We have noticed a log related to iscsi daemons filling up disk space on a few of our Centos 5 VPSs lately. There have been a few reports of this in other places:

http://www.webhostingtalk.com/archive/index.php/t-1046154.html

It seems after you do a yum or apt-get update past Centos 5.6, this unneeded service will sometimes get enabled:

# chkconfig --list | grep iscsi
iscsi 0:off 1:off 2:off 3:on 4:on 5:on 6:off
iscsid 0:off 1:off 2:off 3:on 4:on 5:on 6:off

If that happens you will need to turn them off:

# chkconfig iscsi off
# chkconfig iscsid off

Or else you will get some meaningless logs filling up your disk space like this:

# tail brcm-iscsi.log
ERR [Tue Jan 31 19:44:24 2012]NIC_NL waiting binding to NETLINK_ISCSI socket
ERR [Tue Jan 31 19:44:25 2012]NIC_NL waiting binding to NETLINK_ISCSI socket
ERR [Tue Jan 31 19:44:26 2012]NIC_NL waiting binding to NETLINK_ISCSI socket
ERR [Tue Jan 31 19:44:27 2012]NIC_NL waiting binding to NETLINK_ISCSI socket
ERR [Tue Jan 31 19:44:28 2012]NIC_NL waiting binding to NETLINK_ISCSI socket

Also be sure to stop those daemons:

# /etc/init.d/iscsid stop
# /etc/init.d/iscsi stop

And be sure to remove the log at:

/var/log/brcm-iscsi.log

To free up some space.

For some more tips on checking what is using up all your disk space check our page here.