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dewan
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1x RDM disk shared by 1 x Virtual server & 1 x Physical server

Hi All,

I would like to share an RDM disk by two nodes ( 1 x virtual server & 1 x physical server ). Both servers have SAN visibility.

I have tried following options:

http://oskb.wordpress.com/2011/12/29/vmware-share-rdm-between-2-vms/ :

On Node1:(file server in my case)
1.In the vSphere Client inventory, select the newly created virtual machine and select Edit Settings. The Virtual Machine Properties dialog box appears.
2.Click Add, select Hard Disk, and click Next.
3.Select Raw Device Mappings and click Next.
4.Select an unformatted LUN and click Next.
5.Select a datastore and click Next.[This datastore must be on a SAN because you need a single shared RDM file for each shared LUN on theSAN]
6.Select Physical as the compatibility mode and click Next.[A SCSI controller is created when the virtual hard disk is created.]
7.Select a new virtual device node (for example, select SCSI (1:0)), and click Next.[NOTE This must be a new SCSI controller. You cannot use SCSI 0]
8.Click Finish to complete creating the disk.[The wizard creates a new SCSI controller and a new hard disk]
9.In the Virtual Machine Properties dialog box, select the new SCSI controller and click Change Type.[Windows Server 2008 LSI Logic SAS]
10.On the Virtual Machine Properties dialog box, set SCSI Bus Sharing to Physical and click OK.

On Node2: (backup server)
1.In the vSphere Client inventory, select the newly created virtual machine and select Edit Settings. The Virtual Machine Properties dialog box appears.
2.Click Add, select Hard Disk, and click Next.
3.Select Use an existing virtual disk and click Next.
4.In Disk File Path, browse to the location of the quorum disk specified for the first node.
5.Select Physical as the compatibility mode and click Next.[A SCSI controller is created when the virtual hard disk is created]
6.Select the same virtual device node you chose for the first virtual machine’s shared storage disks (forexample, SCSI (1:0)), and click Next.
7.Click Finish.[The wizard creates a new hard disk and a new SCSI controller.]
8.In the Virtual Machine Properties dialog box, select the new SCSI controller and click Change Type.[Windows Server 2008 LSI Logic SAS]
9.Set SCSI Bus Sharing to Physical and click OK

I am able to see the shared disks (RDM) in both Nodes using the above mentioned steps. However, if I make any data change to Node 1 e.g. create folder - it won’t reflect on Node 2 unless I restart the server.

Reason for doing this is to present file server RDM disk to a backup server (physical) for faster transfer rate from disk to tapes - as the data will then appear to be on the local disk of the backup server.

It would be even better if the RDM on Node 2 (backup server in my case) can be presented in read only mode.

Any suggestions ?

Thank you!

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a_p_
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Anyway, you can present a virtual disk to multiple guests, but you have to ensure the guest's file system supports simultaneous access, which - in case of Windows - is currently only supported for Hyper-V. If you access a file system which does not support this, you will corrupt the file system this way!

André

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a_p_
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Anyway, you can present a virtual disk to multiple guests, but you have to ensure the guest's file system supports simultaneous access, which - in case of Windows - is currently only supported for Hyper-V. If you access a file system which does not support this, you will corrupt the file system this way!

André

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mcowger
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You've presented the LUN, but you haven't taken care of the filesystem.  You need a filesystem that can handle clustered environments like this, which you dont have.

--Matt VCDX #52 blog.cowger.us