Cisco 4500x ISSU with having Supervisor 1 only

[Adnan Khan]

Hi I want to upgrade my 4500X-32 which has Supervisor 1 (virtual slot 1) on both Switches and

both switches are in VSS mode.

ROM: 15.0(1r)SG11

IOS-XE Version (Current)              3.7.1E

IOS-XE Version (Target)                3.8.6E

I want to perform ISSUE upgrade. Can anyone give steps to perform ISSUE with minimum disruption and how much will be the downtime almost exaclty?

Regards,

[balaji.bandi]

Here is the steps for the ISSU.

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

Catalyst 4500/4900 series ISSU compatibility matrix
http://docwiki.cisco.com/wiki/Catalyst_4500/4900_series_ISSU_compatibility_matrix

We had some issue with 1 or 2 kits, i could not able to perform the ISSU, had small downtime to recover that.

If you not familiar with ISSU upgrade, you can do manual upgrade in  change window with Service downtime accepted with business.

Steps for manual upgrade : (always check the upgrade matrix and compatible matrix).

1. Always take backup of the running config / Old Image - in case required to restore.

2. Copy backup configuration and OLD Image to TFTP / Flash.

3. Always have access to console and physical access to kit when you performing the upgrade.

4. Copy the new IOS to Active and Stanby Unit. (always compare MD5 against with cisco site).

5  Configure the  boot variable string with  new IOS.

6. Config register 0x2102

7. Write the configuration

8. Reload or Reboot 

Always connect the Console cable and keep monitor the logs and capture the logs in case if any issues encounter, so you can analyse the logs to see what went wrong ? and easy remediation to mitigate the issue.

[Leo Laohoo]

Make sure you read the Release Notes.

[Adnan Khan]

Thank you all. Can't we use "issu changeverion" command to upgrade IOS in case of single SUP on both switches?

[Reza Sharifi]

Hi,

There are the available commands when running 3.6.5

ISSU commands
abortversion abort ISSU process
acceptversion accept new IOS version, new Active
changeversion Upgrade Active/Standby with new IOS version without user interaction
commitversion commit IOS version on Standby
loadversion load new IOS version on Standby
runversion run new IOS version on Standby and make it Active

Overall ISSU can be more painful than helpful.  If you have a maintenance window and can reboot both chassis at the same time, it is much easier. The reboot time is about 5 minutes for the x series.

HTH