Cisco Systems Cisco IOS XR manual Integrated Switch Functions, Rack Type Description

Chapter 3 Bringing Up the Cisco IOS XR Software on a Multishelf System

Integrated Switch System

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.

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:

	Cisco IOS XR Getting Started Guide
3-22	OL-10957-02