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Re: null_callbacks after initial sync


My hunch was since you are in N-Way MultiMaster mode, it should work both ways, and I think that nailed where the problem is

You need two sections with syncrepl.  One for the replication from A to B, and one for the replication from B to A.  Both servers should have both RIDs

See the MirrorMode and N-Way documentation on the Admin24 documentation.  You will see you need both servers to have both RID lines, just be sure the serverID is unique.

http://www.openldap.org/doc/admin24/replication.html#N-Way%20Multi-Master is a good reference.


(p.s.  I'm not sure why the first change replicated though - if I understand correctly, it would have all failed in the one direction)

On Mar 5, 2008, at 11:34 AM, Nick Geron wrote:
Thanks for the reply, Chris.  That hadn't occurred to me.  It seems that
yes, when starting server 2 first and writing to it, replication appears
to work fine.  That got me thinking perhaps there was an issue with the
build or environment issue on the first server, but I can't find any
meaningful discrepancy between the systems.

Something I'm curious about though, is the behavior when the serverID is
set incorrectly.  It's my understanding that in mirror mode, the pair
are configured to use the same RID with different SIDs.  I have been
working with RID 1 and SIDs 1 and 2 for server 1 and 2 respectively.  An
earlier test where I had neglected to change the SID, (rid 1 with two
sid 1) deluged my logs with what looked to be a loop; Gigs of
do_syncrep2 Content Sync Refresh Required and subsequent attempts to sync.

I understand that the config is the source of the problem there.
However, thinking that the success of this morning's test with server 2
as the 'primary,' I wondered if there was some confusion when using rid
1 and sid 1, so I changed server 1 to sid 3.  What I don't understand is
that I see the same log entries/behavior with rid 1, sid 3 and sid 2 as
I did if both systems were set with sid 1.  Can anyone explain that
behavior?  And of course, Chris, what's your hunch with suspecting that
things might work from the second server?

Any input is very much appreciated as my project cannot continue without
a functional mirror.  Thanks!


Chris G. Sellers wrote:
Do you have different behavior if you make the update to ldap server 2
and it tries to replicate to ldap server 1?

On Mar 4, 2008, at 12:20 PM, Nick Geron wrote:
I'm working with a test mirror mode setup on 2.4.7 with db 4.5.20 and
seeing issues with SyncRepl.  Specifically, do_syncrepl fails with an
initial error 0x10 and subsequent 0x14, though at least one modification
is propagated.  To put another way:

*Systems using same ldif to populate and running nearly identical
slapd.conf files (serverID is the only variance).

1) start server 1
2) start server 2
3) add host attribute to posixAccount entry on s-1
4) attribute seen on s-2 but results in the following log
5) no other updates successful until server process restarted.

Mar  4 10:46:14 slapd[22999]: do_syncrep2: rid=001 LDAP_RES_INTERMEDIATE

Chris G. Sellers | NITLE  - Technology Team
734.661.2318 | chris.sellers@nitle.org <mailto:chris.sellers@nitle.org>
AIM: imthewherd | GoogleTalk: cgseller@gmail.com

Chris G. Sellers | NITLE  - Technology Team
AIM: imthewherd | GoogleTalk: cgseller@gmail.com