What is the difference between the IOS 12.2(55) and 12.2(58) versions?

[goyourmin]

hello !

i am reviewing IOS 12.2 SE version.

However, many of the 12.2 versions of the 12.2(53), 12.2(54), 12.2(55), 12.2(58), etc., are confusing.

What is the difference between IOS 12.2(55)SE and IOS 12.2(58)SE?

Q1. 12.2(55) has the latest update, but common sense dictates that 12.2(58) is the latest version because the number is higher? (e.g. functional part)

Q2. Can you find a roadmap for each of them 12.2?
- I can't find the difference between 12.2(55) and 12.2(58) on the CISCO homepage. Or should 12.2(55) and 12.2(58) be considered separate IOS?

I checked the link below, but I couldn't find any information about IOS 12.2(55)SE.
(The download homepage provides 12.2(55)SE. and 12.2(58) is not provided.)

link : https://www.cisco.com/c/en/us/support/ios-nx-os-software/ios-software-releases-12-2-se/products-release-notes-list.html

best regard,

[Kasun Bandara]

@goyourmin any specific hardware model are you looking to install these versions? its hard to find details because these versions are very old and end of life.

[goyourmin]

Thank you for your interest in me.
The hardware models I'm looking for are WS-C3750G-24TS-1U, WS-C2960-24TC-L. Since I am currently using an older version, I want to use the relatively recent version.

[Flavio Miranda · Accepted solution]

Hi

 Would be interesting first understand how the IOS name is created. This link would help you.

https://www.cisco.com/c/en/us/support/docs/ios-nx-os-software/ios-software-release-1513t/200095-Understanding-Cisco-IOS-Naming-Conventio.html 

[goyourmin]

This document provides me with very useful information. Thank you very much.
I couldn't find any functional descriptions for 12.2(55) and 12.2(58), but I think we can make a guess based on this document.

Based on the documentation, it seems that 12.2(58) has added more features than 12.2(55).

- IOS 12.2(55) and 12.2(58) seem to be released separately from each other regardless of whether there is a functional difference. Is that right?

Throttles
Cisco IOS Throttle is roughly a minor version number where some new features and bug fixes can have been added. For Cisco IOS the general rule of thumb is that new features are not added "mid-throttle". In other words, when new feature need to be added, they would be added when a new throttle is started.

[Flavio Miranda]

@goyourmin thats was the idea.

IOS 12.2(55) and 12.2(58) seem to be released separately from each other regardless of whether there is a functional difference. Is that right?

Yeah and I am afraid that the specifics will not be described by Cisco in any document.

[Ramblin Tech]

Any product old enough to run a 12.2 release is likely well past its End-of-Engineering milestone, so as a general rule, I would look at the latest release available for that specific platform that contains the feature set required for your deployment.  End-of-Engineering means no new bug-fix rebuilds will be forthcoming and the latest release contains all the bug fixes that will ever be available in that throttle. This is the case for both your WS-C3750G-24TS-1U and WS-C2960-24TC-L: they are not only past End-of-Engineering, but years past End-of-Support as well (no TAC troubleshooting or RMAs).

Products this old will not have had any new features added for quite some time, with only bug-fixes in the last several IOS releases.  The Release Notes contain lists of new PI & PD features and bug fixes added incrementally with each release, but the lists are not exhaustive.  That is, Cisco Product Management may have intentionally left out some new feature introductions and bug fixes from the Release Notes for business reasons.  Typically, there are enormous numbers of open and resolved caveats with each release, so the caveat list represents the PMs' best judgment as what to publicly disclose.

[goyourmin]

At this point, it is very difficult to know what features have been added to the change from 12.2(55) to 12.2(58).

Thank you so much for your answer.

[Leo Laohoo]

12.2(58)SE train is a short lived train because it is very unstable. 

12.2(55)SE and 15.0(2)SE train are universally acknowledged to be two trains that are stable and reliable.  

[goyourmin]

I was considering the IOS 12.2(58)SE because I guess that the 12.2(58)SE is a version with more features than the 12.2(55)SE. Even if IOS 12.2(55)SE has been updated until recently.

I think i should consider the IOS 15.0(2)SE you mentioned.

Oh, this 3750G model is not capable of version 15.

Thank you so much for letting us know.

[Leo Laohoo · Accepted solution]

No one, from Cisco, will openly admit a 3750G can support 15.0(2)SE train, particularly, 15.0(2)SE11.  It can and it will.  

Only the plain 3750 (FastEthernet access ports) can only support up to 12.2(58)SE.  

[Ramblin Tech]

Situations where a particular IOS release (or s/w feature, or optic, or h/w module, or ...) is not officially supported on a given SKU even though it appears to work just fine often comes down to devtest resources: Cisco Engineering and Product Marketing have decided to prioritize test resources elsewhere.  Extensively testing new s/w or h/w features against a SKU takes significant effort to plan and execute, efforts that might provide a better ROI if applied to another project (and Cisco is definitely a numbers-driven company).

Customers are free to load unsupported IOS releases, turn on unsupported features, or plug in unsupported h/w pluggables, but if the Business Unit/Entity that is responsible for the platform says it is "unsupported", then TAC cannot support that configuration. If TAC concludes that a customer's issue may be related to the unsupported configuration, they can only tell the customer that a supported configuration must be implemented before they can proceed any further with troubleshooting.

[Leo Laohoo]

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@Ramblin Tech wrote:
Cisco Engineering and Product Marketing have decided to prioritize test resources elsewhere.  Extensively testing new s/w or h/w features against a SKU takes significant effort to plan and execute, efforts that might provide a better ROI if applied to another project (and Cisco is definitely a numbers-driven company).

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I totally disagree with this.  Cisco does not have a "test" regime.  Zero.  Nadda.  

Cisco has stopped testing software releases way back 2015 (maybe earlier).  Had Cisco been able to even do basic tests, i. e.  load the firmware into an appliance (and not IoL), a lot of the bugs we see today would never have seen the light of day. 

2nd paragraph does not apply here.  3560/3560G/3560E/3560X and 3750/3750G/3750E/3750X are already end-of-support.  TAC will not touch any cases related to them.  

[Ramblin Tech]

Lest anyone takes your tongue-in-cheek statement seriously about Cisco not testing software releases since before 2015, let me state unequivocally here that Cisco does indeed have formal processes for testing their software releases.  CFDs (Customer Found Defects, as opposed to defects found during devtest) is a metric that Cisco tracks for software releases, with Engineering management continually telling everyone inside the company that they have a new plan to reduce CFDs.  If you think the number of CFDs is high, you should see the number of defects found during devtest!

Do the continually rolled-out new plans reduce CFDs to near zero?  Of course not, so a new round of initiatives is rolled out to tackle the s/w quality problem that every customer complains about year after year. 

You are absolutely right about TAC not supporting products that are past their End-of-Support date, but a customer should still be aware that loading in an unsupported IOS release on EoS h/w may yield hard to troubleshoot issues later, even if the h/w initially boots without a problem.

[Leo Laohoo]

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@Ramblin Tech wrote:

Lest anyone takes your tongue-in-cheek statement seriously about Cisco not testing software releases since before 2015, let me state unequivocally here that Cisco does indeed have formal processes for testing their software releases.  CFDs (Customer Found Defects, as opposed to defects found during devtest) is a metric that Cisco tracks for software releases, with Engineering management continually telling everyone inside the company that they have a new plan to reduce CFDs.  If you think the number of CFDs is high, you should see the number of defects found during devtest!

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I stand by my statement.  I have received confirmation (from Cisco staff) that some of the bugs we have discovered because the codes were not tested "properly" prior to release.