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Cisco IOS XR Getting Started Guide
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Chapter3 Bringing Up the Cisco IOS XR Sof tware on a Multishelf System
Integrated Switch System
Test the FE links to all the rack hardware periodically.
Keep the local state information synchronized to the rack master.
Rearbitrate the shelf ownership if the primary router releases ownership.

Integrated Switch Control Network Topology

Once the 22-port SCGE cards are installed, the control network topology ceases to be a simple
hub-and-spoke set of connections.
A control network topology provides the following functions:
Each RP in a line card chassis is connected to two different 22-port SCGE cards in a fabric chassis.
The 22-port SCGE cards are interconnected in a full mesh to provide an available control network
with multiple redundant Ethernet connections.
The 22-port SCGE cards appear to be a backbone in which d ifferent RPs are connected from the
outside.
Both the 22-port SCGE cards and RPs run the rapid spanning tree protocol (RSTP) to provide a
loop-free topology.

LED Definitions for the Integrated Switch System

The 22-port SCGE displays the LEDs on the front panel foe every port. Tab le 3-5 lists the LEDs that are
used to obtain information about the link.
Implementing the Integrated Switch System
This section presents topics on how to implement the integrated switch system:
Implementing the Integrated Switch Through ROMMON, page 3-23
Implementing the Integrated Switch in Cisco IOS XR, page 3-24
Booting Up the Integrated Switch Network, page 3-24
Reenabling the Ports, page 3-24

Implementing the Integrated Switch Through ROMMON

When the 22-port SCGE comes out of reset, ROMMON must initialize the switches so that no loops get
formed and the processor can communicate with the rest of the system. ROMMON configures the
switches.
Table3-5 LEDs for the Integrated Switch
LED Description
Green Link Up
Blinking Green Activity
Amber Port error disabled Unidirectional Link Detection
(UDLD)
Off Link Down