Customer requires the file server as a VM but the main sharing drive should be mapped directly to SAN LUN other than VMDK file.
For this i am thinking two options
1) Mapping a RDM to the file-server as drive
2) Enable iSCSi intiator in Windows Server and map the SAN target directly. In this scenario, ESXi will have any knowledge on this mapping.
Suggest me which one is the best option
In first case, the RDM would do good for the VM to have access to the FC Lun. However, there will still be involvement of kernel. While in second case, the vmkernel will play the role of gateway/authentication, blah, blah.
I would recommend to take a look at NPIV to the VM.
Go with option 1. Map the LUN to the VMware host, and attach to the VM. The MS iSCSI initiator is horrid, plus LUN manageability is much simpler in the vSphere client vs the MS iSCSI initiator. Also consider the RDM compatibility mode when attaching the RDM to the VM. I would suggest the virtual compatibility mode, it give you the access of a raw device but the advantages of a VMFS drive. See notes below from VMware KB 2009226
Customer has the following setup
iSCSi SAN with 12 TB having two LUN's
LUN 1: For ESXi Datastore
LUN 2: Direct Access to Windows Files Server using as H Drive (Not RDM)
Two ESXi Servers
1) ESXi 1 --> 10 VM's
2) ESXi 2 --> 2 VM's
Now we found issues with HP Storage as it has OLD outdated firmware which has many bugs.
So we have decieded to upgrade the firmware and also repartitoning of LUN's
We have bought FC SAN on renatal basis with two FC HBA's connected to two ESXi Servers Each for moving all the VM's and also file server data (which is stored on LUN direclty).
Once storage firmware is upgraded then again we have to move all the VM"s and file server data back to iSCSi SAN.
I am thinking that there will be any challenges for VM migrations, but how to transfer the file server data without any downtime. Is vmdk is suggested for file Server migrations. Customer is very particular about keeping the file Server on direct LUN.
Can i have your suggestion on this?
@tomtom901: Previous engineers are suggested to customer. So customer is unable to take decision now. Can you help me in getting any web link saying that VMDK's are good for file servers.
Here is one link from the vmware blogs team. Note at the bottom the recommendation to use VMDK as a default. In my organization all of our business critical applications web, sql, mail are all using .VMDK drives.