Gluster - NFS-Ganesha won't start after initial setup

Issue

• After following the steps in The RHGS Installation Guide to configure NFS-Ganesha, I'm encountering the following errors in /var/log/ganesha.log:

08/12/2017 21:35:23 : epoch 9a730000 : ganesha-test : ganesha.nfsd-9556[main] Allocate_sockets :DISP :WARN :System may not have V6 intfs configured error 97(Address family not supported by protocol)
08/12/2017 21:35:23 : epoch 9a730000 : ganesha-test : ganesha.nfsd-9556[main] nfs_Init_svc :DISP :CRIT :Cannot acquire credentials for principal nfs
08/12/2017 21:35:23 : epoch 9a730000 : ganesha-test : ganesha.nfsd-9556[main] Register_program :DISP :FATAL :Cannot register NFS V3 on UDPv6
08/12/2017 21:35:23 : epoch 9a730000 : ganesha-test : ganesha.nfsd-9556[main] unregister_fsal :FSAL :CRIT :Unregister FSAL GLUSTER with non-zero refcount=2
08/12/2017 21:35:23 : epoch 9a730000 : ganesha-test : ganesha.nfsd-9556[main] glusterfs_unload :FSAL :CRIT :FSAL Gluster unable to unload.  Dying ...