2718.us blog » email

Converting from Maildir to mbox Files

2718.us — Tue, 29 Sep 2009 02:20:40 +0000

A slight misconfiguration had SpamAssassin dropping spam into ~/Maildir/.spam/ while Dovecot was looking for mbox files in ~/mail/. From my initial bit of Googling, I was expecting to have to download some program to do the heavy lifting. Luckily, I came across a very simple blog post with a very simple answer that worked like a charm.

Need to generate an mbox out of a Maildir mailbox? Formail helps:
cd $MAILDIR/cur
for i in * ; do cat $i | formail -c >> $MBOXFILE ; done

Input Validation: Check your RFCs

2718.us — Thu, 01 May 2008 16:31:33 +0000

Most drop-in “is this a valid-form email?” functions do label certain valid email addresses as invalid. In particular, while highly unlikely, it is valid to have an email address at a TLD. Why did this come to mind? Very circuitously. I was watching YouTube videos when I noticed that it was loading stuff from “i.ytimg.com,” which is NOT a valid FQDN. Each part of a FQDN must be at least two characters, with the special exception of the root nameservers. While nearly everyone and everything handles single-character hostnames nowadays, there have been and probably still are some servers that choke on single-character hostnames (I know that I’ve had issues with email addresses with single-character hostnames).

By the way, the combination of these two things means that the shortest email address that will validate in (nearly) all format-validation routines is a single character at a two-character SLD under a two-character coutry-code TLD, such as “a@te.st”.

Web Hosting

2718.us — Fri, 11 Apr 2008 21:25:12 +0000

… or “How I learned to stop worrying and just sell my friends hosting.”

I have many friends who aren’t particularly techie types. Actually, I have very few techie friends. And they all figure I’m the go-to guy for their tech questions. Hence, I get asked to “help out” with setting up web sites now and then.

At some point, it occurred to me that, while there were plenty of good vendors I could recommend to peope (I’ll even give a list of some below), if I suggested that a friend use one or more of these vendors, the friend would inevitably still have questions that were vague and not really tech-support questions, and they’d end up back asking me for help. It’s much easier to help them if I don’t have to go digging through some hosting company’s control panel to find the one messed up setting that I could have fixed in 2 seconds with a command line…

So I should just provide these people with hosting. This is how I entered the world of small, in some sense “boutique,” hosting. I’m not a company with credit card processing and automated account setup and 24-7 tech support. These aren’t mission-critical sites. When I’m asked, “How do I go about setting up a web site for [X]?” I can explain the overall steps (get a domain name; get hosting; if these are separate, point name at host; make web pages; upload web pages), I can recommend commercial providers (list below), and I can add that while I can honestly recommend those vendors, I can also offer to deal with all the setup and hosting to the point where they have some control panel and can figure out page creation and uploading, and I’ll charge them something or other that we mutually agree is fair.

When things break, I can fix them on the server easily. If they’re unhappy, I can help them move off to a commercial provider. And, hopefully, what they pay me defrays the costs of the servers I’m already running my sites on.

Oh, and as a side note, unless you’re doing something fancy or getting a lot of traffic on your site, there is no reason to be paying more than about $1/month for hosting, and contracts longer than a year are probably a bad idea (except where the monthlies are so small as to make month-to-month impractical, say maybe under $5/month, or where there’s a deep discount for longer contracts, I strongly prefer month-to-month payment rather than yearly contracts).

Vendors I currently use:

WorldWideDNS.net (DNS)
No-IP.com (dynamic IP)
RapidVPS.com (hosting)
GoDaddy.com (domain names, SSL certs)
LuxSci.com (email)

Vendors I have used in the past and think are generally good:

ucvhost.com (hosting)
No-IP.com (DNS, email)
5dollarhosting.com (hosting)
hostrocket.com (hosting)
fusemail.com (email)
cheap-domainregistration.com (domain names)