Aaron Richton wrote:
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...
Already done, see the keepalive= keyword in syncrepl config.