Backing up Gmail with Fetchmail

I have had Gmail since 2004.  I didn't really start using it until 2006, however.  I always told myself that I should back up my emails before a disaster occurred.  Well, a disaster didn't occur.  I finally got around to it.

The Fetchmail program seemed like the best choice for this task.  There are plenty of Googleable articles that describe how to get Fetchmail to work with Gmail.  By default, Fetchmail uses the Mbox mailbox format.

I have experience as an email administrator.  I have used Sendmail and Postfix SMTP servers.  I have also used UW-IMAP and Cyrus IMAP servers.  I have seen how different mailbox formats perform under various conditions.  This lead me to shy away from the Mbox mailbox format.  The Mbox format stores your entire mailbox in a single text file.  Back in the older days of the internet, storing all 512kb of email in a single file was not that big of a deal.  That format doesn't scale to the Gmail mailbox size, however.

I previously used the Maildir fomat before.  Although not as efficent as the built in Cyrus IMAP mailbox, it is good enough.  Below is my configuration for backing up Gmail onto my local server.

.fetchmailrc

poll pop.gmail.com

protocol pop3

username "myemail@gmail.com" password "mysecret"

keep ssl

mda "/usr/bin/procmail"

/etc/procmailrc

# Use maildir-style mailbox in user's home directory

#DEFAULT=$HOME/.maildir/

DEFAULT=/var/mail/maildir

/etc/crontab
0    2  * * *   jeff    fetchmail -d0 -k pop.gmail.com 2>/dev/null >/dev/null

With this configuration, fetchmail will download a fixed number of emails every day.  As time goes on, eventually your entire inbox will get backed up.  Also, new messages (that don't get deleted) will be backed up every night.