Troubleshooting TCP performance tutorial
joe at nethead.com
Fri Sep 17 20:09:45 CDT 2010
Spendy but looks good. I'll have to pick it up when the next
consulting check comes in. Thanks! I was sad to see that Eric Hall's
book was out of print. At least cheap used copies are available. I
forgot my copy a few jobs ago... I'm sure someone is getting help from
Joe Hamelin, W7COM, Tulalip, WA, 360-474-7474
On Fri, Sep 17, 2010 at 6:00 PM, Tim Eberhard <xmin0s at gmail.com> wrote:
> To add on to that. Recently Wireshark Network Analysis was released. It's an
> excellent book covering wireshark and reading packet captures in general by
> Laura Chappell. I just finished reading it and I have to say it's an
> excellent book. Highly recommended.
> Between those two books I think you'll be very close to being a
> wireshark/packet capture guru.
> I hope this helps,
> -Tim Eberhard
> On Fri, Sep 17, 2010 at 7:33 PM, Joe Hamelin <joe at nethead.com> wrote:
>> In a situation like yours I found Internet Core Protocols: The
>> Definitive Guide by Eric Hall an easy to read guide to insuring that
>> what you are seeing via wireshark. I was able to find an issue with
>> the DF bit in a load balancer that was causing confounding headaches
>> in a network using wireshark and this book.
>> Walk it through the syn-ack dance and don't trust that the devices are
>> handling it correctly. Start at one end and work your way through and
>> insure to YOUR satisfaction that every device proscribes to the
>> protocol. Don't rush, don't jump to conclusions. Just follow the
>> packet. That's the best advice I can give you.
>> Joe Hamelin, W7COM, Tulalip, WA, 360-474-7474
>> On Fri, Sep 17, 2010 at 5:06 PM, Abel Alejandro
>> <aalejandro at worldnetpr.com> wrote:
>> > Greetings,
>> > This past week I have been trying to find the root cause of tcp
>> > performance problems of a few clients that are using a third party metro
>> > Ethernet for transport. RFC2544 tests (Layer 2) and iperf using UDP give
>> > good symmetric performance almost 100% the speed of the circuit. However
>> > all kind of TCP tests result in some kind of asymmetrical deficiency,
>> > either the upstream or downstream of the client is hugely different. The
>> > latency is not a huge factor since all the metro Ethernet connections
>> > have less than 2 ms.
>> > So the question basically if is there a good tutorial or white paper for
>> > troubleshooting tcp with emphasis of using tools like Wireshark to debug
>> > and track this kind of problems.
>> > Regards,
>> > Abel.
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