RE: OpenLDAP replciation issue with MirrorMode

[Aaron Richton <richton@nbcs.rutgers.edu>]

On Mon, 9 Jan 2012, ZHOU Eric JP wrote:

> This issue only happens when power-off/power cut-off one of the mirror 
> servers, and could be probably prevented by ?sending heart beat? to 
> verify the established connections.

[cutting out openldap-devel; this is usage]

Sure; see the associated ITS and the thread "No replication after power 
failure":

http://www.openldap.org/lists/openldap-bugs/200710/msg00044.html


The only thing I'd note is that "2 hours...is too long" doesn't seem like 
that strong an excuse. It's easily tunable in all modern OS I can think 
of, and in some cases (Linux comes to mind) you can just setsockopt() 
within the application itself so as to not alter the system-wide settings.


Actually, I'm starting to wonder if this should be an option you can pass 
as a syncrepl (really libldap) configuration directive. There's something 
to be said for having aggressive-ish keepalives on server-to-server 
communication (with, hopefully, good bandwidth/latency/communication 
costs/etc.) and keeping your site defaults for "normal" clients. OpenLDAP 
already inched in this direction with the ability to set different 
idletimeout, etc., for the syncrepl client. Is anybody interested in this? 
Maybe I'll do it (or have a student do it) if a few people think it'd 
help...