B Determining Linux SCSI Parameters

For the Linux and UNIX platforms, if you do not know the SCSI parameters of a tape device, then you must determine them before you begin installation. This appendix describes procedures for determining SCSI device parameters on Linux and UNIX.

Determining SCSI Device Parameters on Linux

To obtain tape device information on Linux, use the cat command to view the contents of /proc/scsi/scsi. For example:

# cat /proc/scsi/scsi

See Also:

"Configuring Devices on Linux Media Servers" for information about configuring attach points for Linux

Example B-1 shows sample output for a host called storabck05 with two attached tape devices.

A device of type Sequential-Access, such as the first tape device in the list, is a tape drive. A device of type Medium Changer, such as the second tape device, is a tape library.

For each tape device, the information needed is found in the line that reads:

Host: scsi0 Channel: 00 Id: 02 Lun: 00

The output can be interpreted as follows:

  • The host bus adapter number is the numeric part of the value scsin. For example, for both tape devices in this output the host bus adapter number is 0.

  • The value for Channel is the SCSI bus address. For example, in this output the SCSI bus address is 0.

  • The value for Id is the target ID. For example, in this output the ID of the tape drive is 2, and the ID of the tape library is 4.

  • The value for Lun is the SCSI LUN. For example, in this output the SCSI LUN of both tape devices is 0.

By convention, the tape library and tape drive can each be assigned 0 as the Oracle Secure Backup logical unit number.

Based on the output shown in Example B-1, Table B-1 summarizes the tape device information for storabck05.

Table B-1 storabck05 Device Summary

Device Host Bus Adapter SCSI bus address Target ID SCSI LUN

Library

0

0

2

0

Tape drive

0

0

4

0

Example B-1 Sample /proc/scsi/scsi Contents

Attached devices:
Host: scsi0 Channel: 00 Id: 02 Lun: 00
  Vendor: IBM      Model: ULTRIUM-TD2      Rev: 4772
  Type:   Sequential-Access                ANSI SCSI revision: 03
Host: scsi0 Channel: 00 Id: 04 Lun: 00
  Vendor: ADIC     Model: Scalar 24        Rev: 237A
  Type:   Medium Changer                   ANSI SCSI revision: 02