Backup, Restore & Merge

It’s a good idea to take periodic backups of the bitmagnet database. A system crash might corrupt the database, in which case you could see the dreaded PANIC: could not locate a valid checkpoint record when starting Postgres.

Perhaps you’d like to move your bitmagnet installation to a new server, or you’d like to merge the data from two bitmagnet installations.

This tutorial will show you how to backup, restore and merge bitmagnet databases.

Pre-requisites

• You’ll need to have pg_dump and psql installed. These are part of the PostgreSQL package. Use Google to find out how to install these tools on your operating system.

Taking a backup

If you intend to import your backup to another bitmagnet instance, you should ensure the other instance is the same version. If the other instance is already a higher version, you’ll need to upgrade the instance you’re backing up from before taking a backup.

The following command will take a backup of the critical bitmagnet data and save it to a file named export.sql. (note this is not a full backup of the database which would include creation of tables, indexes etc.). By exporting with the --data-only flag the resulting file can be imported into a new or existing installation, after bitmagnet has run its migrations to set up the database and tables.

Please refer to the pg_dump documentation and ensure to specify the correct values (e.g. host, username and password) for the source database.

pg_dump \
        --column-inserts \
        --data-only \
        --on-conflict-do-nothing \
        --rows-per-insert=1000 \
        --table=metadata_sources \
        --table=content \
        --table=content_attributes \
        --table=content_collections \
        --table=content_collections_content \
        --table=torrent_sources \
        --table=torrents \
        --table=torrent_files \
        --table=torrent_hints \
        --table=torrent_contents \
        --table=torrent_tags \
        --table=torrents_torrent_sources \
        --table=key_values \
        bitmagnet \
        > backup.sql

Restoring a backup, or merging into another bitmagnet instance

First, ensure you have a target bitmagnet instance up and running, of the same version from which the backup was taken.

The following command will import the backup file into the target database, merging the data with any existing data.

Please refer to the psql documentation and ensure to specify the correct values (e.g. host, username and password) for the target database.

psql bitmagnet < backup.sql