replPropertyMetaData sorting

Andrew Bartlett abartlet at samba.org
Fri May 13 11:54:11 UTC 2016


G'Day Metze,

I've been looking, as part of my work at Catalyst, at issues around
corruption of our DB due to replication issues.  Specifically, rename
handling, particularly with subtrees. 

I found and fixed a number of bugs, which you will have seen in the
braches I've proposed.  However, I've been less than satisfied with the
tests for this area, so have been extending them.

I figured you might be very interested in the latest test findings,
regarding replPropertyMetaData.

As far as I can tell, in windows 2012r2, the special sort order for
replPropertyMetaData, that is with the RDN last, simply doesn't exist. 
 Indeed, I wonder if it has always been an artifact of our DRS -> ldb
conversion code in replicated_objects.c

I now have tests that query the server for the replPropertyMetaData and
the DRS equivalent, after each operation, and it shows no such special
sort order.

The only special thing I can find is that the RDN (eg CN) is given a
local invocationID and a local version quite often, while remaining
excluded from replication (name is replicated instead).

See http://git.catalyst.net.nz/gw?p=samba.git;a=shortlog;h=refs/heads/r
epl_move-replPropertyMetaData

Thankfully because this is excluded over DRS, this has not caused
replication corruption.

Finally, I do expect that the patches I have already written will cover
the dbcheck flapping test, which was a genuine DB corruption, due to
mishandling of renamed/deleted objects.

Andrew Bartlett
-- 
Andrew Bartlett                       http://samba.org/~abartlet/
Authentication Developer, Samba Team  http://samba.org
Samba Developer, Catalyst IT          http://catalyst.net.nz/services/samba






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