If you see a large mail queue and your system's I/O is increasing, you may find messages like these in your syslog:
Losing q5/qfg9N5EwE3004499: savemail panic
SYSERR(root): savemail: cannot save rejected email anywhere
In this situation, there's some reason why sendmail cannot deliver e-mail to the postmaster address. There's a few issues that can create this problem:
- Missing postmaster alias in /etc/aliases
- Hard disk is full
- The mail spool for the postmaster has the wrong ownership
- The mbox file for the postmaster is over 2GB and procmail can't deliver the e-mail
First, correct the situation that is preventing sendmail from delivering the e-mail to the postmaster user. Then, stop sendmail, clear the e-mail queue, and start sendmail again.
I found this issue on a Red Hat Enterprise Linux 4 server and then found the solution on Brandon's site.
