Description of problem:
Hi,
I am trying to mount a gluster snapshot created but fails.

Version-Release number of selected component (if applicable):
sh-4.2#  gluster --version
glusterfs 3.12.1





How reproducible:

sh-4.2# mount -t glusterfs 192.168.10.100:/snaps/snap1/vol_15553024b879f7f3a158a9168f419e78  /mnt/snaptesting/   
Mount failed. Please check the log file for more details.
sh-4.2# 
sh-4.2# 
sh-4.2# 
sh-4.2# cat /var/log/glusterfs/mnt-snaptesting.log
[2018-02-15 11:13:21.900986] I [MSGID: 100030] [glusterfsd.c:2496:main] 0-/usr/sbin/glusterfs: Started running /usr/sbin/glusterfs version 3.12.1 (args: /usr/sbin/glusterfs --volfile-server=192.168.10.100 --volfile-id=snaps --subdir-mount=/snap1/vol_15553024b879f7f3a158a9168f419e78 /mnt/snaptesting)
[2018-02-15 11:13:21.904583] W [MSGID: 101002] [options.c:995:xl_opt_validate] 0-glusterfs: option 'address-family' is deprecated, preferred is 'transport.address-family', continuing with correction
[2018-02-15 11:13:21.908107] I [MSGID: 101190] [event-epoll.c:613:event_dispatch_epoll_worker] 0-epoll: Started thread with index 1
[2018-02-15 11:13:21.908444] E [glusterfsd-mgmt.c:1796:mgmt_getspec_cbk] 0-glusterfs: failed to get the 'volume file' from server
[2018-02-15 11:13:21.908455] E [glusterfsd-mgmt.c:1932:mgmt_getspec_cbk] 0-mgmt: failed to fetch volume file (key:snaps)
[2018-02-15 11:13:21.908604] W [glusterfsd.c:1347:cleanup_and_exit] (-->/lib64/libgfrpc.so.0(rpc_clnt_handle_reply+0x90) [0x7f577e412e60] -->/usr/sbin/glusterfs(mgmt_getspec_cbk+0x680) [0x55a57f9c0ef0] -->/usr/sbin/glusterfs(cleanup_and_exit+0x6b) [0x55a57f9ba18b] ) 0-: received signum (0), shutting down
[2018-02-15 11:13:21.908627] I [fuse-bridge.c:5833:fini] 0-fuse: Unmounting '/mnt/snaptesting'.
[2018-02-15 11:13:21.912862] I [fuse-bridge.c:5838:fini] 0-fuse: Closing fuse connection to '/mnt/snaptesting'.
[2018-02-15 11:13:21.913420] W [glusterfsd.c:1347:cleanup_and_exit] (-->/lib64/libpthread.so.0(+0x7e25) [0x7f577d4a9e25] -->/usr/sbin/glusterfs(glusterfs_sigwaiter+0xe5) [0x55a57f9ba365] -->/usr/sbin/glusterfs(cleanup_and_exit+0x6b) [0x55a57f9ba18b] ) 0-: received signum (15), shutting down
sh-4.2# 
sh-4.2# 
sh-4.2# ls /var/lib/glusterd/vols/
heketidbstorage/                      vol_15553024b879f7f3a158a9168f419e78/ 
sh-4.2# ls /var/lib/glusterd/vols/vol_15553024b879f7f3a158a9168f419e78/
bricks
cksum
info
node_state.info
snapd.info
trusted-vol_15553024b879f7f3a158a9168f419e78.tcp-fuse.vol
vol_15553024b879f7f3a158a9168f419e78.192.168.10.100.var-lib-heketi-mounts-vg_2d062529eb274d546fb6e515d48a92fe-brick_cc3debb47e957834ac81b3d4f5048674-brick.vol
vol_15553024b879f7f3a158a9168f419e78.192.168.10.101.var-lib-heketi-mounts-vg_e7389b53a8e47359341d7576d1f3b2a2-brick_a7b9f5b4ec100710c23eeeeafdc856c3-brick.vol
vol_15553024b879f7f3a158a9168f419e78.192.168.10.102.var-lib-heketi-mounts-vg_1595ffb6e754f83ceebeae2e19d77db8-brick_9495ae770aeb6be5f6fc0a93b39d192e-brick.vol
vol_15553024b879f7f3a158a9168f419e78.tcp-fuse.vol
sh-4.2# ls /var/lib/glusterd/vols/vol_15553024b879f7f3a158a9168f419e78/ -l
total 56
drwxr-xr-x. 2 root root 4096 Feb 15 10:55 bricks
-rw-------. 1 root root   16 Feb 15 10:55 cksum
-rw-------. 1 root root  887 Feb 15 10:55 info
-rw-------. 1 root root  168 Feb 15 10:55 node_state.info
-rw-------. 1 root root   13 Feb 15 10:55 snapd.info
-rw-------. 1 root root 4132 Feb 15 10:55 trusted-vol_15553024b879f7f3a158a9168f419e78.tcp-fuse.vol
-rw-------. 1 root root 6527 Feb 15 10:55 vol_15553024b879f7f3a158a9168f419e78.192.168.10.100.var-lib-heketi-mounts-vg_2d062529eb274d546fb6e515d48a92fe-brick_cc3debb47e957834ac81b3d4f5048674-brick.vol
-rw-------. 1 root root 6527 Feb 15 10:55 vol_15553024b879f7f3a158a9168f419e78.192.168.10.101.var-lib-heketi-mounts-vg_e7389b53a8e47359341d7576d1f3b2a2-brick_a7b9f5b4ec100710c23eeeeafdc856c3-brick.vol
-rw-------. 1 root root 6527 Feb 15 10:55 vol_15553024b879f7f3a158a9168f419e78.192.168.10.102.var-lib-heketi-mounts-vg_1595ffb6e754f83ceebeae2e19d77db8-brick_9495ae770aeb6be5f6fc0a93b39d192e-brick.vol
-rw-------. 1 root root 3790 Feb 15 10:55 vol_15553024b879f7f3a158a9168f419e78.tcp-fuse.vol
sh-4.2# 
sh-4.2# 
sh-4.2# ls /var/lib/glusterd/vols/vol_15553024b879f7f3a158a9168f419e78/bricks/
192.168.10.100:-var-lib-heketi-mounts-vg_2d062529eb274d546fb6e515d48a92fe-brick_cc3debb47e957834ac81b3d4f5048674-brick
192.168.10.101:-var-lib-heketi-mounts-vg_e7389b53a8e47359341d7576d1f3b2a2-brick_a7b9f5b4ec100710c23eeeeafdc856c3-brick
192.168.10.102:-var-lib-heketi-mounts-vg_1595ffb6e754f83ceebeae2e19d77db8-brick_9495ae770aeb6be5f6fc0a93b39d192e-brick
sh-4.2# 
sh-4.2# 
sh-4.2# ip addr show eth1 
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 52:54:00:e7:54:32 brd ff:ff:ff:ff:ff:ff
    inet 192.168.10.100/24 brd 192.168.10.255 scope global eth1
       valid_lft forever preferred_lft forever
    inet6 fe80::5054:ff:fee7:5432/64 scope link 
       valid_lft forever preferred_lft forever
sh-4.2# 
sh-4.2# gluster snapshot status 

Snap Name : snap1
Snap UUID : 0523abd9-9d6d-48ee-b8b3-4f5dde90d82a

	Brick Path        :   192.168.10.101:/run/gluster/snaps/9e99eb26fa8c4d2480bd4f3d9ffdd17c/brick1/brick
	Volume Group      :   vg_e7389b53a8e47359341d7576d1f3b2a2
	Brick Running     :   Yes
	Brick PID         :   12447
	Data Percentage   :   1.34
	LV Size           :   100.00g


	Brick Path        :   192.168.10.100:/run/gluster/snaps/9e99eb26fa8c4d2480bd4f3d9ffdd17c/brick2/brick
	Volume Group      :   vg_2d062529eb274d546fb6e515d48a92fe
	Brick Running     :   Yes
	Brick PID         :   14418
	Data Percentage   :   1.34
	LV Size           :   100.00g


	Brick Path        :   192.168.10.102:/run/gluster/snaps/9e99eb26fa8c4d2480bd4f3d9ffdd17c/brick3/brick
	Volume Group      :   vg_1595ffb6e754f83ceebeae2e19d77db8
	Brick Running     :   Yes
	Brick PID         :   12424
	Data Percentage   :   1.34
	LV Size           :   100.00g

sh-4.2# gluster snapshot list 
snap1
sh-4.2# 
sh-4.2#