Cisco Router Cisco IOS XR User Manual

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Cisco IOS XR Getting Started Guide
OL-10957-02
Chapter 3 Bringing Up the Cisco IOS XR Software on a Multishelf System
Integrated Switch System
Integrated Switch Functions
The 22-port SCGE performs the following functions:
• Arbitrate for shelf ownership (active mode or standby mode) with the other 22-port SCGE card that
is installed on the rack.
• Provide 22 GE ports for external system management communication across racks.
• Performs the same type of control plane functions as the current SCGE for the multichassis system.
• Performs the same type of control plane management functions as the Catalyst 6509. For example,
22-port SCGE card provides physical GE ports that allow control plane traffic to be distributed
throughout the fabric and line card chassis.
• Supports 22 GE ports and has the capability to support up to 72 line card chassis.
• Allows you to perform a hitless migration from an external Catalyst 6509 switch based network to
an internal 22-port SCGE based network with no loss of user or control traffic. For more
information, see Cisco CRS-1 Carrier Routing System Multishelf System Upgrade and Conversion
Guide.
• Validates the link state before running the Spanning Tree Protocol (STP) that prevents a link from
being unidirectional and causes a spanning tree loop.
• Checks the link for any unidirectional mode when a cable is plugged into the 22-port SCGE. If the
22-port SCGE software detects this condition, the port cannot be allowed to participate in the
spanning tree algorithm.
In active mode, you can perform the following functions:
• Download the Ethernet MAC addresses from the backplane EPROM and assign them to all boards
in the rack.
• Start up and monitor power supplies, rack fans, and thermal sensors within the fabric rack upon
request from the system management network.
• Start up board power supplies, download software images to the fabric cards in the rack upon request
from the system management network. Start and reset board processors.
• Send alarms, reset, and shut down portions of the rack hardware in case of abnormal or dangerous
conditions in the rack.
• Keep a log of the 22-port SCGE cards and rack activity on nonvolatile memory. Take core dumps
onto the hard disk.
• Initiate a self-reset and rearbitration for shelf ownership in case of a watchdog timeout.
• Control and monitor the fan speed.
In standby mode, you can perform the following functions:
Table 3-4 Differences Between Intra-Rack and Inter-Rack
Rack Type Description
Intra-Rack Switch Provides connectivity inside the rack through FE ports. These
switches are similar to the RPs.
Note The GE1 link on intra-rack switches on the 22-port SCGE card
is not connected.
Inter-Rack Switch Provides connectivity between the racks.

Cisco Router Cisco IOS XR Specifications

General

Brand	Cisco
Model	Router Cisco IOS XR
Category	Software
Language	English