We are experiencing an issue whereby the LDAP server seems to crash
and cannot be contacted about once a week. OX services have to be
restarted in order to resume normal service. Users report that they cannot
log into their mail either via an IMAP client or the webmail interface.

The server is not particularly busy at the time of the crashes.

Here is the relevant section of the logs:

Aug 13 09:39:00 mail saslauthd[5082]: pam_ldap: ldap_starttls_s: Can't 
contact LDAP server
Aug 13 09:39:00 mail saslauthd[5082]: DEBUG: auth_pam: pam_authenticate 
failed: Authentication failure
Aug 13 09:39:00 mail saslauthd[5082]: do_auth         : auth failure: 
[user=db139a] [service=imap] [realm=] [mech=pam] [reason=PAM auth error]
Aug 13 09:39:00 mail imap[11899]: badlogin: localhost [127.0.0.1] 
plaintext db139a SASL(-13): authentication failure: checkpass failed
Aug 13 09:39:00 mail PAM-warn[5066]: function=[pam_sm_acct_mgmt] 
service=[imap] terminal=[<unknown>] user=[db139a] ruser=[<unknown>] 
rhost=[<unknown>]
 
We are using OX5 build 5637 (hymalia) on a SLES9 box.

Has anyone seen this behaviour before?

Mark