Cisco Systems UBR7225VXR specifications MAC-Layer Address

Chapter 1 Cisco uBR7225VXR Overview

Cisco uBR7225VXR Network Interface Overview

Figure 1-3 Cisco uBR7255VXR Chassis and Cable Interface Line Cards

uBR7225-VXR

0	1		S2	US3	4	U	S5
	US	U			US
US

				4	5	6
0	1	2	3	US	US	US
US	US	US	US

	uBR - E18U	S
		D
		0
		-
		R
		F
7	uBR - E28U	D
		S0
US		RF
		-

ENABLED

D

S1

-

R

F ENABLED

1

2

270493

1

Cable interface line card slot 1

2

Cable interface line card slot 2

MAC-Layer Address

All LAN interfaces (ports) require unique MAC-layer addresses, also known as hardware addresses. Typically, the MAC address of an interface is stored on a memory component that resides directly on the interface circuitry; however, the OIR feature requires a different method. For a description of OIR, refer to the “Online Insertion and Removal” section on page 5-1.

The OIR feature allows you to remove a cable interface line card and replace it with another identically configured one. If the new cable interface line card matches the cable interface line card you removed, the system immediately brings it online. In order to allow OIR, an address allocator with a unique MAC address is stored in EPROM on the Cisco uBR7225VXR universal broadband router midplane. Each address is reserved for a specific slot in the router regardless of whether a cable interface line card resides in that slot.

The MAC addresses are assigned to the slots in sequence. This address scheme allows you to remove cable interface cards and insert them into other universal broadband routers without causing the MAC addresses to move around the network or be assigned to multiple devices.

Note Storing the MAC addresses for every slot in one central location means that the addresses stay with the memory device on which they are stored.

For information on the commands used to configure your Cisco uBR7225VXR router, refer to the Cisco IOS Configuration Fundamentals Configuration Guide at the following URL:

http://www.cisco.com/en/US/docs/ios/fundamentals/configuration/guide/12_4/cf_12_4_book.html

Also refer to the Cisco IOS Configuration Fundamentals Command Reference at the following URL:

http://www.cisco.com/en/US/docs/ios/fundamentals/command/reference/cf_book.html

Cisco uBR7225VXR Universal Broadband Router Hardware Installation Guide

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