XenServer - Lost interfaces

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I recently ran in to an issue where in my XenServer test environment i seemed to lose all 4 of the NICs that was in my XenServer and the XenServer host could not be seen in XenCenter.

Looking at it closer when in XSCONSOLE and you looked at the management interface section you would get a message back saying "no interfaces present" and in the CLI if you were to run a xe pif-list you would get a message back saying "Host is still booting".

If you were to also run a ifconfig on the XenServer host would would even get back a list of all eth's, bond, xapi and xebr's.

I found out that running the xe pool-emergency-transition-to-master would resolve this issue. Once you have run this command wait around 30 seconds and then restart the host and it was now able to be seen within XenCenter.

Deleting Multiple VM's from XenCenter

First use excel (or your choice of word editor) and create a list of all your VM's you would like to delete plus the added XE command options

xe vm-uninstall vm=VM1 force=true
xe vm-uninstall vm=VM2 force=true
xe vm-uninstall vm=VM3 force=true
xe vm-uninstall vm=VM4 force=true
xe vm-uninstall vm=VM5 force=true
xe vm-uninstall vm=VM6 force=true
xe vm-uninstall vm=VM7 force=true
xe vm-uninstall vm=VM8 force=true
xe vm-uninstall vm=VM9 force=true

Next open up a putty session to a Xen Host and copy all of the above next directly in to the putty session.

NOTE: Please be aware that the VM names are CaSe Sensitive.

As the text is processed you'll see each VM being delete and you can also view the VM's being deleted in XenCenter as each line of command runs in the putty session.

[root@XENHOST ~]# xe vm-uninstall vm=VM1 force=true
The following items are about to be destroyed
VM : e995f197-5730-9cfc-3491-c2768e02236f (VM1)
All objects destroyed
[root@XENHOST ~]# xe vm-uninstall vm=VM2 force=true
The following items are about to be destroyed
VM : ec6d123d-a3d5-aa11-9439-f4c44927a0fa (VM2)
All objects destroyed

Obviously be double sure that you have the correct list of VM's before you run this command.

VM won't start and now is in a Stuck State

From time to time Vm's can get stuck in a state where you cannot start, shutdown, reboot or even force a reboot or shutdown. When this happens from the console type: xe-toolstack-restart (note that your XenCenter will loose connection when you do this. Nothing will however happen to your running VMs)

Reconnect with XenCenter (or let it reconnect by itself) and you should see your VM no longer in a stuck state