As noted in the redhat bug, it's necessary to run glusterd --xlator-option *.upgrade=on -N once, with regular glusterd stopped, on server machines to generate properly-named volume files. Otherwise mounting by any clients will fail because glusterd cannot locate the volume file for a given key. The change happened in 3.6.2, so any installation prior to that which is upgraded is affected. I'm not sure that this can be done automatically by the ebuild - at least the postinst elog should note it (and point to http://www.gluster.org/community/documentation/index.php/Upgrade_to_3.6 instead of Upgrade_to_3.5, but the issue is not yet noted there either). Best regards, Bernd Reproducible: Always
Thanks for pointing this out Bernd, I've updated the elog with the correct 3.6 upgrade link !