JSI Tip 1599. How do I enable support for more than 8 Logical Unit Numbers (LUN)?

Starting with SP5, up to 255 LUNs are supported, but they are not enabled.

To enable large LUN support, use Regedt32 to navigate to:


where <Driver_Service_Key> is your SCSI driver name and <\[Number\]> is the SCSI adapter number (0 - 1st, 1 - 2nd, etc..).

On the Edit menu, Add Value name LargeLuns, a type REG_DWORD, and set the data value to 1.

NOTE - If the LargeLuns is added to the Parameters subkey and NO <\[Number\]> subkeys exist, it applies to all <Driver_Service_Key> adapters.

NOTE - Deleting LargeLuns, or setting it to 0, disables large LUNs.

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