Tape Drives and SAS connectors

[J0B]

Hey guys, please forgive my ignorance but I'm hoping I can get some advice as I've been told conflicting things.

Bascially we have a PowerEdge 2950 which runs ESXi 4 no problems.

So we want to start backing up our VMs onto tape drives. If we bought a SAS card which is on the HCL list and attached a tape drive to it, would all the VMs be able to see it?

I guess what Im asking is is there some sort of SAS pass through to the VMs?

Thanks for any help and sorry if this is in the wrong section.

[lnairn]

Hi, you can passthrough the SAS port to one VM only, if you need that port to another VM you need de power off the VM, remove the SAS port, and add to another port.

First Check if you server support DirectPath I/O

[J0B]

Oh right, thats a bit of a PITA.

Having to take the server offline is a bit of effort just to change the SAS connection.

May I ask what you'd suggest/what is good practise?

Also, how would I check if the server supports DirectPass?

[geddam]

Initially I would recommend going through this KB article....http://kb.vmware.com/kb/1000024

VMDirectPath does have a number of requirements:

- The host chipset must support the option. Intel chipsets that support Intel Directed I/O include Intel Xeon 5500 systems, Intel Xeon 5400 systems and motherboards that are vPro certified. On the AMD side, the server should support AMD I/O Virtualization Technology (AMD IOMMU).

- Intel Directed I/O or AMD IOMMU should be enabled in the BIOS of the host

- A PCI device can only be allocated to a single VM at a time.

But again above all this...this option of using Tape drive for single VM and performing downtime..will not solve the purpose of what you are looking for.

Thanks,

Ramesh. Geddam

VCP 3&4, MCTS(Hyper-V)

[J0B]

Cheers the one server at a time thing doest really work for me though.

I'm thinking along the lines of have a seperate VM which would be the backup agent, so it was have the SAS connected to it and then a network share or something like that which all the other VMs backup too...am I in the right ball park?

[geddam]

Not the right ball park..A dedicated physical box for backups has always been proven best for backup operations (looking into factors like performance, visibility, monitoring, integration etc)....doesn't matter whether you are performing a virtual machine backup or a physical file level backup...

Thanks,,

Ramesh. Geddam,

VCP 3&4, MCTS(Hyper-V).

Please award points, if helpful

[J0B]

Cheers for your help. I know it's not best practise but having a VM as the backup agent is technically possible just not advisable?

[geddam]

YES

Thanks,,

Ramesh. Geddam,

VCP 3&4, MCTS(Hyper-V).

Please award points, if helpful