About Performing ISSU
An ISSU-capable switch consists of two supervisor engines (active and standby) and 200 or more
linecards. Before initiating the ISSU process, copy the Cisco IOS XE software into the file systems of
both supervisor engines (see
Note
In the following figure, Cisco IOS XE 3.x.y SG represents the current version of Cisco IOS XE 3.z.y SG
represents the image you are migrating to.
Figure 8-4
Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
8-8
Chapter 8
Figure
8-4).
Copy New Version of Cisco IOS XE Software on Both Supervisor Engines
Copy new version
of Cisco IOS XE
on active and standby
Supervisor Engines
Cisco IOS XE
Cisco IOS XE
Cisco IOS XE
3.x.y.SG
3.x.y.SG
3.x.y.SG
Cisco IOS XE
Cisco IOS XE
Cisco IOS XE
3.z.y.SG
3.z.y.SG
3.z.y.SG
Active
NSF/SSO
Supervisor
Supervisor
Engine
Line cards
Configuring the Cisco IOS XE In Service Software Upgrade Process
Cisco IOS XE
Cisco IOS XE
Cisco IOS XE
3.x.y.SG
3.x.y.SG
3.x.y.SG
Cisco IOS XE
Cisco IOS XE
Cisco IOS XE
3.z.y.SG
3.z.y.SG
3.z.y.SG
Standby
Engine