Description of problem:
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currently we only support volumes of replica count 3
Any volume with replica count 2 throws a warning

however glusterfs still create a volume of replica count >3 as below example, without any caution/warning.

[root@dhcp35-190 ~]# gluster v create rep rep 4 server:/gluster/brick1/rep2 $HOSTNAME:/gluster/brick1/rep2 server2:/gluster/brick1/rep2 server3:/gluster/brick1/rep2 
volume create: rep: success: please start the volume to access data



We must throw a warning saying that " replica count other than or greater than  3 is not supported,"


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