All Questions
24
questions
0
votes
1
answer
245
views
How is an IP address assigned to a process in TCP?
When TCP connection is established between two sockets, suppose that there are multiple NICs in the computer, so which IP address will the socket bind [ or - which IP address will be passes into bind()...
- 11
-2
votes
1
answer
239
views
How to investigate why a computer stops a TCP connection?
I've just written this question on another StackExchange site, but I was advised to ask the same question here.
I would like to broaden the question: how can I know why a host closes a TCP socket ...
- 2,283
2
votes
0
answers
2k
views
WebSocket connections originating from local network all use same client-side port (instead of ephemeral) when connecting to local webserver - Why?
I set up a webserver on a virtual machine on my home desktop. I have my router forward several ports (80, 443, etc) to my desktop, when then forwards them via NAT to the virtual machine (see diagram ...
- 21
0
votes
1
answer
4k
views
Increase buffer size for a specific socket on Linux
I am using CentOS7 and I have to increase the send buffer size (SO_SNDBUF) on a socket listening on a specific port. The application that has the port opened does not natively support this.
Few things ...
1
vote
0
answers
45
views
understand ss -to4 output for a jdbc connection
My application connects to a database over JDBC, and performs a lot of sequential inserts. There is only 1 JDBC connection opened by the application. As the performance is not as expected, I started ...
- 11
4
votes
1
answer
5k
views
How can I know what is preventing my socket to bind to localhost:50060-50959
I am using this Python code to listen to a port on my Windows 10 system:
import socket
for port in (50059, 50060, 50959, 50960):
try:
print(socket.socket(socket.AF_INET, socket.SOCK_STREAM)....
- 1,728
2
votes
0
answers
307
views
How can I use the "location of socket in memory" field in /proc/net/tcp
I'm working on a proxy for linux(C++) that, amongst other functions, keeps track of tcp connections and associates them with the process's pid. To do that, I get the inode in /proc/net/tcp and then ...
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 ...
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
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
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