[CentOS] Assign external esata drive to KVM

Sat Oct 20 16:39:00 UTC 2012
Kanwar Ranbir Sandhu <m3freak at thesandhufamily.ca>

Hello Everyone,

I have a CentOS 6.3 host running a few KVMs.  One of them is a CentOS
6.3 KVM that I want to use for making backups with BackupPC.  What I'm
having a problem with is assigning the KVM an external drive.

I used to run BackupPC on an Ubuntu box. The backups went to an external
eSATA 1.5TB, ext4 format, single partition drive (regular 3.5" in an
enclosure).  I want to now attach that same external drive to my KVM
host, and pass it up to the KVM running BackupPC.

I added the entire drive as a second storage disk to the KVM. I used the
disk's label (/dev/disk/by-label/backups) so that I wouldn't have to
worry about the device name changing down the road.  When I booted up
the KVM and listed the disks, I only saw "/dev/vdb". I was also
expecting to see "/dev/vdb1".

I ran fdisk on it only to see the partition table wasn't detected.  The
drive itself is OK - I can mount it successfully on the KVM host.
Here's the fdisk output:

Device contains neither a valid DOS partition table, nor Sun, SGI or OSF
Building a new DOS disklabel with disk identifier 0xd6912a1b.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won't be recoverable.

Warning: invalid flag 0x0000 of partition table 4 will be corrected by

WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
         switch off the mode (command 'c') and change display units to
         sectors (command 'u').

Command (m for help): p

Disk /dev/vdb: 1500.3 GB, 1500300861440 bytes
16 heads, 63 sectors/track, 2907018 cylinders
Units = cylinders of 1008 * 512 = 516096 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xd6912a1b

   Device Boot      Start         End      Blocks   Id  System

Command (m for help): quit

So...how do I properly assign this eSATA disk to the KVM?  FYI: the
enclosure can use USB as well.



Kanwar Ranbir Sandhu
Linux 3.5.4-2.fc17.x86_64 x86_64 GNU/Linux 
12:20:20 up 12 days, 37 min, 3 users, load average: 0.09, 0.09, 0.12