Partial restoration

This is necessary if you lost a specific email, or if you want to go back in time, and restore a bunch of emails you inadvertently deleted.

At this time, the partial restoration is manual and can be done only by root. An easier option to retrieve emails from backups will be provided in a future version. In the mean time, the process has to be manual:

  1. Connect on the server, using SSH, as root.
  2. Load the backup encryption key into your environment.
  3. List the backups snapshots, using borg list command
  4. Mount the backup snapshot you are interested in, they are listed by date. You can do this by using the borg mount command
  5. Search in the mounted drive for the lost emails, using for instance the excellent midnight commander.
  6. Copy the emails at the place of your choice, perhaps in your /home/users//mails/maildir/ folder to make them accessible from an email client.
  7. Make sure the copied email files belongs to the right user, otherwise Dovecot won’t be able to read these files. belongs to the right user.
  8. The last thing to do, before disconnecting, is to ‘unmount’ the backup snapshot, using the borg umount command
  9. Finally, disconnect from SSH.
  10. Open your email client.

Data restoration

Something bad happened, for instance you just deleted a lot of email, contacts or calendar events. In this case, before the next backup occurs and backup your mistake, you can quickly restore your emails, calendar events and contacts, with just one line.

So, just run the main borgbackup installation script:

cd install
ansible-playbook -v -i ../config/hosts.yml -t restore playbooks/borgbackup.yml

Note

This step restores all the emails from the last backup. It does not restore your emails from a “previous” state. Therefore, it does not delete any emails that have been created after the backup. The same is happening for calendar events and contacts.

Complete restoration

This is the disaster recovery option.

Something really bad happened, and you lost your box. Don’t panic, if you have installed the system properly, you can easily restore it from scratch, with the all your users’ data. This is done by adding one line in your sysetm.yml file!

The important thing is to have kept the deployment backup folder in a safe place, for instance on an encrypted USB drive.

Let’s say you have used Amazon S3 for the daily backup of your system. So, open your system.yml file with your favourite editor, and add the line restore: true to the backup location you want to restore from. For instance:

backup:
  install: true
  alerts:
    from: 'postmaster@casimir.fx'
    recipient: 'hendrick@universiteitleiden.nl'
    jabber: true
  locations:
  - name: s3main
    restore: true
    url: s3fs://mnt/backup/s3main/casimir.fx
    active: yes
    frequency: daily
    keep_daily: 7
    keep_weekly: 4
    keep_monthly: 6
    access_key_id: AKIAM2HEGKRL50SDZTTC
    secret_access_key: MpHag/11PUXRVIDSKMV8YQZZDW95IGDV
    bucket_name: casimir.fx
    region: eu-west-2
    check_frequency: weekly

Now, run the main installation script, to completely reinstall the system. For instance:

cd install
ansible-playbook -v -i ../config/hosts.yml playbooks/main.yml

Depending on the amount of data, the network speed and computer power, the whole installation is taking enough time for you to have a well deserved break. Prepare yourself a nice cup of tea or coffee. Once installed, you should have all your emails from the last backup restored.

Tip

You can perfectly restore from multiple location, by adding the line restore: true to each backup location. In this case, the data will be merged, so you won’t have duplicate emails, calendar events or contacts.

Note

In this example, an email and a Jabber message are sent after the system has been restored.