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3.14 Restore from backup ¶

If you have a recent backup, this path is faster than installing from scratch.

1. Provision a fresh Ubuntu 24.04 host.
2. Install just enough packages to extract and restore:

   sudo apt update
   sudo apt install -y openjdk-21-jdk-headless \
       postgresql-16 postgresql-16-pgvector \
       s3fs gzip tar
   

3. Mount the backup bucket. You will need the AWS credentials by other means (password manager, etc.) since /etc/passwd-s3fs is itself inside the backup:

   sudo mkdir -p /mnt/backups
   echo "<bucket>:<KEY>:<SECRET>" | sudo tee /etc/passwd-s3fs
   sudo chmod 600 /etc/passwd-s3fs
   sudo s3fs <bucket> /mnt/backups -o passwd_file=/etc/passwd-s3fs \
       -o allow_other -o use_path_request_style
   

4. (optional) Reinstall previously-managed apt packages:

   sudo tar -xzf /mnt/backups/files-YYYY-MM-DD.tar.gz -C /tmp \
       var/lib/ownsona-backup/apt-mark-manual.txt
   xargs -a /tmp/var/lib/ownsona-backup/apt-mark-manual.txt sudo apt install -y
   

5. Extract the file backup over the root filesystem:

   sudo tar -xzpf /mnt/backups/files-YYYY-MM-DD.tar.gz -C /
   

   This restores /home, /root, /etc, /usr/local, /opt, the per-user crontabs in /var/spool/cron, the live systemd units, and the metadata bundle.

6. Restore PostgreSQL (drops and recreates everything):

   zcat /mnt/backups/database-YYYY-MM-DD.gz | sudo -u postgres psql -X postgres
   

7. Reload systemd and bring services up:

   sudo systemctl daemon-reload
   sudo systemctl enable --now ownsona.service
   sudo systemctl enable --now ownsona-backup.timer
   

8. Smoke test (see Smoke test).

The OS-level ownsona Linux user is restored along with /home/ownsona, so no manual adduser is needed. PostgreSQL roles (including the ownsona role and its password hash) are restored by pg_dumpall.