2012/10/20 Kanwar Ranbir Sandhu m3freak@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 disklabel 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 w(rite)
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.
Thanks,
Ranbir
Hi Ranbir, please post the relevant configuration items from the guest's xml definition and the output of fdisk when done on the host.