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my server is connected to several clients. there is an expected packet I want to get from one of the clients to my application on the server, but I don't get it. when I use wireshark, I see that this packet came from the client but there no ACK on this packet from the server. then, the client retransmit this packet again and again, but there is no ACK. if the send window of the server is full - is there any indication on this in wireshark? or - what can be the root cause for the above issue?


asked 08 Feb '12, 02:35

gln's gravatar image

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edited 08 Feb '12, 02:36

Does the handshake to the server work properly ? Is the packet from the client, that does not arrive at the server a fullsized segment ?

(08 Feb '12, 04:32) Landi

yes, the handshake works properly. I don't understand the second question - can you please add details how can I see it?

(08 Feb '12, 11:50) gln

how big are those packets, which the server does not ACK and is there any packet which is acked at all except during 3-way-handshake?

(09 Feb '12, 01:12) Landi

those packet are 20 size.. there is an acks in this connection for several minutes, but then there is no ack somehow

(09 Feb '12, 01:56) gln

sounds to me like a device in between that does not forward packets to the server after a certain event (firewall?). If you see the packets outgoing from the client but not incoming at the server I'd look at devices in the middle capable of traffic filtering

(09 Feb '12, 04:20) Landi

Run a capture at the server side to ensure that the packets are arriving.

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answered 10 Feb '12, 13:34

dixglata's gravatar image

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question asked: 08 Feb '12, 02:35

question was seen: 5,864 times

last updated: 10 Feb '12, 13:34

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