After an upgrade of my webserver from 12.04.5 LTS to 16.04.2 LTS, my webserver no longer worked and I was forced to reinstall the server.
Unfortunately, I was only able to backup the raw database files from /var/lib/mysql without being able to make .sql backups.
I have reinstalled the server with Ubuntu 16.04.2 LTS and copied the backed up database files into the respective locations, but they do not work. The permissions were set to mysql:mysql - so that is not the problem. On the old system, I had MySQL version 5.5.53 and the new version is now 5.7.19. The system is running with Plesk Onyx 17.5.3 Update #17.
How can I correctly convert my raw MySQL files (*.frm, *.myd, *.myi) to work properly on the upgraded server?
I suspect I have to be able to first convert the old files to .sql format and then import them again on the new server?
I am a beginner with Linux, but do know enough to run command line commands. I often use Midnight Commander for configuration, etc. as well as Plesk.