All Questions
50
questions
2
votes
0
answers
1k
views
Need help figuring out a random connection timeout issue on a server
I discovered this issue trying to loadtest a custom node.js websocket server, where some sockets are failing to connect (they hit the connection timeout). It does not appear to be related to the ...
- 121
1
vote
1
answer
1k
views
sudo netstat -antp not showing PID
i am testing stuff with sockets and i encountered that strange case :
i coded i very simple tcp server in c, i made it block after accept(), just to see what happen when accepting multiple connection ...
0
votes
1
answer
1k
views
How to make a port listener code in the server that hosts my website?
I have my website hosted in godaddy, and I want to test one of the Embedded Application's TCP data transfer using the IP and port number of my website, for this can I use any php script (something ...
0
votes
1
answer
883
views
Running Process Monitor causes application to work
This is a longshot, but perhaps someone with knowledge of the internal workings of Sysinternal's Process Monitor may have an idea.
Recently we've had a very murky problem at work. We have a software (...
- 115
1
vote
0
answers
211
views
Firewall : Is inbound required for getting response while Outbound rule already there?
I developed one MVC web application which have Web APIs and hosted in Amazon Instance and one windows application for calling those APIs for getting response from that server.
Both Web and Windows ...
0
votes
1
answer
2k
views
TCP socket buffer for every flow
Does the linux kernel create a buffer for every TCP connection, for example when we have 1000 tcp connections the kernel creates 1000 socket buffer and stores the packets of individual flow on its ...
- 11
1
vote
1
answer
6k
views
Socat not closing tcp connection
I use socat 1.7.3.1-r0 and run following command on an alpine 3.3 linux server:
socat -d -d -d PTY,link=/dev/ttyFOOBAR,echo=0,raw,unlink-close=0 TCP-LISTEN:7000,forever,reuseaddr
Socat will listen ...
- 145
2
votes
2
answers
5k
views
RST sequence number and window size
RFC793 states the following about RST processing:
In all states except SYN-SENT, all reset (RST) segments are validated
by checking their SEQ-fields. A reset is valid if its sequence number
is ...
- 21
3
votes
1
answer
1k
views
Is it necessary for an RST packet to have an acknowledgement number?
I am studying about TCP reset attack. I know that some RST packets have an acknowledgement number (with the ACK bit set), and some RST packets do not have an acknowledgement number (the ...
- 31
1
vote
1
answer
532
views
Acknowledgement number of an RST packet
This question states that the acknowledgement number of an RST packet should be 0, but I have found it to be other than 0 when I captured some HTTP packets using Wireshark.
So when does the ...
- 13
5
votes
1
answer
3k
views
How to list socket options of running processes?
Is there a convenient way (e.g. a readily-available command or a program that I can write using standard system calls) to list socket options (e.g. TCP_NODELAY) of an open TCP socket of some running ...
- 463
0
votes
1
answer
3k
views
TCP socket to serial port
Is is possibile to remotely access a serial port by tcp socket server? Exists this kind of software?
It is the opposit of this question:
Any free application to redirect serial communication to TCP/IP?...
- 2,311
0
votes
1
answer
91
views
TCP socket communication from client to server
I am trying to test the performance of a client/server application that uses TCP communication.
If I trigger multiple requests from the client, would it flow through the same connection/pipe to the ...
- 3
1
vote
0
answers
27
views
Route only on output chain?
I have two machines A and B. I want to send iperf traffic from A to B, but first have it route through a userspace program on A. I did this with a tunneling device: therefore, I used the command ip ...
- 111
5
votes
2
answers
6k
views
Data retransmission and WSAECONNABORTED (10053) socket error
Say I have two sockets that are connected to each other (Socket A and Socket B).
If the computer that have Socket B is unplugged from power, then if Socket A tries to send some data to Socket B, the ...
- 51