Description of problem:
-----------------------

I can set the value of cluster.brick-multiplex to literally anything.

ONLY boolean values should be set for the tunable.


* set to a random string of chars* :

[root@gqas009 ~]# 
[root@gqas009 ~]# gluster v set all cluster.brick-multiplex  fe
volume set: success
[root@gqas009 ~]# 
[root@gqas009 ~]# gluster v info
 
Volume Name: testvol
Type: Distribute
Volume ID: 383b2632-efdc-4259-bedb-79b5ad3ecdfc
Status: Started
Snapshot Count: 0
Number of Bricks: 1
Transport-type: tcp
Bricks:
Brick1: gqas009.sbu.lab.eng.bos.redhat.com:/bricks/A
Options Reconfigured:
transport.address-family: inet
nfs.disable: on
cluster.brick-multiplex: fe
 
Volume Name: testvol2
Type: Distribute
Volume ID: dc2c6537-a13a-4b68-a744-2380ae13af61
Status: Started
Snapshot Count: 0
Number of Bricks: 1
Transport-type: tcp
Bricks:
Brick1: gqas009.sbu.lab.eng.bos.redhat.com:/bricks/A2
Options Reconfigured:
transport.address-family: inet
nfs.disable: on
cluster.brick-multiplex: fe
[root@gqas009 ~]# 

*set to -1* :

[root@gqas009 ~]# gluster v set all cluster.brick-multiplex  -1
volume set: success
[root@gqas009 ~]# 
[root@gqas009 ~]# 
[root@gqas009 ~]# gluster v info
 
Volume Name: testvol
Type: Distribute
Volume ID: 383b2632-efdc-4259-bedb-79b5ad3ecdfc
Status: Started
Snapshot Count: 0
Number of Bricks: 1
Transport-type: tcp
Bricks:
Brick1: gqas009.sbu.lab.eng.bos.redhat.com:/bricks/A
Options Reconfigured:
transport.address-family: inet
nfs.disable: on
cluster.brick-multiplex: -1
 
Volume Name: testvol2
Type: Distribute
Volume ID: dc2c6537-a13a-4b68-a744-2380ae13af61
Status: Started
Snapshot Count: 0
Number of Bricks: 1
Transport-type: tcp
Bricks:
Brick1: gqas009.sbu.lab.eng.bos.redhat.com:/bricks/A2
Options Reconfigured:
transport.address-family: inet
nfs.disable: on
cluster.brick-multiplex: -1
[root@gqas009 ~]# 




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

glusterfs-server-3.8.4-23.el7rhgs.x86_64

How reproducible:
----------------

Always.