Switch GUIDs Overview

Global unit identifiers (GUIDs) are unique 64-bit strings that identify nodes such as switches and channel adapters. For the Sun Datacenter InfiniBand switches, GUIDs are modified to identify the node’s role and location. The following table describes the GUID’s structure.

The five fields of the GUID are described as follows:

• MAC – Bits 63 through 16 are the Machine Allocation Code (MAC) address. A standard for network components, the MAC address is typically provided by manufacturers in a 6-byte, colon delimited string. For example, 00:11:22:33:44:55.

• Type – Bits 15 through 12 is the type of board on which the node resides.

• Pos – Bits 11 through 8 identify the position of the board within the switch.

• Device – Bits 7 through 4 identify which device on the board has that node.

• Num – Bits 3 through 0 are numbers reserved for the programs which modify the GUID. In most occurrences, the value is 0x2.

The following table provides values for Type, Pos, Device.

For example, given the following output from the ibswitches command:

Switch  : 0x0021283a8620b0e0 ports 36 "Sun DCS 72 QDR switch 1.1(FC)" base port 1 lid 24 lmc 0

The GUID is 0x0021283a8620b0e0 or 0021283a8620 B 0 E 0. Using the information provided in this topic:

• The MAC address is 0x0021283a8620 or 00:21:28:3A:86:20.

• The type is 0xB, or a 72-port board.

• The position is 0x0.

• The device is 0xE, or I4 switch chip E.

• The number is 0.

Related Information

• Switch Reference, ibnetdiscover command

• Switch Reference, ibnodes command

• Switch Reference, ibswitches command

• Switch Reference, ibhosts command

• Identify All Switches in the Fabric

• Switch Hardware Problems

• InfiniBand Fabric Problems

• Understanding the LEDs

• Understanding Routing Through the Switch