I can understand why nobody commented on the monitor question (I've now got a KVM by the way), but I was most disappointed to only recieve feedback from two people for my request for book suggestions, both saying they don't use books. If anyone else has any ideas, please leave a comment.

Anyway, on to the e-mail. Until this week, I have been using fetchmail to download my e-mails, and then feed them in to Exim. It all worked quite well, although the cpu usage had a constant average of around 10%, and this week, fetchmail started terminating itself when things got busy, ie every few minutes.

So, I replaced fetchmail with getmail (thank you Andrew) - much better. Rather than delivering to an MTA, it delivers to a MDA; no SMTP madness, it just pipes the e-mail into a new process. For my MDA, I nearly went with Postfix, but in the end chose maildrop because the internet told me to.

Maildrop filters use regular expressions, so my 200+ rule whitelist was going to look very messy. I therefore wrote a small wrapper script that pulls all the rules from a nice simple text file, creates a filter file, tests it, and if all is well it swaps it for the live one. At some point I'll put on a web front end, and I'll be well away.

The internet seems to be missing one key fact about maildrop - how to test the syntax of the filter file, without trying to deliver mail. Simple answer:

maildrop .mailfilter.tmp < /dev/null

where .mailfilter.tmp is the filter you want to test. If there is an error, there will be output on STDERR.

I'm still not convinced by the getmail/maildrop combination; getmail is run from a cron job rather than a daemon, and maildrop is run once for every e-mail. That's going to be over 26,000 program loads a day, which seems a bit unnecessary when a daemon could run once, so I might look at writing an integrated solution at some point. Not just yet though - this seems to be working very well, and cpu usage is at a steady 0%! Sounds good enough to me.

I have been making copious amounts of notes on linux for the past few years, and at some point I will put up an bunch of hints, howtos and support scripts. But that will have to wait for some free time :)