There may be times you log in to the WHM or your servers command-line interface and try to restart MySQL. However, MySQL reports MySQL fails to start: Errcode: 30 - Read-only file system.
When trying to start a service, you receive an error reporting the file system is in read-only.
You will need to remount the drive to allow read and write. You can check this with mount and then remount with
mount -o remount,rw <partition>