I expirience the very same on FreeBSD since quite some versions already - in fact since 2010. I had to develope a workaround which is a monitoring script. It starts the service again everytime it died. The root cause could never be found. Please find the link below for further information:
https://forums.freebsd.org/threads/openldap-slapd-dies-sporadically.47634/
Best regards
Am 28.12.15 um 10:28 schrieb Dieter Klünter:
Am Mon, 28 Dec 2015 10:31:35 +0400 schrieb Jephte Clain jephte.clain@univ-reunion.fr:
hello all,
I upgraded to OpenLDAP 2.4.43 three weeks ago. It runs on debian squeeze 64bits lts it is built from sources with the fix from ITS#8330
Since the upgrade, it keeps crashing regularly (I would say once every 2 to 5 days) However, there isn't anything in the logs: no message, no error, no nothing
slapd no longer runs, I restart it, and it runs ok until the next crash
now I don't know how to debug that. I could downgrade to the previous version (2.4.41) which worked fine, but as our university is closed until 01/11, this is the perfect time to investigate. I still don't know if it's a bug in 2.4.43 or a misconfiguration for which previous versions was forgiving
What are your advice to track down the cause for the crash?
Check whether openldap has been built with --enable-debug=yes. If so set ulimit -c unlimited, which hopefully will create a core dump on a crash.
-Dieter