How to make sendmail write to new maillog

Question

I want to rotate my maillog, but I want to make sure the newly rotated log contains the last 2M lines from the previous log:

    # write the last 2M lines to a new log
    tail -n 2000000 /var/log/maillog > /var/log/maillog.new

    # move the existing log to datestamped backup
    datestamp=`date "+%Y%m%d"`
    mv /var/log/maillog /var/log/maillog.$datestamp

    # move the new log to normal log
    mv /var/log/maillog.new /var/log/maillog

    # tell sendmail to reload
    killall -HUP sendmail

This all works, except for the fact that sendmail continues to write to the backup log file "maillog.yyyymmdd" instead of the proper "maillog"!

What is the correct way to do this without having to stop sendmail first, rotate, then start again?

Answer 1

Usually maillog written by syslogd, not by sendmail itself, so you should send SIGHUP to syslogd