When to upgrade an IOS

[alanbcameron]

I have two 6509's each with an RSM. The RSM is running IOS 12.1, 121-2.E to be exact. The supervisor (Sup1a) is running version 6.1(4).

Should these be upgraded as a matter of course, or, are they fine as is ?

[stomasko]

Upgrades include bug fixes as well as new features and also patch security holes. You need to balance the cost of the upgrades with these facts and decide based on that.

Steve

[acameron12]

Okay, but, given what I have in place now. Should an upgrade be considered as a matter of course ? I understand that upgrading for the sake of upgrading is not prudent.

[m.mcconnell]

I find that upgrading to avoid bugs is well worth the work and you are running old software.

CatOS

The oldest 6.1(4) version available is 6.1(4b) - meaning there were bug fixes to what you are running and what you are running has been pulled from download.

IOS - MSFC

The version you are running there has also been pulled from download for whatever reason - usually due to bugs.

I would think an upgrade is in order, just make sure you have enough memory installed before performing the upgrade. I believe the Sup1a - at least the early ones - came with 64MB RAM by default.

-Mark

[acameron12]

Thanks Mark, I will make this part of my upgrade plan. Is version 7.6(15) a good upgrade option ?

[m.mcconnell]

Personally I would consider 7.6(15) to recent. For the Sup1a and Sup2 I use this methodology for picking code for core 6500s.

It should work with the memory installed on the switch - unless I absolutley need some newer capabilities. Then a memory upgrade is in order and that can be ugly.

It should be at least 3 months old. 3 months will usually shake out major bugs and if major bugs exist the image will pulled from download.

I run a search in the bug tool kit before uploading to make sure there are no known bugs that affect features that are currently in use.

Picking code for the Sup1a and SUp2 is more of an art than a science. For the Sup720 just get the newest and plan for bugs and upgrades at least quarterly.

-Mark

[Prashanth Krishnappa]

I would stick with 6.4(20) since you have a Sup1. Note that 7.6(x) releases need 128MB DRAM. 6.4(20) is general deployment and stable but also end of life.

[acameron12]

Understood. I have confirmed I have 64mb of DRAM on my supervisors.

[Marvin Rhoads]

For any network infrastructure, one should baseline and periodically evaluate the running software. Consistency across like platforms and being on a supported current release are two good criterion one should meet (besides the obvious of having a release that meets your needs). Any inconsistency should be for validated reasons that are documented and revisited at the next review cycle.

New releases include not just bug fixes, but also features (the whole purpose of Cisco "T" (technology) train software releases).

One other thing to consider in the specific situation you describe is the possibility of moving off of hybrid (CatOS on the Sup + IOS on the MSFC) to a native IOS image. Many folks find the native integration of the switchs layer 2 and layer 3 functionality to be a more intuitive configuration.