[mdlug] Create an XFS file system in freespace

[Raymond McLaughlin]

R. Kannan wrote:
> Hello,
> 
> I want to create an XFS in the freespace available on my hard drive for storing MPEG
> video files created by MythTV. Apparently MythTV does not work well with ReiserFS (Ver3)
> that I have. If I understand correctly to do this, I have to:
> 
> 1) Create a partition using 'cfdisk'. But cfdisk presents a lot of file system types
> (default is Linux? type 82) but not XFS. Which one do I choose?

fdisk, and by extension cfdisk, only deal with "partition types" which 
are defined in the partition table(s). Once defined, partitions can 
actually be "formatted" with any filesystem type, or as swap or other 
"raw" data, or left blank. Linux will talk to any partition type, if it 
understands the file system.

One time, back when I was dual booting, I switched a disk partition from 
NTFS to (I think) ReiserFS just by running mkfs and changing /etc/fstab. 
I  left the partition type as '7' instead of changing it to 83, and 
linux never complained.

Lke wise it's not teribly uncommon for a beginner setting up a system 
to partition a hard drive with (c0fdisk and leave all the partition 
types as 83 (linux), even the swap partition which should be type 82 
(linux swap/SOLARIS). The system will use the swap space, probably 
without complaining.

Windows, on the other hand will ignore any "unknown" partition type, 
which makes it very easy to hide fat or ntfs filesystems just by 
changing the partition type with (linux) fdisk.

I you want to determine the filesystem contained on a given partiton use 
the command: file -s <device>

> 2) Create a file system using 'mkfs -t xfs /dev/sda10' Are there any options that I
> should use?

If the device already contains a file system mkfs my refuse to write a 
new one without the 'force' option:

     mkfs -t xfs -f /dev/sda10
or
     mkfs.xfs -f /dev/sda10

Of course you want to be absolutely sure about your target before 
running mkfs.

I hope this helps
Raymond McLaughlin

> Thanks 
> 
> Raj K