ajoergensen/dovecot-mailarchive repository overview

⁠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

• /home/app: The app user's home directory, used to store the mail