[Planetlab-users] TCPDUMP response side traffic lost

[Hecker W]

I need to issue HTTP requests from Planetlab nodes and
to dump the whole TCP connection traces. I found it worked
on the FC4 version. But for the FC8 version, after the initial
SYN packet sent out, I cannot capture the server response
traffic until 0.6 second later. All the packets responded from
web servers are lost within this 0.6 second time window. After that
I can get all the traffic from both side.  I tried the big web objects to
make
sure its downloading time is longer than 1 seconds, and find this problem is
persistent.

I am not sure whether it is due to the new version of Planetlab needs
0.6 seconds to recognize that the new connection is issued so that it begin
to
allow TCPDUMP to see the packets?

I guess it is not expected behavior, doesn't it? I did not use any raw
socket API.

The problem is similar to the problem mentioned by Greg in the previous
post.

If anyone needs the pcap trace to see the problem please reply the post. I
will make it available online.

Thanks
-Zhichun
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