System Administration Guide: Devices and File Systems

Automatically Configuring SCSI Disk Drives

The format utility automatically configures SCSI disk drives even if that specific type of drive is not listed in the /etc/format.dat file. This feature enables you to format, create slices for, and label any disk driver that is compliant with the SCSI-2 specification for disk device mode sense pages.

Here are other options for adding disks:

The following steps are involved in configuring a SCSI drive by using automatic configuration:

After the reconfiguration boot, invoke the format utility. The format utility will attempt to configure the disk and, if successful, alert the user that the disk was configured. For step-by-step instructions on automatically configuring a SCSI disk drive, see How to Automatically Configure a SCSI Drive.

Here's an example of a partition table for a 1.3-GB SCSI disk drive that was displayed by the format utility.

Part    Tag    Flag     Cylinders     Size        Blocks
   0     root    wm       0 -   96    64.41MB      (97/0/0)
   1     swap    wu      97 -  289   128.16MB     (193/0/0)
   2   backup    wu       0 - 1964     1.27GB    (1965/0/0)
   6      usr    wm     290 - 1964     1.09GB    (1675/0/0)

ProcedureHow to Automatically Configure a SCSI Drive

  1. Become superuser or equivalent role.

  2. Create the /reconfigure file that will be read when the system is booted.

    # touch /reconfigure
  3. Shut down the system.

    # shutdown -i0 -gn -y

    Brings the system down to init level 0, the power-down state.


    Notifies logged-in users that they have n seconds before the system begins to shut down.


    Specifies that the command should run without user intervention.

    The ok prompt is displayed after the system is shut down.

  4. Turn off the power to the system and all external peripheral devices.

  5. Ensure that the disk you are adding has a different target number than the other devices on the system.

    Typically, a small switch is located at the back of the disk for this purpose.

  6. Connect the disk to the system, and check the physical connections.

    Refer to the disk's hardware installation guide for details.

  7. Turn on the power to all external peripherals.

  8. Turn on the power to the system.

    The system boots and displays the login prompt.

  9. Log back in as superuser or assume an equivalent role.

  10. Invoke the format utility, and select the disk that you want to configure automatically.

    # format
    Searching for disks...done
    c1t0d0: configured with capacity of 1002.09MB
    0. c0t1d0 <SUN1.05 cyl 2036 alt 2 hd 14 sec 72>
    1. c0t3d0 <SUN1.05 cyl 2036 alt 2 hd 14 sec 72>
    Specify disk (enter its number): 1
  11. Type yes in response to the prompt to label the disk.

    Typing y causes the disk label to be generated and written to the disk by using SCSI automatic configuration.

    Disk not labeled. Label it now? y
  12. Verify the disk label.

    format> verify
  13. Exit the format utility.

    format> q