Citadel is crashing my server

citserv is using 102% of CPU

[gcan]

Today I didn't get email from my Debian server with cronjob results.

mail.err file showed the following:

Jul 12 00:23:16 server citadel: BDB: unable to allocate space from the buffer cache
Jul 12 00:23:16 server citadel: cdb_fetch(2): Cannot allocate memory

Top showed that load is about 2 and citserv is using 102% of CPU, and a lot of processes - crontab+sendmail, crontab+sendmail... And the number of crontab and sendmail processes was groving. I tried to restart or stop sendmail. It didn't work - it was just like freezed. I tried to restart Apache. It took some 5 minutes.

I had to kill manually all sendmail and crontab processes. After that server load dropped to 0 and sendmail started to work.

Any ideas what's going on?

Thanks.

[lammert]

The BDB error indicates an error in the Berkeley database subsystem which is used by Citadel for its storage. One option could be that you are running out of RAM, but it is also possible that the database structure itself corrupted.

One reported problem with Citadel is that the database system can get corrupted with an upgrade of the Citadel version without upgrading the database structure. Was there any recent update of Citadel installed on your server that you are aware of?

[gcan]

Lammert, thank you for your reply.

No, there were no upgrades on my server at this time. Some 1 month there were no changes, new installations, upgrades. Everything was working fine till yesterday.

I am ot running out of RAM and the problem appeared at night when there is almost no activity on the server.

Do I need citadel server at all?

Thanks.

[gcan]

I am having the same problem again. When server tries to send mail, citserv is using 102% of CPU.

Citadel documentation says:

citserver crashes (when running on Debian Linux) when sending out Internet email. Fix?

Edit /etc/nsswitch.conf and turn off the 'db' services if you're not using them. (This problem tends to appear on Debian Linux systems, as well as Debian derivatives such as Ubuntu.)

My nsswitch.conf file contains the following lines:

passwd:  compat
group:  compat
shadow:  compat
hosts:  dns files
networks: files
protocols: db files
services: db files
ethers:  db files
rpc:  db files
netgroup: nis

I removed all "db" leaving only 'files'. Stopped Citadel. Server load dropped to 0.1. Started Citadel. Server load is about 2 again and citserv is using 100% of CPU.

Don't know what to do.

What happends if I stop citadel forever? Can I send mail without involving Citadel?

Thanks.

[lammert]

Citadel is an email/groupware server solution. It is used to let people collaborate with each other, a little bit like Microsoft Exchange or Open Groupware. It can also act as a kind of forum.

If you stop Citadel, basic email delivery still works, but options like webmail, address books etc won't work anymore.