Network scan tool/appliance horror stories

Ryan Malayter malayter at gmail.com
Tue Oct 30 05:04:21 UTC 2012


On Oct 29, 2012, at 3:55 PM, "Rutis, Cameron" 
>  
> 6) large stacks of 3750s (six or more members) have issues around CPU during certain SNMP commands (I want to say some sort of getbulk type of command)
> 
> The first four were pretty minor although #3 could generate a lot of calls to the support center.  #5 was a big deal due to the nature of the application.  #6 was impactful because we dropped routing neighbors for about 10 seconds but this was a couple of years ago so may have been an old IOS bug.

Saw the same. All of our 3750 stacks (which are small) committed suicide during a trial of Foglight. We had discovery timings turned way down, but it still caused a reload on a mix of the last supposedly really stable releases of 12.x.

Not confidence inspiring. TAC was useless and suggested a v15 upgrade despite no known fix. The proposed v15 upgrade sent our lab boxes into continuous reload unless you broke the stack and manually wiped each switch. Oh, and port 28 was invisible on each switch after upgrade, and Gi2/0/28 would throw a syntax error. Wait for new releases, lather, rinse, repeat.

Total time to resolution in production was several man-weeks on our side, and a few months calendar time, all because the discovery scan revealed how great a "software company" Cisco has become.


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