3.2.0' to '?'. 

If this bug should be proposed for a different release, please manually change the proposed release flag.

--- Additional comment from Byreddy on 2016-10-18 06:53:53 EDT ---

Events messages for peer probe operation:
=========================================

{u'message': {u'host': u'10.70.41.165', u'uuid': u'00000000-0000-0000-0000-000000000000'}, u'event': u'PEER_CONNECT', u'ts': 1476787104, u'nodeid': u'50687898-88b3-4157-9f13-1c32266f83be'}

======================================================================================================================

10.70.43.190 - - [18/Oct/2016 16:03:44] "POST /listen HTTP/1.1" 200 -
{u'message': {u'host': u'dhcp43-190.lab.eng.blr.redhat.com', u'uuid': u'00000000-0000-0000-0000-000000000000'}, u'event': u'PEER_CONNECT', u'ts': 1476787104, u'nodeid': u'96a86504-3612-45db-8ba9-3c458881dcfe'}

======================================================================================================================

10.70.41.165 - - [18/Oct/2016 16:03:45] "POST /listen HTTP/1.1" 200 -
{u'message': {u'host': u'10.70.41.165'}, u'event': u'PEER_ATTACH', u'ts': 1476787105, u'nodeid': u'50687898-88b3-4157-9f13-1c32266f83be'}

======================================================================================================================

10.70.43.190 - - [18/Oct/2016 16:03:45] "POST /listen HTTP/1.1" 200 -

--- Additional comment from Atin Mukherjee on 2016-10-19 03:21:13 EDT ---

RCA:

When a new node is probed, on the first RPC_CLNT_CONNECT peerctx->uuid is set to NULL as the same is yet to be populated. However the subesquent (dis)connect events would be carrying the valid UUIDs.

The way to solve this issue is to conditionally populate UUIDs. If EVENT_PEER_CONNECT has to be generated for the first RPC_CLNT_CONNECT which is because of a peer probe trigger the event would only have hostname whereas for the rest of the other cases the event will populate uuid along with hostname.