SMM:08-14
Sendmail Installation and Operation Guide
Figure 1 -- A complex startup script
work:
# stop & start sendmail
PIDFILE=/var/run/sendmail.pid
kill `head -1 $PIDFILE`
`tail -1 $PIDFILE`
because it assumes that the pidfile will still exist even after killing the process to which it refers.
Below is a script which will work correctly on both newer and older versions:
# stop & start sendmail
PIDFILE=/var/run/sendmail.pid
pid=`head -1 $PIDFILE`
cmd=`tail -1 $PIDFILE`
kill $pid
$cmd
This is just an example script, it does not perform any error checks, e.g., whether the pidfile
exists at all.
1.3.16. Map Files
To prevent local denial of service attacks as explained in the top level README in the
sendmail distribution, the permissions of map files created by makemap should be 0640. The
use of 0640 implies that only trusted users belong to the group assigned to those files. If those
files already exist, then it might be necessary to change the permissions accordingly, e.g.,
cd /etc/mail
chmod 0640 *.db *.pag *.dir
2. NORMAL OPERATIONS
2.1. The System Log
The system log is supported by the syslogd (8) program. All messages from sendmail are
logged under the
LOG_MAIL
facility
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.
2.1.1. Format
Each line in the system log consists of a timestamp, the name of the machine that gener-
ated it (for logging from several machines over the local area network), the word "sendmail:",
and a message
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. Most messages are a sequence of name=value pairs.
The two most common lines are logged when a message is processed. The first logs the
receipt of a message; there will be exactly one of these per message. Some fields may be omit-
ted if they do not contain interesting information. Fields are:
from
The envelope sender address.
size
The size of the message in bytes.
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Except on Ultrix, which does not support facilities in the syslog.
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This format may vary slightly if your vendor has changed the syntax.