How can I see what is going on

[Eric Diwouta-Loth]

on the machineat a given time.
I am trying to set up a pop3 server and my problem is that I would like to
see what's goin' on in real time to see how the machine responds to mail
download requests from pop3 clients (running on zindozs95).
I use Sendmail as MTA and I run Suse 5.3
Thanks for any clue