Related Documents - Cisco Catalyst 4500 Series Software Configuration Manual

In-Service Software Upgrade (ISSU) on a VSS
on the other switch. If a peer device is connected to the VSS over an MEC that has links terminating in
both switches, that device will not experience a disruption of service during the software upgrade
process. This is illustrated in
Figure 5-10 Connecting a Peer Device to VSS to Avoid Service Disruption
Traffic on this non-MEC
Etherchannel will be
disrupted whenever
Switch #1 undergoes
a reboot during the
ISSU process.

Related Documents

Related Topic
Performing ISSU
Prerequisites to Performing ISSU
Before performing ISSU, you must meet these prerequisites:
•
•
•
Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
5-58
Figure
VSS
Switch #1
Traffic on this MEC link will not
be disrupted throughout the ISSU process.
Whenever one of the VSS switches undergoes
a reboot, the MEC member link goes down,
causing the link peer to send all traffic over
the surviving link.
Ensure that the current Cisco IOS XE version running in the system supports ISSU. Also ensure that
the target version supports ISSU.
In a Quad-Supervisor VSS setup, ensure that you copy the Cisco IOS XE image on the standby
supervisors of both the switches, from the VSS Active switch console, using the IOS copy command
so that the boot variable has a valid path to point to.
You can enter various commands on the switch to determine supervisor engine versioning and Cisco
IOS XE software compatibility. Alternatively, you can use the ISSU application on Cisco Feature
Navigator to determine this.
The type of the pre- and post-upgrade images must match precisely. Identical. ISSU is not supported
from a Universal_lite to a Universal image, or vice versa. ISSU is also not supported from a k9
image to a non-k9 image, or vice versa.
5-10.
VSS
Switch #2
Traffic on this link will be
disrupted whenever
Switch #2 undergoes a
reboot during the ISSU
process.
MEC
Document Title
Cisco IOS Software: Guide to Performing In Service Software
Upgrades
Chapter 5 Configuring Virtual Switching Systems