ISR4431/K9 upgrade issue

[Rps-Cheers]

HI Expert，

We plan to do image upgrade on ISR4431/K9 from version 16.3.4 to 16.9.3. Is there any precautions ? I also have another problem that is the Front Panel 4 ports Gigabitethernet Module named ISR4431-X-4x1GE how to work If ISR4K ESP not work or down?

Thanks

[Leo Laohoo]

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@Rps-Cheers wrote:

We plan to do image upgrade on ISR4431/K9 from version 16.3.4 to 16.9.3. Is there any precautions

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Has anyone read the Release Notes of 16.9.3? 

Is this router going to do any NAT?  If it is, has anyone checked out CSCvo36188?

[Giuseppe Larosa]

Hello Leo,

thanks for your advice

the bug description says CG-NAT that should be Carrier Grade NAT and not simple NAT.

However, the bug says that it is enough to clear nat entries to cause a router crash !!!!!!!!!!!!!!

The list of affected platforms include multi layer switches like C3850 that does not support NAT at all.

I agree that if the router is configured for NAT it would be better to think carefully before upgrading to this image.

Best Regards

Giuseppe

[Leo Laohoo]

Thanks Giuseppe.
I don't understand why a "re-build" of 16.9.3 hasn't been released with a fix of the bug.

[Giuseppe Larosa]

Hello Leo,

I don't know if it is fresh information, in the bug page in the list of fixed in releases reports a 16.9.(3.59) that looks like a patch for 16.9.3

Hope to help

Giuseppe

[Leo Laohoo]

Not sure about that. Ever since Cisco has released 3.X.X and 16.X.X the meaning of the versions in "Known Affected Versions" and "Fixed Versions" can mean anything. "16.9(3.59)" could mean a patch. It could also mean it is an internal (beta/open beta) version. I have come across several bugs that have, for example, 3.6.9 mentioned several times in the "Known Affected Versions" &/or "Fixed versions".
Cisco Bug IDs are becoming unreliable nowadays that I simply don't have confidence in them anymore.