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