Dovecot (for mail archive)

Dovecot configured with one user (app), great for archiving mails.

As it is supposed (for now at least) to be accessed locally or via a ssh tunnel, SSL/TLS is not used.

Usage

docker run --rm --name mailarchive -e MBOXFORMAT=mdbox -e "MAILPASSWORD={SHA512-CRYPT}$6$/LQkGPokW$Htf33uIYq6x9o7XCiVhNbA7IM4cjWjSAnY/tJyroy.suypFnIFkq2S3EnZV0pjbCh41.sLGsbljcNb0C3ZFH9/" -v ./storage:/home/app ajoergensen/dovecot-mailarchive

Environment

MAIL_PASSWORD: The password to use for logging into the IMAP4 server as user app
MBOXFORMAT: The format to store the mails in, defaults to Maildir

Password

A note on the password. If you supply a clear text password it will be encrypted before adding it to the user database, but it will be available in clear text form in the container's environment.

I recommend using the encrypted form of the password in the environment.

If you want to copy the password string from an existing account, use this mapping for MAIL_PASSWORD:

If the string starts with $6$ , use {SHA512-CRYPT}$6$existinghash
If the string starts with $5$ , use {SHA256-CRYPT}$5$existinghash
If the string starts with $1$ , use {MD5-CRYPT}$1$existinghash (or better yet, generate a new hash as MD5 is considered weak)

To create an encrypted password string, enter the container with docker exec -it dovecot bash and run

bash-4.3# doveadm pw -s BLF-CRYPT

This will prompt for a password and return the hash.

For more information about supported password schemes, go to Dovecot's documentation

Mailbox formats

Dovecot supports various mailbox formats, I've chosen to support Maildir and dbox (the container will fail if you chose something else).

maildir: Maildir format. Mails are stored in /home/app/Maildir
sdbox: Dbox format, one message per file. Mails are stored in /home/app/dbox
mdbox: Dbox format, multiple messages per file. Mails are stored in /home/app/dbox

Volumes