ESXi question regarding RDM

[farscapesg1]

Hopefully this is a quick answer

I'm working through migrating from a physical WHS box to a VM on a new server (home environment). Currently, I have an eSATA dock that I plug a hard drive into once a month to backup my important data to a 1.5 TB SATA disk. In my new configuration, I'm passing the drives for to the VM with RDM (yeah, I know local SATA RDM disks aren't officially supported). Will the ESXi recognize when I connect/disconnect the drive, or will ESXi generate a new identification for the device every time?

On a related note, I've thought about passing the SAS controller (integrated 1068e on the motherboard) to the VM via PCI Passthrough. I'm assuming if I do that then everything will recognize as normal (connecting/disconnecting) and I might even get SMART readings for the drives? If that is the case, what is the official limit for PCI Passthrough devices? I've seen 2 and 4 around the Internet. I need to passthrough 2 TV tuner cards for certain, so if the limit is 2 that limits my options.

 

[defuseme2k]

VMDirectPath I/O is limited to 2 devices per guest prior to 4.1, but increased to 4 in 4.1. So it depends on what version of ESXi you have installed. Hopefully the ' SATA controller' isn't also booting your ESXi server or you'd have major issues afterward! This is probably your best option since it seems you don't care about being "supported" anyway.

Unplugging a SATA disk from the ESXi server while it is running sounds like a very bad idea, especially presented as an RDM to your guest. Using VMDirectPath I/O should give you hte functionality as if it were running on a physical windows server, and the hot add/remove should work.

 

[farscapesg1]

Yeah, I really don't like the idea of disconnecting a disk assigned to a RDM vmdk file. The other option is just to connect via USB instead of eSATA. The increase to 4 devices (I'm running 4.1) makes me feel better

The motherboard I'm using a Supermicro X8ST3-F, so it has 6 onboard SATA ports (used for the ESXi datastores with the ESXi OS running off a 4GB USB drive). The board also has a seperate LSI 1068e chipset providing 8 SAS/SATA ports.

I went ahead and set it up to pass the SAS controller and have it working now. Apparently all the controls don't get passed through though since the WHS console doesn't show any drive temp or disk access, but that isn't a major concern for me TBH.

I'll play around with this for awhile in PCI-passthrough mode with a couple other drives in RDM (outside the WHS drive pool for TV recording) and see how things go...