You could setup DRBD between the two servers to host the VM images and configuration files.
I believe this setup will allow for live migration between the two hosts. If not it should allow you to just start a VM up on either server should one go down. This could be automated a bit by using heartbeat to run some scripts to restart the VM's should one of the hosts go down. This article seems to do this with live migration and LVM.
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
Best Answer
Received much better information from the commandline:
# xe vm-start vm='vmDoesNotStart' This operation cannot be performed because the specified VDI could not be found on the storage substrate sr: 34aabadd-ea86-ac22-2f3e-51fdadf41ebb (XenServer Tools) vdi: cdac77c7-011b-4184-8a47-361b6335d2e2 (Old version of xs-tools.iso)
Clicking eject next to 'DVD Drive 1:' fixed this and the servers start up. So turns out it had nothing to do with the "harddisks" but just "optical discs."