Maybe start the mount daemon from shell, like this?
/usr/sbin/glusterfs --debug --volfile-server=glnode1 --volfile-id=/testvol 
/mnt/gluster
You could get some useful debug data on your terminal.
However, it's more likely you have a configuration related problem here. 
So the output of the following might also help:
ls -la /var/lib/glusterd/vols/glnode1/
Thanks,
Anirban
From:   Bart?omiej Syryjczyk <bsyryjczyk at kamsoft.pl>
To:     gluster-users at gluster.org
Date:   01/22/2015 09:52 PM
Subject:        [Gluster-users] Mount failed
Sent by:        gluster-users-bounces at gluster.org
I've got problem with mount. Anyone help?
# mount -t glusterfs apache1:/testvol /mnt/gluster
*Mount failed. Please check the log file for more details.*
Log: http://pastebin.com/GzkbEGCw
Oracle Linux Server release 7.0
Kernel 3.8.13-55.1.2.el7uek.x86_64
glusterfs packages from official yum repository
Name        : glusterfs
Arch        : x86_64
Version     : 3.6.1
Release     : 1.el7
-- 
Z powa?aniem,
*Bart?omiej Syryjczyk*
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