RE: multicast problems
Hi Kevin, all
Thanks for the quick response and asserting my assumptions. I usually do
these scenarios, and when they fail then I verify them with the authors.
Here are more unicast & multicast issues (still under previous env, i.e.
v.1.7 under WIN32)
1. Why does the CPU max out (100%) at the client (iperf -c host/ip)?
Actually this happens even in unicast. It would have made sense to me if it
were at the listening side (server).
2. Can I run/install two servers as services on different ports? for example
$iperf -s -u -p 5001 -D -o out01
$iperf -s -u -p 6543 -D -o out05
knowing that later the services would be removed with
$iperf -s -u -p 5001 -R
$iperf -s -u -p 6543 -R
When I tried that I just got the first one (out01) on port 5001. I tried a
quick trick (I don't know how services run under win32, yet!) like
$copy iperf.exe iperf1.exe
$iperf -s -u -p 5001 -D -o out01
$iperf1 -s -u -p 6543 -D -o out43
Looks like it works (got out43) but the (-R) killed both which is not what I
want (timing issues)
3. I am assuming it is OK to use --len & --bandwitdh as options on the same
cmd, right?
4. Referring to bullet #3 (the second one) on my previous email (shown
below), Can I run a duplicate scenario besides the original but on a
different port, in other words can I do the following on the same PC with
one NIC (trying to get two parallel media streams out, one on 5009 and the
other at 6543)
$perf -s -u -p -P 1 5009 -B 239.200.56.51
$iperf -s -u -P 1 -p 5009 -B 239.200.56.55
$iperf -u -b 1K -p 5009 --ttl 5 -t 10 -c 239.200.56.60
$perf -s -u -P 1 -p 6543 -B 239.200.56.51
$iperf -s -u -P 1 -p 6543 -B 239.200.56.55
$iperf -u -b 1K -p 6543 --ttl 5 -t 10 -c 239.200.56.60
Thanks,
Yasir
-----Original Message-----
From: Kevin Gibbs [mailto:kgibbs --at-- ncsa.uiuc.edu]
Sent: Thursday, October 23, 2003 5:18 PM
To: Sinada, Yasir
Cc: iperf-users --at-- dast.nlanr.net
Subject: RE: multicast problems
> >From: "Sinada, Yasir" <Yasir.Sinada --at-- Marconi.com>
> >To: "'dast --at-- nlanr.net'" <dast --at-- nlanr.net>
> >Subject: multicast problems
> >Date: Wed, 22 Oct 2003 19:57:17 -0400
> >
> >Hi,
> >I am using iperf version 1.7 on WIN32 platform. I had these issues with
the
> >multicast:
> >1. What is the proper order in starting? Is it client first then servers
or
> >vice versa?
With Iperf, servers should always be started before clients. Servers need
the time to set up and start listening before a client attempts a
connection.
> >2. Does the -P (--parallel) work with the -B option for multicast
servers?
The -P on the server side limits the number of incoming connections
handled. Unfortunately WIN32 has a HORRIBLE UDP implementation which
forces WIN32 UDP servers to only be able to handle one connection at a
time. So if you have only one stream flowing at any given time then the -P
works fine and will close the server after the given number of
connections.
> >3. Does the -o option work without the -D option? I want to use it
instead
> >of redirecting the output ( .. > outputfile)
At this time no. The -o was added for use with the -D, and implemented in
that narrow outlook. I was not here when WinService was added to Iperf but
I may change that behavior in a future version. It would also be nice to
have a portable version of the -o instead of the WIN32 only version we
have now.
> >3. Can I bind (-B) to 2 or more different multicast addresses on the same
> >port, on the same interface (NIC) while sending to a third multicast on
the
> >same port, in other words can I do the follwing from 1.1.56.18 with only
one
> >NIC (of course these addresses are not the actual ones :o)
> >>iperf -s -u -p 5009 -i 1 -B 239.200.56.51
> >>iperf -s -u -p 5009 -i 1 -B 239.200.56.55
> >>iperf -u -b 1K -p 5009 --ttl 5 -t 10 -c 239.200.56.60
There should be no reason why this wouldn't work. Be sure however that
there is only ONE client per Multicast address when using WIN32 servers
because of the previously mentioned junkie WIN32 UDP support. I see you
have realized the need for the --ttl option, make sure that the value is
high enough to reach your servers (but I am guessing you have that under
control =-).
Kevin
PS: Thanks for the extremely well written and informative questions. It is
nice not to have to guess what people are trying to do or how they are
trying to do it.