Network management software with high detailed traffic report

Tassos Chatzithomaoglou achatz at forthnet.gr
Mon Nov 22 16:56:12 CST 2010


Does "service counters max age" help in any way?*
*According to Cisco, setting it too low might upset the snmp counters.*

*

--
Tassos


Jon Lewis wrote on 23/11/2010 00:19:
> On Mon, 22 Nov 2010, Brandon Ross wrote:
>
>> On Mon, 22 Nov 2010, Nick Hilliard wrote:
>>
>>> some do, some don't.  For example, sup720 snmp counters are updated 
>>> every 9 seconds, while the "show interface" counters are updated 
>>> every 30 seconds.
>>
>> That is most certainly NOT true.  The 'show interface' counters 
>> update at least once a second.  Perhaps you are thinking about the 
>> rate counters that are often _configured_ to use the last 30 seconds 
>> of data to compute the average but also update much more often than 
>> every 30 seconds (and default to a 5 minute average).
>
> I didn't think it was true either...but after reading Nick's message I 
> checked a X6408A interface on one of our sup720's running "relatively" 
> recent code (SXI1), and there definitely is some time between updates 
> both the packet counters and the time averaged rates.
>
> Just repeating the command and looking at my watch, I'd say Nick is 
> right. It's easy to test yourself.  Pick an int, and repeat "sh int 
> <int name> | inc packets.  The numbers really don't change but every 9 
> seconds or so. Same goes for the avg numbers...mine are set to 30 sec 
> load interval, and they only change every ~9 seconds.
>
> This does vary by platform.  3550 swiches and 7200 routers both seem 
> to update the counters about 1/s.  Maybe the delayed updates are just 
> a 6500 thing.
>
> ----------------------------------------------------------------------
>  Jon Lewis, MCP :)           |  I route
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>




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