Try booting with enforcing=0 and if that fixes it, you need to find out what security label is needed for gluster.

Chances are it's easiest to use -o context= mount option on the brick, but if the brick is not exclusive to gluster you'll need chcon -R.

If that's not it, maybe try the gluster client instead of using NFS. See if you get a different result that narrows down what's going on.

My vague recollection is for Samba, without the correct SELinux label, I could neither read nor write.

Chris Murphy