What if gmail went away tomorrow, or at least deleted all your mail? It may not be as far fetched as you think. It's always prudent to have a backup.
Installing and configuring getmail is simple.
sudo apt-get install getmail # decide where you want you mail to live, and create an empty file there touch ~/Dropbox/backup/gmail.mbox mkdir ~/.getmail vim ~/.getmail/getmailrc # add the following [retriever] type = SimpleIMAPSSLRetriever server = imap.gmail.com username = YOURGMAILADDRESS password = YOUGMAILPASSWORD mailboxes = ("[Gmail]/All Mail",) [destination] type = Mboxrd path = ~/Dropbox/backup/gmail.mbox [options] read_all = False # just get the new messages on subsequent runs message_log_syslog = True
You can test whether your configuration working by running getmail manually from the command line. The initial download can take a while to begin if you have thousands of messages. The actual download will likewise take a long time for large mailboxes. While it's in progress, you will get a series of log messages on the console (and in syslog).
getmail ... several minutes later ... SimpleIMAPSSLRetriever:email@example.com@imap.gmail.com:993: msg 1/105702 (325 bytes) delivered msg 2/105702 (335 bytes) delivered msg 3/105702 (363 bytes) delivered msg 4/105702 (180479 bytes) delivered msg 5/105702 (311 bytes) delivered msg 6/105702 (1057 bytes) delivered msg 7/105702 (818 bytes) delivered msg 8/105702 (331 bytes) delivered msg 9/105702 (321 bytes) delivered msg 10/105702 (882 bytes) delivered msg 11/105702 (1201 bytes) delivered msg 12/105702 (1614 bytes) delivered msg 13/105702 (359 bytes) delivered msg 14/105702 (359 bytes) delivered ...
I choose to configure getmail to use a single mbox file, but you can also use one file per message. In addition to this large file, getmail will keep a smaller index file in ~/.getmail.
If you want, you can setup a cron job to update your backup nightly.
crontab -e # add the following line, which will run the backup at 1AM every day * 1 * * * /usr/bin/getmail >/dev/null 2>&1