Cisco Systems EA6500 Manual De Usuario

These sections describe supervisor engine redundancy configuration guidelines and restrictions:

The following guidelines and restrictions apply to RPR+:

RPR+ redundancy does not support configuration entered in VLAN database mode. Use global 
configuration mode with RPR+ redundancy (see 

).

Configuration changes made through SNMP are not synchronized to the redundant supervisor 
engine. Enter a copy running-config startup-config command to synchronize the configuration on 
the redundant supervisor engine.

Supervisor engine redundancy does not provide supervisor engine mirroring or supervisor engine 
load balancing. Only one supervisor engine is active. Network services are disrupted until the 
redundant supervisor engine takes over and the switch recovers.

With RPR+, both supervisor engines must run the same version of Cisco IOS software. If the 
supervisor engines are not running the same version of Cisco IOS software, the redundant supervisor 
engine comes online in RPR mode.

The Forwarding Information Base (FIB) tables are cleared on a switchover. As a result, routed traffic 
is interrupted until route tables reconverge.

Static IP routes are maintained across a switchover because they are configured from entries in the 
configuration file. 

Information about dynamic states maintained on the active supervisor engine is not synchronized to 
the redundant supervisor engine and is lost on switchover.

These are examples of dynamic state information that is lost at switchover:

Frame Relay switched virtual circuits (SVCs)

Frame Relay-switched DLCI information is maintained across a switchover because Frame 
Relay-switched DLCI configuration is in the configuration file. 

All terminated PPP sessions 

All ATM SVC information

All terminated TCP and other connection-oriented Layer 3 and Layer 4 sessions

BGP sessions 

All Automatic Protection System (APS) state information