Mastodon restore from backup fails - Could not find 'bundler'

To be honest, the best thing would be to do a new installation on its own.

Via SSH
Create folder to put backups

Ex:

mkdir /var/www/backups/mastodon_backup

BACKUP :floppy_disk: :

cd /var/www/mastodon/live
pg_dump -U mastodon -W -F t mastodon > /var/www/backups/mastodon_backup/mastodon_backup.dump

RESTORE :hammer_and_wrench::

cd /var/www/mastodon/live
pg_restore -U mastodon -d mastodon < /var/www/backups/mastodon_backup/mastodon_backup.dump

Here’s another example of backup.

Then make a new installation