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Re: Using TTCP to generate a specific amount of traffic in bps posted 11/25/2004
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Thanks John,

It's always good to have options and know how to use them.

Happy Thanksgiving,

Tim
----- Original Message ----- 
From: "John Wong" <johnwk@xxxxxxxxxxxxxx>
To: "ccie2be" <ccie2be@xxxxxxxxxx>
Cc: "Group Study" <ccielab@xxxxxxxxxxxxxx>
Sent: Wednesday, November 24, 2004 5:44 PM
Subject: Re: Using TTCP to generate a specific amount of traffic in bps


> 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@xxxxxxxxxxxxxx>
> > To: "ccie2be" <ccie2be@xxxxxxxxxx>
> > Cc: "Brian McGahan" <bmcgahan@xxxxxxxxxxxxxxxxxxxxxx>; "Group Study"
> > <ccielab@xxxxxxxxxxxxxx>
> > 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@xxxxxxxxxxxxxxxxxxxxxx>
> >>>To: "ccie2be" <ccie2be@xxxxxxxxxx>; "Group Study"
> >
> > <ccielab@xxxxxxxxxxxxxx>
> >
> >>>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@xxxxxxxxxxxxxxxxxxxxxx
> >>>
> >>>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@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] 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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