The DHT xlator has been fixed in glusterfs-3.6 and several data race issues have been fixed which used to cause data loss during rebalance. With these changes, glusterfs-3.6 and newer clients can correctly co-operate with the rebalance process and not cause any data loss. But clients older than glusterfs-3.6 still have the bugs and could cause data loss when rebalance happens. To prevent the above, rebalance on glusterfs-3.6 and above need to start only if older clients haven't mounted a volume. The gluster cli needs to warn the user of older clients and fail when attempting a rebalance start. Also, the user should be able to bypass the check using 'force' if needed.
REVIEW: http://review.gluster.org/8583 (glusterd: Prevent rebalance starting with old clients) posted (#1) for review on master by Kaushal M (kaushal)
COMMIT: http://review.gluster.org/8583 committed in master by Krishnan Parthasarathi (kparthas) ------ commit 312b339190b7b8f2e38cdd210bf2ee71e53b287e Author: Kaushal M <kaushal> Date: Wed Sep 3 10:50:31 2014 +0530 glusterd: Prevent rebalance starting with old clients Glusterd will prevent rebalance from starting when clients older than glusterfs-v3.6.0 are connected to a volume. This is needed as running rebalance with old clients connected could lead to data loss in some cases. The DHT xlator on newer clients (>= 3.6.0) has been fixed to prevent the data loss issues. Change-Id: If58640236382a2fc13f73f6b43777f01713859f7 BUG: 1136201 Signed-off-by: Kaushal M <kaushal> Reviewed-on: http://review.gluster.org/8583 Tested-by: Gluster Build System <jenkins.com> Reviewed-by: Atin Mukherjee <amukherj> Reviewed-by: Krishnan Parthasarathi <kparthas> Tested-by: Krishnan Parthasarathi <kparthas>
Patch has made into codebase.
This bug is getting closed because a release has been made available that should address the reported issue. In case the problem is still not fixed with glusterfs-3.7.0, please open a new bug report. glusterfs-3.7.0 has been announced on the Gluster mailinglists [1], packages for several distributions should become available in the near future. Keep an eye on the Gluster Users mailinglist [2] and the update infrastructure for your distribution. [1] http://thread.gmane.org/gmane.comp.file-systems.gluster.devel/10939 [2] http://thread.gmane.org/gmane.comp.file-systems.gluster.user