try with this Microsoft KB, is HP P212 driver issue:
Números de artículo de KB: 943545
Try this solution from Symantec:
"How To configure a tape device with a virtual machine in ESX 4.0 and ESX 4.1" (http://www.symantec.com/docs/TECH146293)
"How to properly configure a VMWare ESX virtual machine to use tape devices which are connected to the host server via SCSI Passthrough" (http://www.symantec.com/docs/TECH70246)
I removed the P212 card and installed a HP SC44Ge HBA (P/N 416096-B21).
Now I've this configuration:
HP DL380 G7
VMWare 5.0.0 (build 469512)
HP SC44Ge (passthourgh on a Win 2008 R2 vServer)
HP SAS external cable (P/N AE466A)
connected on HP Storageworks 1/8 G2 Tape Autoloader (P/N AH558A)
driven by Symantec Backup Exec 2012
HP and wmvare both told me that this solution is not certified (they want me to install backup on a physical machine), but it works!
time lost: 3 weeks...
This is only for People who searches about esxi 5.x hp p212 Controller passtrough and symantec backup exec.
we had an Installation with esxi 5.1 and a p212 Controller not in passtrough and symantec backup exec 2014 SP1. it was working without any Problems until we upgraded the esx to Version 5.5U2
After the upgrade i was not able to ad the device over add scsi device, i Need to add the p212 Controller in passtrough to see the Controller under device Manager in Windows sbs2011.
after a reboot of the host we had a purple Screen, so i downloaded the latest spp from hp to install latest Firmware for all devices DL380G7 and i also installed the latest patches from vmware in update mode
because of hp oem esxi Image Installation.
After a host reboot i saw the tape drive in device Manager so i installed the tape Driver from symantec but this was a bad idea, the Server told me to reboot because of a Hardware Change, after the reboot the tape drive
was no longer visible in device Manager.
i uninstalled the tape Driver shutdown the guest, removed p212 from passtrough, reboot host, added again p212 in passtrough, reboot host and don't installed symantec Driver and voila since them it is working without
any Problems and we have a working backup in unsupported mode .
So believe me, never never use the tape Driver from symantec in esxi
we've differend unsupported installations of vmware esxi, hp tape drives and symantec backup exec. if you've any Problems, ask me I can help for sure.
Greetings and good luck
I have the same problem with my LTO 4 Tape. CAn you help me