How to use more than 3 virtual disks in Linux using CentOS and XenServer

Solution 1:

Same problem here. I think you will see error message in /var/log/messages

blkfront: your disk configuration is incorrect, please use an xvd device instead

Disks in GUI are /dev/hda, /dev/hdb, /dev/hdc, but on RHEL < 6 it is /dev/xvda/ etc... Disk can be added manually from cli, if you name it as /dev/xvd .

Found this: http://forums.citrix.com/message.jspa?messageID=1692261 Check Albert Czarnecki answeres.

"As like I said your machine is running in HVM mode. You must run command and change from HVM to PV: xe vm-param-set uuid=your_machine PV-bootloader=pygrub HVM-boot-policy="" and then run again machine."

Check also https://www.linuxnet.ch/xenserver-howto-convert-hvm-to-pv-rhelsuse/

Edit: I tried that, and now all disks are visible and system is PV .

Quick summary (may vary):

xe vm-list name-label=SERVERNAME params=uuid 
uuid ( RO)    : 2a596adf-ccf4-6469-cf89-702d723cfbb9

UUID=`xe vm-list name-label=SERVERNAME params=uuid | cut -d ":" -f 2`

Check if PV or HVM

xe vm-param-list uuid=2a596adf-ccf4-6469-cf89-702d723cfbb9 | egrep "PV-bootloader|HVM-boot-policy"
xe vm-param-list uuid=`echo ${UUID}` | egrep "PV-bootloader|HVM-boot-policy"
HVM-boot-policy ( RW): BIOS order
PV-bootloader ( RW): 
PV-bootloader-args ( RW):

Set PV:

xe vm-param-set uuid=2a596adf-ccf4-6469-cf89-702d723cfbb9 PV-bootloader=pygrub HVM-boot-policy=""
xe vm-param-set uuid=`echo ${UUID}` PV-bootloader=pygrub HVM-boot-policy=""

After reboot:

fdisk -l 2>/dev/null | grep xvd
Disk /dev/xvdb: 51.5 GB, 51539607552 bytes
Disk /dev/xvde: 1073 MB, 1073741824 bytes   <------ YEAAAAAH "test disk 1GB visible for os"
Disk /dev/xvda: 16.1 GB, 16106127360 bytes
/dev/xvda1   *           1          13      102400   83  Linux
/dev/xvda2              13         274     2097152   82  Linux swap / Solaris
/dev/xvda3             274        1959    13528064   8e  Linux LVM
Disk /dev/xvdc: 1073 MB, 1073741824 bytes