Hello,

if everything is working fine with the audio, then just ignore the tcpdump warning, since it may capture the packets before the checksum was actually computed in the system. With some network cards you'd have to disable hardware checksum to get rid of those warnings. again, afaik, it is harmless if everything works.

I recommend using version 3.1 for running kamailio in amazon instances, it does it far more better than older versions. I was even running kamailio and asterisk on same ec2 instance, but with some tricks to record routing. For rtp relaying I was using rtpproxy.

Cheers, Daniel

On 1/24/11 12:42 AM, Chandrakant Solanki wrote:

Hi

I have installed Kamailio with MediaProxy and asterisk on Amazon Server.. While kamailio/MediaProxy and Asterisk both running on different amazon's instance.

Kamailio : 1.5.0-notls MediaProxy : 2.3.8

Asterisk : 1.6.2.6

Firewall port is opened for mediaproxy from 10000-20000 (UDP), 5060 (UDP) etc on both amazon machine..

while I tried to play an audio... it plays sound file but unable to found audio on device.

when I put tcpdump on asterisk machine it gives following error...

# tcpdump -i eth0 udp portrange 10000-20000 -w test1.pcap

01:39:52.850279 IP (tos 0xb8, ttl 64, id 59, offset 0, flags [DF], proto: UDP (17), length: 60) ip-W.X.Y.Z.compute.internal.15246 > xyz.com.10010: [bad udp cksum 3cfd!] UDP, length 32 01:39:52.870279 IP (tos 0xb8, ttl 64, id 60, offset 0, flags [DF], proto: UDP (17), length: 60) ip-W.X.Y.Z.compute.internal.15246 > xyz.com.10010: [bad udp cksum 97fe!] UDP, length 32 01:39:52.890281 IP (tos 0xb8, ttl 64, id 61, offset 0, flags [DF], proto: UDP (17), length: 60) ip-W.X.Y.Z.compute.internal.15246 > xyz.com.10010: [bad udp cksum 75c0!] UDP, length 32

Any Idea..!!

-- Regards,

Chandrakant Solanki

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