Just found this very interesting article http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1013109 describing a problem with Windows 2008 and ESX 4 virtual hardware version 7.
In short the article states that you might have the disks go offline in a Windows 2008 VM if you
- Upgrade virtual hardware from version 4 to 7
- Installing a new VM with virtual hardware 7
There is two ways to get around this (taken from the VMware KB 103109)
- VDS_SP_UNKNOWN = 0x0
- VDS_SP_ONLINE = 0x1
- VDS_SP_OFFLINE_SHARED = 0x2
- VDS_SP_OFFLINE = 0x3
SAN Policy : Offline Shared DISKPART> exit
- Log in to your system as an Administrator.
- Click Computer Management > Storage > Disk Management.
- Right-click the disk and choose Online.