perfSONAR User Q&A and Other Discussion

[Zhi-Wei Lu <>]

Hi all,

I am reviving my old thread as I am progressing more on this TWO NICs setup.

I have configured two NICs with Linux policy routing, with one NIC as a 
primary, currently performing regular tests with bwping, bwtraceroute, 
and bwctl, while the other NIC was configured for powstream (one way 
latency tests).  I manually configured with the configure file in
/opt/perfsonar_ps/regular_testing/etc/regular_testing.conf

After each <test>, I manually and explicitly added (rather than using 
implied "default" interface, problematic in a multi-NICs situation)

local_interface eth0
for bwping, bwtraceroute, and bwctl

local_interface eth1
for latency tests (powstream)

I am wondering how I can modify my configuration files to advertise 
INCOMING powstream only on ip address corresponding to eth1 and other 
tests to eth0.  Currently, the web GUI advertises all tests on both 
interfaces.

Thank you very much for your insight and have a wonderful New Year!


On 07/30/2014 12:38 PM, Trey Dockendorf wrote
> That's a problem with Linux I believe.  Having two interfaces on the same 
> subnet will result in both IPs responding but if you do an arping to each IP 
> you will likely see that the same MAC address is hit every time.  I do not 
> know the right way to fix this, so I've always avoided that situation of 
> configuring two NICs on the same subnet.
>
> RedHat has knowledge base articles regarding this but it's for subscribers 
> only.  Here's something similar but not requiring a subscription, 
> http://z-issue.com/wp/linux-rhel-6-centos-6-two-nics-in-the-same-subnet-but-secondary-doesnt-ping/
>
> Not sure if that's the problem your describing.
>
> - Trey
>
> =============================
>
> Trey Dockendorf
> Systems Analyst I
> Texas A&M University
> Academy for Advanced Telecommunications and Learning Technologies
> Phone: (979)458-2396
> Email: 
>
> Jabber: 
>
>
> ----- Original Message -----
> > From: "Zhi-Wei Lu" 
> > <>
> > To: "Daniel Doyle" 
> > <>
> > Cc: 
> > ,
> >  "Pulak K Chowdhury" 
> > <>
> > Sent: Wednesday, July 30, 2014 1:56:23 PM
> > Subject: RE: [perfsonar-user] tips for One way latency and bw test on 
> > separate NICs on perfSonar 3.4rc2
> >
> > Hi Daniel,
> >
> > Thanks for the tip and I have found it configuration in the web gui.
> >
> > However, I am stuck again!  I started the system with one configured
> > NIC and scheduled "owamp" test.  Later, I enabled the second NIC on
> > the same subnet, now the "Throughtput/Latency Graphs" won't
> > displayed at all, a perpetual spinning circles goes around (even
> > after I disabled the second NIC).
> >
> > If I have two NICs in the the same host on the same subnet, will the
> > outgoing tests use the first interface only (default route on the
> > default NIC)?  While both interface were up, the "local services"
> > show all tests running on both NICs, how can I configure the
> > incoming tests for individual NIC.  With two NICs on the same
> > subnet, the incoming test comes the second NIC, but the outgoing
> > packets could be sent out on the first NIC, is that right?
> >
> > Thank you.
> >
> > Zhi-Wei Lu
> > IET-CR-Network Operations Center
> > University of California, Davis
> > (530) 752-0155
> >
> > -----Original Message-----
> > From: Daniel Doyle 
> > [mailto:]
> > Sent: Wednesday, July 30, 2014 6:34 AM
> > To: Zhi-Wei Lu
> > Cc: 
> > ;
> >  Pulak K Chowdhury
> > Subject: Re: [perfsonar-user] tips for One way latency and bw test on
> > separate NICs on perfSonar 3.4rc2
> >
> > Zhi-Wei,
> >
> > This is configurable in the same place as you configure all the rest
> > of the test parameters, underneath "Toolkit Administration" on the
> > left in the section "Configure Tests".
> >
> > There is now a new field called "Interface" under the Test Parameters
> > section of a test that defaults to "Default" which was the old
> > behavior. You can change this to instruct the test to use a specific
> > interface instead. All previously configured tests should have
> > "Default" set as their Interface option when upgrading.
> >
> > Hope that helps.
> >
> > -Dan
> >
> > On Jul 30, 2014, at 1:47 AM, Zhi-Wei Lu 
> > <>
> >  wrote:
> >
> > > Hi all,
> > >
> > > I have successfully installed perfSonar 3.4rc2 recently and I heard
> > > that it is now possible to configure owamp and bw tests on two
> > > separate NICs, I would love to learn how I can configure perfSonar
> > > to accomplish two NIC set up.
> > >
> > > Thank you very much for your help.
> > >
> > > --
> > > Zhi-Wei Lu
> > > IET-CR-Network Operations Center
> > > University of California, Davis
> > > (530) 752-0155
> > Dan Doyle
> > GlobalNOC Software Developer
> > 1-812-856-3892

--
Zhi-Wei Lu
IET-CR-Network Operations Center
University of California, Davis
(530) 752-0155