Looking for the options to achieve the following:
I have a physical windows file server direct attached to a VNX5500 via fiber. A 4TB LUN is presented to it. There is a need to move this server to a vm which will be running on the ESXi host attached to this same VNX5500 via iSCSI. My first thought would be to P2V the physical server, however some of my colleagues, less familiar with storage, are suggesting simply to remap this 4TB LUN to a vm, which makes no sense.
Are there any other options to achieve that?
Any input is appreciated.
Hi, they might be thinking of presenting the LUN and then creating an RDM.
At that size, only supported on vmfs5 and esxi 5.5.
I agree, technically, it is possible. However, in reality should you just un-present the LUN (which has 4TB worth of user data on it - all of it is file shares) from an existing windows server, and map it as an RDM to the VM. I thought you cannot just rip disk out of a server and install it into a new one and have all the data intact. I think there are going to be a lot of issues with the drive being recognized by the new host.
You'd be surprised how resilient they can be, and like dynamox I've done many and most have been totally trouble free.
If you have the resources and would feel more comfortable, you could build/p2v a vm in parallel, synch changes and then swing access across.
It should work fine, especially if it's a standalone server.
- Disconnect LUN from the physical server.
- P2V the server
- Reconnect LUN to VM
I've done many of these types of P2Vs over time, even with an additional step to storage VMotion the machine afterwards and turn the RDM into a VMDK. Unfortunately your LUN is 4TB so that's going to have to stay an RDM...
Alternatively the approach your colleagues propose would also work (the data would be accessible) but things like shares would have to be recreated (since you're connecting it to a new VM with possibly a different network name).
"I thought you cannot just rip disk out of a server and install it into a new one and have all the data intact. I think there are going to be a lot of issues with the drive being recognized by the new host."
In general there is no problem with this for non-system volumes (meaning not the OS drive itself) assuming OS compatibility, and actually this is a use case for RDMs from VMware. If you have the need or desire to move between physical and virtual servers (like reproducing a problem with a VM on physical), preserving the data, RDMs fit this mold because RDMs are not formatted when they are pulled into the system. There is just a mapping or pointer file that references the LUN.
In your case I would recommend setting up a simple test server and run through the process entirely. Physical windows server, present 50GB LUN from VNX, create a folder and some files, and a few shares. By going through the process in this manner you will:
Emphasis on #2...you wouldn't want to go through this process only to lose all of the shares...depending on exactly how many you have, anyway.
Also don't forget that you can leverage snapshots as well for some peace of mind, assuming you have the proper licensing. This gives you a point in time copy that you can take instantly and revert to quickly if things go sideways.
Thank you all for the input, very much appreciated, it is very valuable. By any chance is there an EMC document that outlines anything of this nature: remapping a LUN from a physical windows to server to a VM as an RDM?