TAS not sending a SYN-ACK back to client

Question

TAS not sending a SYN-ACK back to client

ash995 opened this issue 4 years ago · 4 comments

We have a client connecting to a TAS server. The application send a bunch of SYN packets to the TAS server, but TAS never responds with a SYN-ACK, and hence the connection never succeeds.

Answer 1 · 2021-02-02T08:38:09.000Z

Again, I will need a bit more detail to help at all here. Including:

are both sides running TAS or only the server?
what applications are you running? one of the TAS benchmarks or something else?

Connection setup is done in the slowpath in TAS. I would start debugging by enabling the debug prints here: https://github.com/tcp-acceleration-service/tas/blob/master/tas/slow/tcp.c#L58-L59

Answer 2 · 2021-02-08T14:31:46.000Z

Only the server runs on TAS and the client run on top of Linux.

We are running a custom application on top of TAS. The benchmarking (echoserver_linux) application runs fine.

Ok, thanks. I'll enable the debugging prints and get back with more info.

Answer 3 · 2021-02-12T06:08:32.000Z

This was a mistake on our end. We were creating a listening socket on one thread and waiting for connections on that listening socket on another thread, and I guess TAS was kicking the first thread with new connections (the thread which is not waiting for connections), and hence a SYN-ACK packet was never returned.

Answer 4 · 2024-05-16T05:31:07.000Z

Hello, I also encountered the same problem as you. Could you please let me know how you solved it?

This was a mistake on our end. We were creating a listening socket on one thread and waiting for connections on that listening socket on another thread, and I guess TAS was kicking the first thread with new connections (the thread which is not waiting for connections), and hence a SYN-ACK packet was never returned.