Restoring from the backup drive, from the shell or from the Restore tab in Emoncms. The tab gathers the three recovery paths: the backup drive, an uploaded .tar.gz archive, and an old emonSD card in a USB reader. Restoring from the drive or the SD card needs a confirmation box ticked.
emoncms-import.sh reads a .tar.gz archive and cannot read the drive mirror. Restoring uses drive-restore.sh:
./drive-restore.sh --list # show the snapshots on the drive
./drive-restore.sh # restore the newest, asks you to confirm
./drive-restore.sh --sql <name> # restore a specific snapshot
./drive-restore.sh --dry-run # report what would be done, change nothing
./drive-restore.sh --delete # also remove feed files not in the backup
It stops the Emoncms services, imports the chosen MYSQL snapshot, copies the feed data back, restores emonhub.conf, flushes redis and restarts everything.
The Restore points card on the Backup tab lists the same snapshots, and Restore from drive on the Restore tab restores the newest.
Before overwriting anything it dumps the current database to backup_location as pre-restore-<date>.sql.gz. A restore started by mistake can be undone with:
gunzip -c <backup_location>/pre-restore-<date>.sql.gz | mysql -u<user> -p <database>
Feed data is overwritten in place and is not covered by that safety net.
settings.ini and settings.php are held in the backup for reference and are not restored. They hold the database credentials and paths of the system the backup was taken from.
Feed files present on this system but absent from the backup are left alone by default. Pass --delete to make this system an exact mirror of the backup. --delete acts on this system only. Nothing is removed from the drive.
The restore refuses to run without --yes when it is not attached to a terminal, so a cron job or a stray script cannot destroy data. The Emoncms interface passes --yes after its own confirmation.
The lock file is shared with drive-backup.sh, so a backup and a restore never run at the same time.
Upload the .tar.gz on the Restore tab. The browser upload can fail for a large archive. In that case copy the file to the backup_source_path directory named in config.cfg and run:
./emoncms-import.sh