My disk is formatted using GPT. I created a new partition and by default it was create as 'Linux filesystem' (gdisk code 8300).
When I am trying to mount it via fstab
/dev/sda4 /vmguests ext4 errors=remount-ro 0 1
it errors out with
mount: wrong fs type, bad option, bad superblock on /dev/sda4
What would be the right type code for ext4 filesystem in gdisk?
Best Answer
That error message has nothing to do with GPT (or MBR) type codes; it's referring to the filesystem contained within the partition. I suspect you haven't created that filesystem. Many partitioning tools, including
gdisk
, do not create filesystems; they just create the partitions in which filesystems can be created. To create a filesystem, you'd need to use a command like this:You must type that command as
root
or via thesudo
utility, just likegdisk
.Some tools, such as GParted, do both jobs simultaneously, which is convenient but muddies the waters a bit for those learning the system, because it's easy to misunderstand the distinction between partitions and filesystems. Partitions are simple data structures that consist of the starting sector number and the ending sector number (or, equivalently, the length), as well as associated meta-data such as a type code. Filesystems are much more complex data structures that are typically contained within a partition. Filesystems facilitate the creation and manipulation of files -- often thousands of them.
Incidentally, the Linux kernel ignores partition type codes. So do many Linux utilities. Linux partitioning tools support them because they're part of partition table data structures and because some other OSes use type codes as a filter, so it's important that the Linux codes be right in a dual-boot environment. Linux installation programs also often use type codes in a similar way.