[Bugs] [Bug 1597123] Changes to self-heal logic w.r.t. detecting of split-brains

[bugzilla at redhat.com]

https://bugzilla.redhat.com/show_bug.cgi?id=1597123

Worker Ant <bugzilla-bot at gluster.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|POST                        |MODIFIED



--- Comment #2 from Worker Ant <bugzilla-bot at gluster.org> ---
COMMIT: https://review.gluster.org/20433 committed in release-3.12 by "jiffin
tony Thottan" <jthottan at redhat.com> with a commit message- afr: don't treat all
cases all bricks being blamed as split-brain

Problem:
We currently don't have a roll-back/undoing of post-ops if quorum is not
met. Though the FOP is still unwound with failure, the xattrs remain on
the disk.  Due to these partial post-ops and partial heals (healing only when
2 bricks are up), we can end up in split-brain purely from the afr
xattrs point of view i.e each brick is blamed by atleast one of the
others. These scenarios are hit when there is frequent
connect/disconnect of the client/shd to the bricks while I/O or heal
are in progress.

Fix:
Instead of undoing the post-op, pick a source based on the xattr values.
If 2 bricks blame one, the blamed one must be treated as sink.
If there is no majority, all are sources. Once we pick a source,
self-heal will then do the heal instead of erroring out due to
split-brain.

Change-Id: I3d0224b883eb0945785ade0e9697a1c828aec0ae
BUG: 1597123
Signed-off-by: Ravishankar N <ravishankar at redhat.com>
(cherry picked from commit 0e6e8216823c2d9dafb81aae0f6ee3497c23d140)

-- 
You are receiving this mail because:
You are on the CC list for the bug.
Unsubscribe from this bug https://bugzilla.redhat.com/token.cgi?t=F44D2XBaUu&a=cc_unsubscribe