FC5 system hanging, is cyrus the culprit?

[Mike]

Morning,

I have an up to date FC5 box that runs openldap, samba, cyrus,
mysql, and bacula. This box recently started hanging in general,
not responding to ssh nor telnet logins, any active session when
the hanging started would also hang if I issued any command that
talked to the filesystem. I could do tails on files (/var/log/messages)
that I knew exist, and I could do a 'df -k', but the session would
hang if I did a 'ls -ltr' (to see the most recently changed file).

I thought I had a filling file system. I use and monitor syslog
quite heavily and thought /var was filling and causing problems
with ldap (/var/lib/ldap) or named (/var/lib/named). I moved these
files to their own file systems and mount points to prevent problems.

The last time the box froze (last night) I could see that none of
the file systems were full. Last night I stopped bacula, saslauthd,
and cyrus-imapd. The box stayed up last night.

Could cyrus be a problem. I have nothing in any logs when the
system hangs. What can I look for?

Mike

[mikee at host ~]$ rpm -qa | grep cyrus
cyrus-imapd-2.3.1-2.7.fc5
cyrus-sasl-lib-2.1.21-10
cyrus-sasl-2.1.21-10
cyrus-sasl-ldap-2.1.21-10
cyrus-sasl-devel-2.1.21-10
cyrus-imapd-devel-2.3.1-2.7.fc5
cyrus-imapd-utils-2.3.1-2.7.fc5