MSCS across two ESX Hosts VM's wont start on seperate hosts?

[packetboy]

Hi here is the very long story:

We setup a two node windows 2003 print server cluster however when we first set it up we did it as a cluster in a box. Then we wanted to go into production with it so I got 2 RDM's created. I set them up and added them along with the existing virtual machine disks. I then moved the Quorum drive and the shared print server drive. So then I removed the virtual disks leaving just the RDM's. I had to mess around with the SCSI controllers a bit because the virtual disks were using 1:0 , 1:1 and the RDM's were using 2:0, 2:1. So the order definately changed as I noticed the networks for the virtual machines seemed to have swapped as well.

Anyway it seems I can not power on the VM's on seperate hosts. When I set a rule to seperate the hosts ESX says it can not find any suitable hosts to power the VM on... I have checked everything. Both SCSI controllers on both vm's are set to physical mode. I also tried removing both the rdm's from both vm's so I fixed the scsi numbers so now the VM disk is using 0:0 and the RDM's are using 1:0 and 1:1.

Is there anything else I can check? Any logs which will tell me why it wont turn on? If I have them both turned on (on the same host) and try to vmotion one of them (which I know is not supported) it comes back saying " Unable to migrate from esxhost1 to esxhost2 : Virtual Machine is configured to use a device that prevents migration: Device 'SCSI Controller 1' is a SCSI controller engaged in bus-sharing."

Would it say the above error even if the controller is in physical mode? I am thinking maybe because I had to mess around with the controllers it thinks the controller is in virtual mode still...

Any help would be great thanks!!

[sflanders]

Have you checked out the following guide: http://www.vmware.com/pdf/vi3_35/esx_3/r35u2/vi3_35_25_u2_mscs.pdf. Some differences between MSCS on one host and MSCS on two hosts exist. Are you saying you are enable to move one of the VMs to another host?

[packetboy]

Hi thank you for your answer... Yes I have been following the above guide. I am saying the two VM's will start fine on one esx host but they can not start on two seperate esx hosts. Even tho they are using RDM's and the SCSI bus is set to physcial for both VM's.

[rubensluque]

Hi,

Can you see the RDM disks from another ESX host ? When you have two mscs nodes in separated hosts only one node is pointed directly to RDM disk, The other node should be pointed to rdm files only.

[beyondvm]

have you verified that your SCSI bus is set to share (physical or virtual mode depending)? Page 23 of the doc linked earlierexplains in detail. I have successfully created clusters using virtual disks on 2 hosts in the past even if it may be unsupported. This setting is important for RDM and for regualr disks.

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[packetboy]

Sorry guys it was me being an idiot... One of the vm's was powered off and I assumed if there was a DRS rule in place to keep 2 vm's seperate the cluster would know to try to start it on another host but this isnt the case.. I just migrated the vm to a different host and powered it on fine..

doh feel pretty stupid right now....