Re: Reduce ARP Traffic

Tech-Archive recommends: Fix windows errors by optimizing your registry

STP is also a must for those of us running education networks where the kids
think it's fun to knock the network down by looping the ethernet. It's
apparently called an aggressive user base :-)

"Chris Patterson" wrote:

I agree with Phillip. This software vendor is trying to cop out.

I once had to t-shoot a dial in issue with a vendor. They first tried to
claim the possibility of our designated phone line was bad. I called them on
it and said, "Look I called Bell South and had them do a diagnostic on the
line, it is clean." There response was, "Well how do we know their
diagnostic was accurate?", "We know cause they are the freakin' phone
company!", "Well can we put a new cord between the modem and wall jack?", "I
did, brand new.", "Well how do we know it is good?' and on and on.

Back to STP the reason I was posting, Phillip is right, STP is only used if
you have 2 paths from one network devise, i.e. say 2 switches and a dual nic
server that is connected to each for redundancy. In this instance you have
to have STP or else you will have a loop.

Chris

"Bryan L" <blinton.nospam@xxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:OHX7HoWPGHA.648@xxxxxxxxxxxxxxxxxxxxxxx
Philip,

Thanks for the reply. You've confirmed my hunch that my network was too
small for those things to really have any affect. It's been a while since
had to remember anything about STP; is there any reason to turn it back
on? I'm running on a single subnet so I'm not routing between subnets. As
for ARP, I understood it to be a part and parcel of running an IP-ethernet
network, so I'm not too worried about that either.

The reason we're looking to network issues as possible causes is that
we've ruled out nearly everything else. I've spoken with other businesses
similar to or larger than ours running the same application, and although
a few had some initial issues with stability, they've been resolved and
are now pretty solid. To eliminate variations between my workstations, I
initially deployed them via a carefully configured sysprepped image. To
rule out any possibility that my system image was somehow the cause, I
wiped one workstation and did a clean, manual reinstall of the OS,
installing only the basic apps needed to test my theory. The user on that
workstation didn't see any reduction in errors. I'd consider some wierd
issue with hardware, but I have a few users on different model
workstations than the norm, and they have the same problems. Aside from a
core network infrastructure issue, the only other things I can think of
are a weirdly corrupt server install, incompatible/interfering software on
one of my servers, a unique group policy issue (I make extensive use of
GPOs), some hard-to-identify user behaviour, a malfunctioning node on my
network that randomly throws out nasty, malformed broadcast traffic (?!),
solar flares, nearby vampire activity, or Martha Stewart's stock
portfolio.

Once the packet sniffer is removed, they'll spend a week or so crunching
the data collected, then call me with a full report. I really hope they
DO find something wrong with my network (like the horizontal cabling; I've
wanted to rewire the office since I got here almost two years ago), just
so we can get some resolution on this problem. If they come up
empty-handed, we only have a few ideas left to test before we're tapped
out.

Thanks again for the reply, I'll keep you posted.

BJ


"Phillip Windell" <@.> wrote in message
news:uWEXDmUPGHA.2036@xxxxxxxxxxxxxxxxxxxxxxx
"Bryan L" <blinton.nospam@xxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:e4l0HGUPGHA.2888@xxxxxxxxxxxxxxxxxxxxxxx
We've migrated to a new version of our mission-critical application that
for
us has turned out to be very unstable. In an effort to troubleshoot the
problem, the vendor has been running a protocol analyzer on our network
for
a few days. We discovered we had a lot of Spanning Tree Protocol
traffic
generated by our relatively new GB switches, but we thought we found
where
to turn that off. His latest update confirmed this and had a new
observation:

"There was no sign left of the spanning-tree protocol. However there is
a
lot lf ARP request traffic. This may be reduced by updating the DNS
tables
and setting up a static host table in all workstations."

If he thinks the ARP requests are a problem then it is no wonder to me
that
he/they worte an unstabile Application. Ethernet requires ARP,..ARP is
supposed to be there just like you are seeing it. Spanning Tree is
supposed
to be there just like is was as well and you shouldn't have messed with
it.
Neither of these "mess up" anything. The App they wrote is unstabile
because that is how they wrote the thing resulting from the fact that
they
probably know very little about networking and the fact that they have
you
chasing STP and ARP packets around with a packet sniffer tends to prove
that
to me.

Finally, on a subnet of my size (fewer than 50 nodes), should I even
need
to bother trying to reduce ARP traffic? I have a hard time believing
it's
sufficient to create any kind of real broadcast storm, unless I'm either
being attacked from within (not likely) or something is failing.

No, you shouldn't have to worry about any of that and you can run 250-300
hosts before you have to worry about congestion caused by *normal*
IP/Ethernet Broadcasts (APR, STP, DNS, WINS, DHCP, etc). I do not think
there is anything wrong with your LAN,..period. I think they wrote a
lousey
Application and are trying to blame everything else because it doesn't
work
right. If there was a problem with the design of your LAN you would have
a
lot more things not working right than just their Application.

It seems to be typical of some programmers when they aren't quite sure
what
they are doing,..to want to change the environment to accomidate their
Application rather than write the Application correctly so it works in a
"normal" existing environment.

...and yes, I "held back" a little bit :-)

I don't have much patients for Vendors and their Applications in these
kind
of situations. I've had to fight those battles here as well.

--
Phillip Windell [MCP, MVP, CCNA]
www.wandtv.com
-----------------------------------------------------
Understanding the ISA 2004 Access Rule Processing
http://www.isaserver.org/articles/ISA2004_AccessRules.html

Troubleshooting Client Authentication on Access Rules in ISA Server 2004
http://download.microsoft.com/download/9/1/8/918ed2d3-71d0-40ed-8e6d-fd6eeb6cfa07/ts_rules.doc

Microsoft Internet Security & Acceleration Server: Guidance
http://www.microsoft.com/isaserver/techinfo/Guidance/2004.asp
http://www.microsoft.com/isaserver/techinfo/Guidance/2000.asp

Microsoft Internet Security & Acceleration Server: Partners
http://www.microsoft.com/isaserver/partners/default.asp

Deployment Guidelines for ISA Server 2004 Enterprise Edition
http://www.microsoft.com/technet/prodtechnol/isa/2004/deploy/dgisaserver.mspx
-----------------------------------------------------











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Relevant Pages

  • Re: Reduce ARP Traffic
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  • Re: Reduce ARP Traffic
    ... I once had to t-shoot a dial in issue with a vendor. ... Back to STP the reason I was posting, Phillip is right, STP is only used if ... server that is connected to each for redundancy. ... network, so I'm not too worried about that either. ...
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