If you see the error message:

fsck does not want to work because /dev/md0 is in use

and the boot process drops to a shell, your drives will be mounted as read-only. In order to mount them so you can write to them you can remount the filesystem in read/write mode with:

sudo mount -o remount,rw /

You could try also unmounting the drives and running fsck manually on them:

umount /
fsck /dev/md0

Then, if everything is OK, reboot.

• Trouble Booting Related to Hard Disk Errors

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