Persistent Naming Support on Windows Server 2008, 2012, 2016, and 2019

The Windows tape driver has an option for enabling device object names that persist across restarts of the operating system. For example, if your tape drive has the name \.\tape4801101 and the persistent naming option is used, then \\.\tape4801101 is reserved for use by that device after an operating system restart.

Complete the following steps to enable this feature.

  1. Add a DWORD value to the registry called PersistentNaming and assign it a value 1
    • On Windows Server 2008: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\ibmtp2k8
    • On Windows Server 2012: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\ibmtp2k12
    • On Windows Server 2016: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\ibmtp2k16
    • On Windows Server 2019: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\ibmtp2k19
    .
  2. Restart your system. Then, the system writes information to the registry to associate the Worldwide Node Name from Inquiry p. 0x83 with the persistent name used by the operating system.
    • If the Worldwide Node Name is unavailable, or the drive is a virtual (that is, emulated) drive, then the device serial number is used rather than the Worldwide Node Name.
    • If the PersistentNaming option is not specified in the registry, then your devices might not be able to claim the same device name after restart or driver initialization.
You can find registry subkeys with persistent naming information.
  • On Windows Server 2008: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\ibmtpbs2k8
  • On Windows Server 2012: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\ibmtpbs2k12
  • On Windows Server 2016: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\ibmtpbs2k16
  • On Windows Server 2019: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\ibmtpbs2k19

Alternately, you can use the Windows Device Manager to examine the device number to determine that persistent naming is enabled on your host. Persistent names contain tape device numbers that are based at 4801101 (which is the decimal equivalent of hexadecimal 0x49424D and ASCII "IBM®").

If two physical paths exist to a drive and different Windows device names are required (which happens, for example, when two different HBAs are connected to the drive and Data Path failover is disabled), the first discovered path claims the persistent device name. Any subsequent paths that connect to the same device receive names according to the order in which they are discovered by the Windows Device Manager.

Note: Persistent naming is not set by default. For disabling it, set the PersistentNaming value to 0 and restart the system.