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Martin_C1
Contributor
Contributor

Virtual disk 'Hard Disk 2' is a mapped direct-access LUN that is not accessible.

Hi everyone,

We have only just started setting up a VMWare enviroment, we have about 10-15 virtual machines setup, all running windows 2003 server and currently accross 2x 3.5 ESX servers, using Virual Center.

If we try to migrate a particular virtual machine we get the below error message, the SAN LUN is setup with access to both ESX servers like all the other virtual machines that work fine.

The LUN is an RDM; we have tried it in both modes, and have the same results.

Virtual disk 'Hard Disk 2' is a mapped direct-access LUN that is not accessible.

Any help or advice would be appreciated, please let me know if I have posted this in the wrong section of the forum.

Thanks

Martin C

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Martin_C1
Contributor
Contributor

We have figured it out, it seems when you make LUN's available to the ESX servers and click "Rescan", if you add multiple LUN's it assigns them in a random order and different ESX servers sees the different LUN's with different ID's.

Once we re-added the LUN's one at time in the correct order, so both ESX servers had the same LUN ID's for the same LUN's it started working.

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fmorenol
Contributor
Contributor

Hi,

I have the same problem, so re-added the LUN¡s so both ESX servers have the same LUN ID but still giving the same error message about virtual disk "hard disk " is a mapped direct access LUN that is not accessible.

Has anyone experienced an resolved this trouble? All that I have found is that mscs is not compatible but vmware configuration guide explains how to install it?

Thanks in advanced.

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patrickds
Expert
Expert

Can't you set HostIDs on your LUNs on the SAN?

That way, the LUNs will always get the same ID on your ESXes, no matter in what order they're discovered.

Now, if you reboot an ESX, you risk having your LUNIDs changed en mismatching between the ESXes again.

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