What is the NetWorker Common Device Interface (CDI)

The Common Device Interface (CDI) media analysis tool was introduced with the NetWorker software to provide a generic passthrough solution for all operating systems to control tape and status collection.
  • CDI controls tape and status collection, and does not:
    • Depend on the operating system driver mechanisms
    • Interfere with device read/write operation
  • The following are advantages to using CDI:
    • CDI enables the use of TapeAlert feature. If there are errors, the tape drive can send a full message to the NetWorker software rather than a generic error code. TapeAlert provides intelligent tape drive management, and is an extension of the SCSI error system.
    • CDI allows on-demand auto-cleaning of tape devices.
      Magnetic tape I/O can cause streaming mode to fail on tape drives, \writes file markers, and decreases the overall performance of the drive.
    • CDI is required for many new features added to recent versions of the NetWorker software. The new features include device serial number scanning for early detection of device ordering issues (added in NetWorker version 7.4 Service Pack 3.)
    • CDI is required for WORM, and future encryption support.
    • CDI is required for persistent SCSI reserve/release support.
    • CDI will be required for any future device management enhancements.
    • NetWorker provides additional command line tools for diagnostics and tape device control, available only when CDI is enabled. The man pages or the Command Line Reference Guide provides details on cdi_* commands.
    • If CDI is enabled, NetWorker release 7.4 Service Pack 4 or later must be used for remote storage node support.