Help....Cisco switch 4506 IOS Upgrade

[Ismail Shakbodin]

I plan to upgrade IOS for Cisco switch 4506. I have two pair of 4506 act as core switch, need to know whether is it ok during the upgrade we running different IOS. For example, Switch A running IOS 12.1.1 and Swwitch B running IOS 14.1.1.

Any issue if we have differrent IOS during upgrade?

[Leo Laohoo]

Lack of information.  But unless you are running VSS, you can have two chassis running HSRP, for example, and running different IOS.   The only thing to consider is that both chassis should have the same Feature Set.

[Ismail Shakbodin]

We didnt running VSS, we only have single SUP.

HSRP running on both 4506,need to know any impact to the traffic if we have two different IOS between two 4506?

Any best practise to do IOS upgrade with single SUP?

[Leo Laohoo]

No significant impact with two switches running different IOS. 

Best Practice:  

• Backup your config and VLAN database. 
• Arrange for a 30 minutes outage. 
• Make sure the IOS file is not corrupted by comparing the MD5 has value of the file you've downloaded against what's found in the Cisco website.
• Read the Release Notes and understand the cavaets and open bugs.

[Ismail Shakbodin]

Can we running separate IOS for another 24 hour?

any documentation that support your statement bro or any link?