If you are attaching a U320 SCSI tape drive (Particularly LTO3 Drives) to a VMWare ESXi 4.1 Host you may experience the problem where the tape drive does not show up when you try to attach a SCSI device to the Virtual Machine Guest Server (even though it is detected during the server boot process).

To resolve this issue, follow this process.

Using the VI Client, attach to the ESXi Host server

Close down all running Virtual Machines.

Then go to the physical console and enable Remote Support on the ESXi Console

Next,  go to the command line interface and type in the following command

esxcli nmp satp deleterule –satp VMW_SATP_ALUA –claim-option tpgs_on

then press <enter>

Go back to your VI Client, and put the host server into maintenance mode.

Using the VI Client, reboot the host server.

When the server is up again, reconnect your VI Client to it and take the server out of maintenance mode.

Edit the server you wish to attach the tape drive to.

Select ADD and choose SCSI Device.

Your tape drive should now be listed as an available device.