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I'm trying to map an existing 4tb LUN from a Fibre Channel SAN, through to a VM in my ESX4 environment. It keeps telling me that the VMDK file size exceeds the the maximum size supported by the datastore.

I've tried in Physical compatibility mode, and also both Virtual styles.

I'm a little confused by this as we had the same LUN mapped through to another VM when we were running ESX3.5... I've also noticed that some of my other RAW mappings are generating extremely large VMDK files on the ESX servers. Does anyone know if this change in behaviour is intentional? And if so why? It doesn't seem to me that if the LUN is mapped directly to the VM that it's size should be relevant.

We're running 4.0.0 build 236512, and 4.0.0 build 219382 and I've not had any success on either.

Any insight or advice would be much appreciated!


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up vote 1 down vote accepted

VMWare has a 2tb Limitation on Raw devices :

Hope this helps ;-)

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This helped immensely. Put me onto this one for VI4. Thanks! – Tom Gardiner Mar 19 '10 at 4:29

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