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Re: [Openldap 2.4.16] Is it possible to force synchronization: files log.xxxx not treated after a crash

On 8/25/09 12:36 PM, Quanah Gibson-Mount wrote:
--On Tuesday, August 25, 2009 12:11 PM -0400 Francis Swasey <Frank.Swasey@uvm.edu> wrote:

On 8/25/09 11:45 AM, Aaron Richton wrote:
On Tue, 25 Aug 2009, Lepoutre Lionel wrote:

My problem is that some data are not synchronised on one of my server
and I
have some "log.xxxx" files in my var/openldap-data/ directory.

When I had an issue with my replicas getting out of sync I developed a
process to slapcat each of the replica's generate what was different from
the master and cause the master to make the changes again (ie, reverse
the master and then revert to what the master knew was correct) which
caused the information to get pushed to the replica's again.  In my case,
the problem turned out to be one of my replica's had too little memory
and was triggering a bug in v2.3 which caused the changes for
delta-syncrepl to not get logged in the accessdb on the provider.

Was this ever fixed in 2.3? Do you have an ITS#? And interesting a replica out of memory would cause the provider not to log data into the accesslog. I'm curious because I'm seeing an issue right now where a ton of deletes are executed, and all the replicas of the master are going into refresh mode on the same entry periodically during the deletes which makes me think that possibly the accesslog is missing writing out some of the changes.

I never filed an ITS for it. I discussed it on this list and you and Howard gave me pointers. I theorize the root cause was the design problem that allowed a consumer to cause the provider to hold a thread on the accesslog (ITS# 5985: replication lockout with syncrepl) and its interaction with the replica that needed more memory caused changes (during high volume change periods) to get backed up so far on the provider that they fell off the end of the queue and were never written to the accesslog.

To find the thread about my issue -- search for the subject "delta-syncrepl missing changes" starting on January 30 and ending around March 20 of this year in the openldap-software list.

Since upgrading the memory on that replica (from 1GB to 5GB), I have not had the problem again.

Frank Swasey                    | http://www.uvm.edu/~fcs
Sr Systems Administrator        | Always remember: You are UNIQUE,
University of Vermont           |    just like everyone else.
  "I am not young enough to know everything." - Oscar Wilde (1854-1900)