From: John Wong (johnwk@unimelb.edu.au)
Date: Wed Nov 24 2004 - 19:44:46 GMT-3
Tim,
As what Brian have mentioned, you'll need to combine this with
shaping/policing to get the desired bandwidth. One thing good
about using this vs ping flooding is that you can generate TCP or
UDP traffic on any port (as long as both sides have been setup
for this). Also, it might be possible to affect the bandwidth
slightly by adjusting the TTCP parameters (not 100% sure how though).
So I see the options possible for you to generate traffic are :-
- extended ping (ICMP only)
- TTCP (TCP & UDP)
- SAA/RTR (RTP)
Slap in a shaper/policer and you're all set.
Cheers.
ccie2be wrote:
> Hey John,
>
> I looked at the documentation at the link you included and it seems to me
> that this tool is good for determining what bandwidth was used after the
> fact.
>
> I don't see a way to specify the bandwidth to be used beforehand.
>
> For example, how would I use this tool to generate exactly 33kbps of traffic
> between 2 routers?
>
> Thanks, Tim
>
>
> ----- Original Message -----
> From: "John Wong" <johnwk@unimelb.edu.au>
> To: "ccie2be" <ccie2be@nyc.rr.com>
> Cc: "Brian McGahan" <bmcgahan@internetworkexpert.com>; "Group Study"
> <ccielab@groupstudy.com>
> Sent: Wednesday, November 24, 2004 8:56 AM
> Subject: Re: Using IOS to generate a specific volume of traffic
>
>
>
>>Hi Tim,
>>
>>How about the hidden TTCP command? Check out
>>http://www.cisco.com/warp/public/471/ttcp.html
>>
>>Cisco ported this darn useful tool from the UNIX
>>world (among other things, like mrinfo, etc..).
>>
>>Below is a sample of how it looks like.
>>
>>R6#ttcp
>>transmit or receive [receive]: tr
>>Target IP address: 10.0.0.1
>>perform tcp half close [n]:
>>send buflen [8192]:
>>send nbuf [2048]:
>>bufalign [16384]:
>>bufoffset [0]:
>>port [5001]:
>>sinkmode [y]:
>>buffering on writes [y]:
>>show tcp information at end [n]:
>>
>>ttcp-t: buflen=8192, nbuf=2048, align=16384/0, port=5001 tcp -> 10.0.0.1
>>%Connect failed: Connection refused by remote host
>>
>>
>>Hope this helps.
>>
>>
>>ccie2be wrote:
>>
>>>Brian,
>>>
>>>That sounds like an excellent idea. Thank you.
>>>
>>>Out of curiosity, why would I shape rather than police on the downstream
>>>router?
>>>Does it make a difference? Actually, my hunch is that either would work
>
> for
>
>>>this purpose, do you agree?
>>>
>>>Thanks, Tim
>>>
>>>----- Original Message -----
>>>From: "Brian McGahan" <bmcgahan@internetworkexpert.com>
>>>To: "ccie2be" <ccie2be@nyc.rr.com>; "Group Study"
>
> <ccielab@groupstudy.com>
>
>>>Sent: Tuesday, November 23, 2004 2:25 PM
>>>Subject: RE: Using IOS to generate a specific volume of traffic
>>>
>>>
>>>Tim,
>>>
>>>You could do extended ping with a timeout of 0 and then shape
>>>the outbound interface to your desired rate. This would have to be done
>>>downstream of your QoS config you're trying to test.
>>>
>>>Brian McGahan, CCIE #8593
>>>bmcgahan@internetworkexpert.com
>>>
>>>Internetwork Expert, Inc.
>>>http://www.InternetworkExpert.com
>>>Toll Free: 877-224-8987 x 705
>>>Outside US: 775-826-4344 x 705
>>>24/7 Support: http://forum.internetworkexpert.com
>>>Live Chat: http://www.internetworkexpert.com/chat/
>>>
>>>
>>>
>>>
>>>>-----Original Message-----
>>>>From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf
>>>
>>>Of
>>>
>>>
>>>>ccie2be
>>>>Sent: Tuesday, November 23, 2004 12:24 PM
>>>>To: Group Study
>>>>Subject: Using IOS to generate a specific volume of traffic
>>>>
>>>>Hi guys,
>>>>
>>>>Is there a tool within IOS that can be used to accurately generate a
>>>
>>>given
>>>
>>>
>>>>amount of traffic?
>>>>
>>>>For example, suppose I want to test a MQC shaping or policing
>>>>configuration
>>>>and I want to generate a continuous stream of traffic at 65k to see
>>>
>>>what
>>>
>>>
>>>>happens when the cir is 64k. Is there a way to do this ?
>>>>
>>>>I know that by using ping and setting the packet size and repeat count
>>>
>>>I
>>>
>>>
>>>>can
>>>>generate traffic, but it seems that using this method doesn't
>>>
>>>translate to
>>>
>>>
>>>>a
>>>>specific rate.
>>>>
>>>>TIA, Tim
>>>>
>>>>
>>>
>>>_______________________________________________________________________
>>>
>>>
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>>>
>>>
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>
>
> _______________________________________________________________________
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