Description of problem:
=======================

If the slave volume is part of any geo-rep session, then another attempt to use the same slave volume should be restricted. This is currently allowed if the session is already established as root and another attempt is made using user. 

In this case master volume info file is appended with both the slave entries one with slavehostname and another with <user>@slavehostname.

Now, if any one of the geo-rep session is deleted for example root session. All the session gets deleted.

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

glusterfs-3.7.1-14.el7rhgs.x86_64


How reproducible:
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Always

Steps to Reproduce:
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1. Create and start geo-rep session between master and slave {root}
2. Create another geo-rep session between same master ans slave using same slave host but with user account {non-root}

Actual results:
===============

Able to create the session


Expected results:
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If slave is part of any geo-rep session the subsequent attempt to create different geo-rep session should fail