If you have access to two machines, kill the sendmail daemon
on one, then send mail to that machine from the other using the
-v (verbose) switch. What does this tell you
about why it is important to always re\%start the daemon after
you have killed it? How can you tell that a remote sendmail
daemon has died?
-v switch, send mail
to yourself. In the message body, include nothing but lines
that begin with dots. Does the message get through intact?
Begin forming the habit of routinely running mailq several times per day. Start to learn the many reasons that mail is queued rather than sent.
Write a shell script that runs sendmail with the
(verify) switch to determine whether every alias in the aliases(5)
file is good and print those that aren't.
Be sure to filter the output so that good addresses (those
deliverable) are not printed.
Read the online manuals for all the MUAs
on your system, such as that for /usr/ucb/Mail. For which
MUAs is it possible to indirectly run sendmail in verbose mode?
That is, which will pass a
-v command-line switch through