My Ubuntu server has stopped due to a lack of disk space. I deleted some log files which has grown huge very quickly. But df -h still shows I have no space left. When I run du -sh /* I can see that I should have plenty of disk space left after deleting the logs.

I ran lsof +L1 and it brought up two files: /var/log/mail.log and /var/log/mail.err. These are two logs I had deleted. I restarted apache, postfix and mysql (mysql wont restart because of lack of disk space, it think) but still df -h shows no space.