[Planetlab-users] tcpdump and capturing incoming packets

[Sapan Bhatia]

Hi Greg,

Ok, that's one problem down in that case. The tweak I made was to
allow slices to receive packets over TIME_WAIT connections, which they
were previously not allowed to do.

Could you try your code on this node: echo.cs.princeton.edu. It's an
alpha node that I'll be able to update with my change. If it doesn't
work for you when you test it now, but works after the change, then we
can mark the change for deployment.

Thanks very much!
Sapan

On Mon, Jul 14, 2008 at 6:50 PM, Greg Banks <nomed at cs.ucsb.edu> wrote:
>
> hi sapan,
>
> i just tried out my test case on delta and planetlab-7 and they both seem to
> function fine. all i did was run:
>
> nc planetlab2.cse.nd.edu 4545
>
> submitting a GET request to the proxy there:
>
> GET / HTTP/1.1
> host: www.cs.ucsb.edu
>
> tcpdump reported all the packets (except for the SYN/ACK, which i do need
> access to, but i guess this is provided through vsys somehow?)...
>
> i also tried it again using the host that i used originally
> (planetlab01.dis.unina.it) with no success...
>
> cheers,
> greg
>
> On Jul 14, 2008, at 2:52 PM, Sapan Bhatia wrote:
>
>> Hi Greg and Zhichun,
>>
>> Could you try your code on the following boxes:
>> planetlab-7.cs.princeton.edu and delta.cs.princeton.edu?
>>
>> If it doesn't work, then it would be nice if you could come up with a
>> test case that I could execute to observe the problem.
>>
>> Thanks,
>> Sapan
>>
>> On Wed, Jul 9, 2008 at 8:08 PM, Greg Banks <nomed at cs.ucsb.edu> wrote:
>>>
>>> hi all,
>>>
>>> i am new to planet lab and am having some problems with tcpdump and
>>> capturing http sessions that are originating from my slice/node.
>>> basically,
>>> i see all outgoing packets, including those with an HTTP payload, but
>>> only
>>> incoming ACKs with no HTTP payload (not even SYN/ACK packets). here is
>>> some
>>> sample output when trying to capture http traffic to a proxy running on
>>> port
>>> 4545:
>>>
>>> 01:04:33.187359 IP planetlab01.dis.unina.it.43387 >
>>> planetlab01.mpi-sws.mpg.de.worldscores: S 1248952370:1248952370(0) win
>>> 5840
>>> <mss 1460,sackOK,timestamp 1116447448 0>
>>> E..8". at .@............{..Jq.2........K..........
>>> B.......
>>> 01:04:33.219712 IP planetlab01.dis.unina.it.43387 >
>>> planetlab01.mpi-sws.mpg.de.worldscores: . ack 55681466 win 5840
>>> <nop,nop,timestamp 1116447481 229909180>
>>> E..4". at .@............{..Jq.3.Q.......(.....
>>> ."..
>>> 01:04:39.933180 IP planetlab01.dis.unina.it.43387 >
>>> planetlab01.mpi-sws.mpg.de.worldscores: P 0:15(15) ack 1 win 5840
>>> <nop,nop,timestamp 1116454194 229909180>
>>> E..C". at .@............{..Jq.3.Q.......K.....
>>> .".GET / HTTP/1.1
>>>
>>> 01:04:39.966642 IP planetlab01.mpi-sws.mpg.de.worldscores >
>>> planetlab01.dis.unina.it.43387: . ack 15 win 5792 <nop,nop,timestamp
>>> 229915928 1116454194>
>>> E..4.f at .1.7{...........{.Q..Jq.B....[......
>>> .=.B..2
>>> 01:04:45.387559 IP planetlab01.dis.unina.it.43387 >
>>> planetlab01.mpi-sws.mpg.de.worldscores: P 15:37(22) ack 1 win 5840
>>> <nop,nop,timestamp 1116459649 229915928>
>>> E..J". at .@............{..Jq.B.Q.......t.....
>>> .=.host: www.cs.ucsb.edu
>>>
>>> 01:04:45.419964 IP planetlab01.mpi-sws.mpg.de.worldscores >
>>> planetlab01.dis.unina.it.43387: . ack 37 win 5792 <nop,nop,timestamp
>>> 229921384 1116459649>
>>> E..4.g at .1.7z...........{.Q..Jq.X....0......
>>> .RhB...
>>> 01:04:45.628316 IP planetlab01.dis.unina.it.43387 >
>>> planetlab01.mpi-sws.mpg.de.worldscores: P 37:38(1) ack 1 win 5840
>>> <nop,nop,timestamp 1116459889 229921384>
>>> E..5". at .@............{..Jq.X.Q......%......
>>> .Rhq
>>>
>>> 01:04:45.661794 IP planetlab01.mpi-sws.mpg.de.worldscores >
>>> planetlab01.dis.unina.it.43387: . ack 38 win 5792 <nop,nop,timestamp
>>> 229921625 1116459889>
>>> E..4.h at .1.7y...........{.Q..Jq.Y..../......
>>> .SYB..q
>>> 01:04:46.307563 IP planetlab01.dis.unina.it.43387 >
>>> planetlab01.mpi-sws.mpg.de.worldscores: . ack 1449 win 8688
>>> <nop,nop,timestamp 1116460569 229922271>
>>> E..4". at .@............{..Jq.Y.Q.b..!........
>>> .U..
>>> 01:04:46.307768 IP planetlab01.dis.unina.it.43387 >
>>> planetlab01.mpi-sws.mpg.de.worldscores: . ack 2897 win 11584
>>> <nop,nop,timestamp 1116460569 229922271>
>>> E..4". at .@............{..Jq.Y.Q.
>>> ..- at .......
>>> .U..
>>> 01:04:46.307790 IP planetlab01.dis.unina.it.43387 >
>>> planetlab01.mpi-sws.mpg.de.worldscores: . ack 4127 win 14480
>>> <nop,nop,timestamp 1116460569 229922271>
>>> E..4". at .@............{..Jq.Y.Q....8........
>>> .U..
>>> 01:04:46.483128 IP planetlab01.dis.unina.it.43387 >
>>> planetlab01.mpi-sws.mpg.de.worldscores: . ack 5575 win 17376
>>> <nop,nop,timestamp 1116460744 229922446>
>>> E..4". at .@............{..Jq.Y.Q....C........
>>> .V..
>>> 01:04:46.483155 IP planetlab01.dis.unina.it.43387 >
>>> planetlab01.mpi-sws.mpg.de.worldscores: . ack 7023 win 20272
>>> <nop,nop,timestamp 1116460744 229922446>
>>> E..4". at .@............{..Jq.Y.Q.(..O0.......
>>> .V..
>>> 01:04:46.484308 IP planetlab01.dis.unina.it.43387 >
>>> planetlab01.mpi-sws.mpg.de.worldscores: . ack 8231 win 23168
>>> <nop,nop,timestamp 1116460745 229922446>
>>> E..4". at .@............{..Jq.Y.Q....Z........
>>> .V..
>>> 01:04:46.484331 IP planetlab01.dis.unina.it.43387 >
>>> planetlab01.mpi-sws.mpg.de.worldscores: . ack 9679 win 26064
>>> <nop,nop,timestamp 1116460745 229922447>
>>> E..4". at .@............{..Jq.Y.Q....e........
>>> .V..
>>>
>>> should this be the case? am i doing something wrong? any suggestions
>>> would
>>> be much appreciated. thanks.
>>>
>>> cheers,
>>> greg
>>>
>>> _______________________________________________
>>> Users mailing list: Users at lists.planet-lab.org
>>> https://lists.planet-lab.org/mailman/listinfo/users
>>>
>
>