The email server for AMANDA at UW-Madison is called mxamanda.physics.wisc.edu. What you've never heard of this machine? Well that is because it is better known as white.physics.wisc.edu. How does an email addressed to my local computer, ocher.physics.wisc.edu for example, get to white? This is a bit of DNS black magic called an MX record. All our local machines have a DNS record called an MX record (no not an MX Connector!), which points to mxamanda. So a sendmail transport agent looks up ocher, sees the MX record, and knows to send it to mxmanda. You can have more than one MX record, with different priorities. Very handy for load balancing. But we only have one. We use the name mxamanda becuase if white failed, we just have to make one change to the DNS to redirect all our mail. Plus the name is a bit more informative.
So that is how the email gets to the server. The next step is procmail, which puts the email in your email box on the server. If you want fancy things to happen to your email, you can add a .procmailrc file in your home directory. Here is what the user data's fiel looks like.
# more ~data/.procmailrc SHELL=/bin/sh MAILDIR=/data/amanda/2002/emails LOGFILE=/home/data/log/procmail.log :0B * ^.*Climate Summary | /home/data/bin/MET-mail-filter.pl :0B * ^.*SPTR MCS Status Report | /home/data/bin/SPTR-mail-filter.pl :0 * ^Subject:.*DailyData | /home/data/bin/SPDATA-mail-filter.pl :0 * ^Subject: Warning: could not send message /dev/null
To read your email you use a user agent such as pine, netscape, or vm on xemacs (maybe rm on emacs?). How does the user agent get the mail? Traditionally we've exported the /var/spool/mail directory, and the user agents just use movemail. While this is simple, it has problems. So we are moving towards using IMAP (Internet Message Access Protocol). How do I use IMAP?
