Raw Device Mapping

[RainerP]

Hi there,

I would like to achieve the following:

Create one VM (Windows 2003 Server) with one VMDK for the OS (15 GB) and one RDM (200 GB) for Datafiles on a SAN (EMC 500).

In case of a failure within the VM I may be required to attach a physical Server to the SAN and access the data on the RDM.

I know that I have to do the zoning etc. on the SAN to allow the physical Server access to the LUN but is there anything else I have to consider ?

Regards,

Rainer

[bister]

Sounds funny for me: You are protecting a VM by a standby physical server Normally people do it other way round ...

But to your question: You need to ensure that the backup server has no access to the LUN as long as the VM is running.

[stuart_ling]

Depending on the application that you are supporting you could consider a physical to virtual cluster.

[RainerP]

No, maybe a misunderstanding. I don't want to protect my VM. I only need the physical Machine in case I have a problem with the application software within the VM. Just to proof then that the problem is not within the virtualization layer

The physical Server will access the LUN only when the VM is down.

Regards,

Rainer

Message was edited by:

RainerP

[bister]

Ah nice idea.

That should be enough: RDM to VM, in case of necessary switch just shutdown VM and enable the physical server with correct SAN zoning to the RDM LUN.

[RainerP]

My SAN Admin told me that it is not possible to connect the LUN to a physical machine once it was connected to a VM. Can anybody confirm that ?

I know that I can't use the LUN at the same time with 2 machines, but it should be possible to use it after the VM is powered off right ?

Regards

Rainer

[bister]

You can connect a LUN to whatever server you want. Connecting a VMFS-formatted LUN to a Windows server is also possible: Done so with VMware Consolidated Backup Proxy. And if the LUN isn't VMFS-formatted an OS which is identical in VM and on physical can use that LUN.

[RainerP]

And this is exactly what I want to do.

Have the LUN attached to either a virtual or physical Windows 2003 Server.

Any idea where I could find something official on that subject ?

Thanx for your answer,

Rainer

[bister]

Look here http://pubs.vmware.com/vi301/wwhelp/wwhimpl/js/html/wwhelp.htm

(in detail for RDM: http://pubs.vmware.com/vi301/san_cfg/esx_san_cfg_esx_and_san.4.13.html)