CHAPTER
6-1
Software Configuration Guide—Release 12.2(25)SG
OL-7659-03
6
Configuring Supervisor Engine Redundancy Using RPR and SSO
Catalyst 4500 series switches allow a redundant supervisor engine to t ake over if the active supervisor
engine fails. In software, supervisor engine redundancy is enabled by ru nning the redundant supervisor
engine in route processor redundancy (RPR) or stateful switchover (SSO) operating mode.
Note The minimum ROMMON requirement for running SSO is Release 12 .1(20r)EW1 or
Release 12.2(20r)EW1.
This chapter describes how to configure supervisor engine redundancy on the Ca talyst 4507R and
Catalyst 4510R switches. It also describes the relationship between SSO and Cisco IOS NSF-awareness.
This chapter contains these major sections:
Understanding Cisco IOS NSF-Awareness Support, page 6-2
Understanding Supervisor Engine Redundancy, page 6-3
Understanding Supervisor Engine Redundancy Synchronization, page 6-6
Supervisor Engine Redundancy Guidelines and Restrictions, page 6-7
Configuring Supervisor Engine Redundancy, page 6-8
Performing a Manual Switchover, page 6-11
Performing a Software Upgrade, page 6-12
Manipulating Bootflash on the Redundant Supervisor Engine, page 6-14
Note For complete syntax and usage information for the switch commands used in this chapter, refer to the
Catalyst 4500 Series Switch Cisco IOS Command Reference and related publications at
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/index.htm.