Re: How to detect a corrupt database?

[Jordi Espasa Clofent <jespasac@minibofh.org>]

> If your disks are working and haven't run out of space, database 
> corruption pretty much never happens. You probably should describe the 
> situation that leads you to believe there was a corruption. You should 
> also list the versions of software in use.

I've three OpenLDAP (one provider, two consumers) as central account 
server (implementing also sudo overlay).

xen-ldap01:/# dpkg -l | grep slapd && uname -a && cat /etc/debian_version
ii  slapd                            2.4.11-1                OpenLDAP 
server (slapd)
Linux xen-ldap01 2.6.18-6-xen-amd64 #1 SMP Wed Oct 15 11:49:51 UTC 2008 
x86_64 GNU/Linux
5.0

Some concrete users (3 of 35) get errors when they try to login; only 
them, the others alwasy can login without problem.
The 3 OpenLDAP server are balanced, so I can reduce the problem. After 
some test, it was clear that the "problem" remains in xen-ldap03 (one of 
the two consumers).

Really I don't know if the ddbb was corrupted or not, but when I did:

$ /etc/init.d/slapd stop
$ cd /var/lib/openldap/ && rm *
$ /etc/init.d/slapd start

the problem disappears. So, I tend to think the problem was some record 
in ddbdd.
Maybe I'm wrong.

> > * ¿How I can detect a corrupt database?
>
> slapd will detect unclean shutdowns automatically, and automatically 
> recover from them.

Great. ¿It is showed with normal debug level (256)?

> > * ¿Is there any tool/command to check the ddbb health (DBD4)?
>
> slaptest will tell you if there was an unclean shutdown.

;)

> > * ¿What can I do if the corrupted database is the provider database?
>
> Restore from a backup.

Yep. I've done a simple cronjob based on slapcat tool.

--
Thanks,
Jordi Espasa Clofent