Hey,
I taked many times to find how migrate our nice Flarum install. That's how we do it:
Backup your DB on the ancient host:
mysqldump --lock-tables -h [server] -u [user] -p[password] [database] > flarum-sqlbkp_`date +"%Y%m%d"`.bak
Backup your data on the ancient host:
rsync -Aax flarum/ flarum-dirbkp_`date +"%Y%m%d"`/
Download all of this on your new host:
scp -r user@host.lol:flarum-* .
Create new DB:
mysql -u root -p CREATE DATABASE flarum; exit
Restore old DB on da new:
mysql -h [server] -u [username] -p[password] [db_name] < flarum-sqlbkp.bak
Do a fresh install of flarum as described here: http://flarum.org/docs/installation/
Restore some of the old data on your new installation:
cd flarum-dirbkp/ cp -Rv config.php storage/ assets/ /var/www/fresh-new-flarum/
Reinstall your extensions and it's done !
Hope this little tutorial will help some folks.
Cheers,