Backup¶

Manual¶

You can use the provided script helper-scripts/backup_and_restore.sh to backup mailcow automatically.

Danger

Please do not copy this script to another location.

To run a backup, write "backup" as first parameter and either one or more components to backup as following parameters. You can also use "all" as second parameter to backup all components. Append --delete-days n to delete backups older than n days.

# Syntax:
# ./helper-scripts/backup_and_restore.sh backup (vmail|crypt|redis|rspamd|postfix|mysql|all|--delete-days)

# Backup all, delete backups older than 3 days
./helper-scripts/backup_and_restore.sh backup all --delete-days 3

# Backup vmail, crypt and mysql data, delete backups older than 30 days
./helper-scripts/backup_and_restore.sh backup vmail crypt mysql --delete-days 30

# Backup vmail
./helper-scripts/backup_and_restore.sh backup vmail

Variables for backup/restore script¶

Multithreading¶

With the 2022-10 update it is possible to run the script with multithreading support. This can be used for backups as well as for restores.

To start the backup/restore with multithreading you have to add THREADS as an environment variable in front of the command to execute the script.

THREADS=14 /opt/mailcow-dockerized/helper-scripts/backup_and_restore.sh backup all

The number after the = character indicates the number of threads. Please keep your core count -2 to leave enough CPU power for mailcow itself.

Backup path¶

The script will ask you for a backup location. Inside of this location it will create folders in the format "mailcow_DATE". You should not rename those folders to not break the restore process.

To run a backup unattended, define MAILCOW_BACKUP_LOCATION as environment variable before starting the script:

MAILCOW_BACKUP_LOCATION=/opt/backup /opt/mailcow-dockerized/helper-scripts/backup_and_restore.sh backup all

Tip

Both variables mentioned above can also be combined! Ex:
```
MAILCOW_BACKUP_LOCATION=/opt/backup THREADS=14 /opt/mailcow-dockerized/helper-scripts/backup_and_restore.sh backup all
```

Cronjob¶

You can run the backup script regularly via cronjob. Make sure BACKUP_LOCATION exists:

PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
5 4 * * * cd /opt/mailcow-dockerized/; MAILCOW_BACKUP_LOCATION=/mnt/mailcow_backups /opt/mailcow-dockerized/helper-scripts/backup_and_restore.sh backup mysql crypt redis --delete-days 3

Per default cron sends the full result of each backup operation by email. If you want cron to only mail on error (non-zero exit code) you may want to use the following snippet. Pathes need to be modified according to your setup (this script is a user contribution).

This following script may be placed in /etc/cron.daily/mailcow-backup - do not forget to mark it as executable via chmod +x:

#!/bin/sh

# Backup mailcow data
# https://docs.mailcow.email/backup_restore/b_n_r-backup/

set -e

OUT="$(mktemp)"
export MAILCOW_BACKUP_LOCATION="/opt/backup"
SCRIPT="/opt/mailcow-dockerized/helper-scripts/backup_and_restore.sh"
PARAMETERS="backup all"
OPTIONS="--delete-days 30"

# run command
set +e
"${SCRIPT}" ${PARAMETERS} ${OPTIONS} 2>&1 > "$OUT"
RESULT=$?

if [ $RESULT -ne 0 ]
    then
            echo "${SCRIPT} ${PARAMETERS} ${OPTIONS} encounters an error:"
            echo "RESULT=$RESULT"
            echo "STDOUT / STDERR:"
            cat "$OUT"
fi

Backup strategy with rsync and mailcow backup script¶

Create the destination directory for mailcows helper script:

mkdir -p /external_share/backups/backup_script

Create cronjobs:

PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
25 1 * * * rsync -aH --delete /opt/mailcow-dockerized /external_share/backups/mailcow-dockerized
40 2 * * * rsync -aH --delete /var/lib/docker/volumes /external_share/backups/var_lib_docker_volumes
5 4 * * * cd /opt/mailcow-dockerized/; BACKUP_LOCATION=/external_share/backups/backup_script /opt/mailcow-dockerized/helper-scripts/backup_and_restore.sh backup mysql crypt redis --delete-days 3
# If you want to, use the acl util to backup permissions of some/all folders/files: getfacl -Rn /path

On the destination (in this case /external_share/backups) you may want to have snapshot capabilities (ZFS, Btrfs etc.). Snapshot daily and keep for n days for a consistent backup. Do not rsync to a Samba share, you need to keep the correct permissions!

To restore you'd simply need to run rsync the other way round and restart Docker to re-read the volumes. Run:

docker compose (Plugin)docker-compose (Standalone)

docker compose pull
docker compose up -d

docker-compose pull
docker-compose up -d

If you are lucky Redis and MariaDB can automatically fix the inconsistent databases (if they are inconsistent). In case of a corrupted database you'd need to use the helper script to restore the inconsistent elements. If a restore fails, try to extract the backups and copy the files back manually. Keep the file permissions!