VSS 4506E with Sup 7E Software Upgrade

[kelvin_ho]

I got 2 x C4506E (with Sup7E)  in VSS going to upgrade from software version 3.4.8.SG to 3.8.8.E

1.) I would like to know the best procedure to reduce the downtime.

2.) While i am reloading the active Supervisor Engine, is it all the line card in this primary chassis will be failed to work and forwarding traffic? Since there are some devices only connected to the primary chassis only. would like to know the impact time

[Mark Malone]

Hi
if you have devices that are considered orphan and on 1 switch yes they will take a hit, each switch reloads

ISSU is least downtime but from experience it can fail more often than work , a hard reboot will be quicker and cleaner i would just take the hit and plan for an outage

Impact time depends on the network itself there is no 1 time fits all , switch itself can take up 20 minutes to upgrade , stp to form , the amount of devices connected to come up ,features in place etc all contribute to the time , give yourself plenty of time at least 1 hour to the VSS upgrade

this shows the ISSU method , same concept commands for your version , feature hardly changes even between platforms

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/XE3-8-0E/15-24E/configuration/guide/xe-380-configuration/issu_XE.html

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/12-2/31sga/configuration/guide/config/issu.html#wp1091552%0A

[Leo Laohoo]

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@kelvin_ho wrote:

1.) I would like to know the best procedure to reduce the downtime.

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Read the Release Notes for 3.8.X very carefully.
It is not possible to upgrade the IOS unless the ROMMON is upgraded first.

The ROMMON upgrade alone takes about 40 minutes.