13.5.2. Virtual Storage Devices

13.5.2. Virtual Storage Devices

Perform the following steps to configure additional virtual storage devices for your guest.

Edit your guest configuration file in /etc/xen/YourGuestName replacing YourGuestName with the name of your guest. The original entry may look like the one below.

disk = [ "file:/var/lib/xen/images/rhel5_64_fv.dsk,hda,w"]

Add an additional entry for your new physical device, LUN, partition or volume to the “disk=” section of the configuration file. The storage entity the para-virtualized driver the updated entry would like the following. Note the use of “tap:aio” for the para-virtualized device if a file based image is used.

disk = [ "file:/var/lib/xen/images/rhel5_64_fv.dsk,hda,w",
    "tap:aio:/var/lib/xen/images/UserStorage1.dsk,xvda,w" ]

If you want to add more entries just add them to the “disk=” section as a comma separated list.


You need to increment the letter for the 'xvd' device, that is for your second storage entity it would be 'xvdb' instead of 'xvda'.

disk = [ "file:/var/lib/xen/images/rhel5_64_fv.dsk,hda,w",
    "tap:aio:/var/lib/xen/images/UserStorage1.dsk,xvda,w" ] 
    "tap:aio:/var/lib/xen/images/UserStorage2.dsk,xvdb,w" ]

Verify the partitions have been created and are available.

# cat /proc/partitions
major minor  #blocks    name
   3     0   10485760   hda
   3     1     104391   hda1
   3     2   10377990   hda2
 202     0      64000   xvda
 202     1      64000   xvdb
 253     0    8257536   dm-0
 253     1    2031616   dm-1

In the above output you can see the partition or device “xvdb” is available to the system.

Mount the new devices and disks to local mount points and update the /etc/fstab inside the guest to mount the devices and partitions at boot time.

# mkdir /mnt/pvdisk_xvda
# mkdir /mnt/pvdisk_xvdb
# mount /dev/xvda /mnt/pvdisk_xvda
# mount /dev/xvdb /mnt/pvdisk_xvdb
# df /mnt/pvdisk_p1
Filesystem           1K-blocks      Used   Available Use%  Mounted on
/dev/xvda                64000        15       63985   1%  /mnt/pvdisk_xvda
/dev/xvdb                64000        15       63985   1%  /mnt/pvdisk_xvdb

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