Cisco Catalyst 4500 Series - Page 352

7-10
Software Configuration Guide—Release IOS XE 3.6.0SG and IOS 15.2(2)SG
OL-30933-01
Chapter 7 Configuring the Cisco IOS XE In Service Software Upgrade Process
About Performing ISSU
After a switchover (NSF/SSO, not RPR), the standby supervisor engine takes over as the new active
supervisor engine (see Figure 7-6).
Figure 7-6 Switch Over to Standby Supervisor Engine
Line cards
Old
Active
Supervisor
Engine
NSF/SSO
Switchover
NSF/SSO
Switchover
Run new version
of Cisco IOS XE
the new active
New
Active
Supervisor
Engine
208665
Cisco IOS XECisco IOS XE
3.x.y.SG3.x.y.SG
Cisco IOS XE
3.x.y.SG
Cisco IOS XE
Cisco IOS XE
3.z.y.SG3.z.y.SG
Cisco IOS XE
3.z.y.SG