[c-nsp] IOS XR 4.3.0 or 4.3.1

[Jared Mauch]

On May 22, 2013, at 8:50 AM, Adam Vitkovsky <adam.vitkovsky at swan.sk> wrote:

> Shane, Jared, 
> I guess we all have been told by our SEs that the 4.2.3 is the safe harbor. 
> So I'm really curious what bugs made you abandon 4.2.3 and made your choice
> to rather go with 4.3.x instead. 
> Would you please share the bug IDs or short description of the problems
> please?
> 
> As the only one I'm aware of -that has a fix in 4.3.1 is the manual
> Remote-LFA functionality using te-tunnels:
> http://www.cisco.com/en/US/docs/routers/asr9000/software/asr9k_r4.2/general/
> release/notes/reln_423a9k.html#topic_AFBC45CA95C34828AFFF712B6107E883

I'm not going to go into all our environment and defects in public, but I do try to
share our experiences for the benefit of the community.

If you are on 4.2.x, 4.2.3 is the best place to be.  If you are picking a path forward,
you should be looking at 4.3.1.  We still have some issues that are not fixed
in 4.2.3 and 4.3.1 and we are waiting for those SMUs to be released.

Some of these are specific to our configuration, some are related to how we deploy
and operate our network.  Many of the things we consider operationally impacting
cisco enjoys the leisure of calling cosmetic as they don't operate the equipment.
We need things like RANCID to collect accurate inventory.  These don't work well
in 4.2.x but are fixed in 4.3.x (eg: CSCuc67718)

I've had another case open since February without resolution on a similar issue
using Cisco optics and they still haven't been able to provide a fix in 4.2.x
but the issue is fixed in 4.3.x.  

IMHO, the only real reason to run 4.2.x is if you like troubleshooting
bugs that are already resolved in a future release :)  I don't have that full luxury.

We have a number of outstanding SMU requests.  If you're a Cisco employee and
reading this, I can provide some reference lists in private should you be interested.

- Jared