while running below artisan command from controller works fine
Artisan::call('backup:run');
but why this is not working
Artisan::call('backup:run --only-db');
it throws error The command "backup:run --only-db" does not exist.
through CLI it works fine
php artisan backup:db --only-db
I believe what you wanted to do is.
Artisan::call('backup:run',['--only-db'=>true]);