4500x Upgrade through ISSU

[shaharshad]

Hi,

I have two 4500x switches contected  via VSS. I am planning two upgrade their IOS. It seems upgrade via ISSU is bit tricky. Can someone guide which method i should follow (With or without ISSU) detailed steps?

Thanks

[Venkatesh Perumal]

https://supportforums.cisco.com/discussion/11944231/upgrading-ios-4500x-switches

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/XE3-5-0E/15-21E/configuration/guide/config/issu.html#pgfId-1130462

http://cisco-ts-cheatsheet.blogspot.in/2014/10/issu-downgradeupgrade-steps-on-4500x-vss.html

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/15-1-2/XE_340/configuration/guide/config/vss.html

[shaharshad]

Thanks Venperum,

I have gone through these already but Cisco makes it more confusing:)

[Reza Sharifi]

Hi,

If you can upgrade during a maintenance window, I would do it that way, as it only requires one reboot and both devices can be upgraded in less than 15 minutes. ISSU usually works when you upgrade from one minor release to another and not from one major release to another.  It also takes longer, because you would need to upgrade one switch at a time and reboot.

 HTH

[shaharshad]

Hi Reza,

Its a major upgrade , with reference to our  other discussion I m moving from M to K9. So you suggest do it normal and down the VSS interface?

[Reza Sharifi · Accepted solution]

Hi,

Yes, I suggest the following:

1-Load the new IOS to both primary and backup switches

2-Change the boot variable so the switches can boot from the new IOS

3-Save all you changes

4-Reboot both chassis.

Once the switches are rebooted, verify VSS is working and the switches are running the new version. The boot process will not take more than 15 minutes max.

HTH

[shaharshad]

Thanks Reza,

You always being very helpful. 

[Reza Sharifi]

Hi,

If the information is helpful to you, please rate and mark the post as answered so others in the forum can benefit from it.

Thanks,