Redundancy Configuration Guidelines And Restrictions; Hardware Configuration Guidelines And Restrictions - Cisco 7604 Configuration Manual

Supervisor Engine Configuration Synchronization

Redundancy Configuration Guidelines and Restrictions

These guidelines and restrictions apply to all redundancy modes:
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Hardware Configuration Guidelines and Restrictions

For redundant operation, the following guidelines and restrictions must be met:
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Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
7-10
With Release 12.2(18)SXD and earlier releases, when a redundant supervisor engine is in standby
mode, the two Gigabit Ethernet interfaces on the redundant supervisor engine are always active.
With a Supervisor Engine 720 and Release 12.2(18)SXE and later releases, if all the installed
switching modules have DFCs, enter the fabric switching-mode allow dcef-only command to
disable the Ethernet ports on both supervisor engines, which ensures that all modules are operating
in dCEF mode and simplifies switchover to the redundant supervisor engine.
With a Supervisor Engine 2 and Release 12.2(18)SXD1 and later releases, if all the installed
switching modules have DFCs, enter the fabric switching-mode allow dcef-only command to
disable the Ethernet ports on the redundant supervisor engine, which ensures that all modules are
operating in dCEF mode.
Supervisor engine redundancy does not provide supervisor engine mirroring or supervisor engine
load balancing. Only one supervisor engine is active.
Configuration changes made through SNMP are not synchronized to the redundant supervisor
engine. After you configure the router through SNMP, copy the running-config file to the
startup-config file on the active supervisor engine to trigger synchronization of the startup-config
file on the redundant supervisor engine.
Supervisor engine switchover takes place after the failed supervisor engine completes a core dump.
A core dump can take up to 15 minutes. To get faster switchover time, disable core dump on the
supervisor engines.
With a Supervisor Engine 720 and Release 12.2(18)SXF and later releases, if a fabric
synchronization error occurs, the default behavior is to switchover to the redundant supervisor
engine. In some cases, a switchover to the redundant supervisor engine is more disruptive than
powering down the module that caused the fabric synchronization error. Enter the no fabric
error-recovery fabric-switchover command to disable the switchover and power down the module
with the fabric synchronization error.
Cisco IOS running on the supervisor engine and the MSFC supports redundant configurations where
the supervisor engines and MSFC routers are identical. If they are not identical, one will boot first
and become active and hold the other supervisor engine and MSFC in a reset condition.
Each supervisor engine must have the resources to run the router on its own, which means all
supervisor engine resources are duplicated, including all flash devices.
Make separate console connections to each supervisor engine. Do not connect a Y cable to the
console ports.
Both supervisor engines must have the same system image (see the
Supervisor Engine" section on page
Chapter 7 Configuring NSF with SSO Supervisor Engine Redundancy
7-20).
"Copying Files to the Redundant
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