Questions tagged [socket]
A socket is an abstract network construct with a sending and receiving side. In most modern operating systems (OS) there are device representations, and programming tools to address sockets.
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Socket Leak in Network-Intensive Application: Discrepancy in 'Closed' State Count
I'm experiencing a socket leak in a network-intensive application where the number of sockets in the 'closed' state reported by ss -s does not match the actual count from detailed commands. Here are ...
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How to allocate a tcp port orphaned by a non-existent process without restarting Windows [closed]
I'm encountering a persistent issue where a TCP port remains stuck in the LISTENING state, but the process that allocated it cannot be found. This happens even though the application that originally ...
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ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock'
Suddenly after restarting the machine, I have been facing this error can't connect to MySQL server and table plus is not able to connect with localhost 127.0.0.1.
The steps below worked for me, and ...
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What IP to assign my NIC in order to receive multicast traffic
I have a device (Blackmagic 2110 IP Converter 3x3G) connected to my PC that is sending me some ST-2110 video stream over 239.255.2.164.
I need to receive this data.
My NIC does not have any IP address ...
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What is the difference between "packet drops" from "ip -s link" and "socket drops" from "ss -tm"?
ss -tm shows detailed memory information about each TCP session. I found that some of the tcp sessions show sock_drop, here is one:
ESTAB ***** some irrelevant info here ****
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On linux, can I implement my own TCP stack while interoperating with other processes on same host?
I'm aware of two main ways to write and receive network packets from an existing network interface on linux. The first is with the classic sockets API, in which the linux kernel is responsible for ...
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Apache 2.4 config for fcgi with custom socket listening web app
I need a config for apache 2.4 which just connects to an open socket and talks fcgi over it.
I am writing my own fcgi-enabled web app. By now, it opens a listening socket and when a web server (nginx ...
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Why would a server not send ACK in response to PSH, ACK?
We have a client/server implementation, where the client continuously, periodically sends data at 800Hz over ethernet. The packets are small so we're significantly under the network bandwidth limit.
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Are raw sockets affected by iptables rules?
My understanding, from various sources (e.g. here and here) is that raw sockets are not affected by iptables rules. However in practice, I am seeing iptables prevent me from sending packets on a raw ...
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Linux Kernel keeps retransmitting data already ACKed by peer
I have the strange issue that a session without obvious cause hangs and timeouts. The session is a syslog stream with rather high volume, and traffic only flows from client to server. In capture files ...
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Can I make TCP_NODELAY a default setting for all connections on a GNU/Linux system?
This article:
It’s always TCP_NODELAY. Every damn time.
suggests, as a bottom line, to set TCP_NODELAY by default, always. Can I do that on a (recent) GNU/Linux system...
As root, for all sockets ...
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Cannot connect to a port on Ubuntu 22.04 x64
I have MySQL running on port 1835, as proven by running the command:
lsof -i:1835
The following was run to open the port on the firewall:
ufw allow 1835/tcp
ufw enable
ufw reload
But the port cannot ...
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Kernel TLS Socket Redirect
Suppose both the client as well as the server are on the same machine and they want to do mTLS. They both choose to offload the TLS to Kernel (kTLS). Now when the key exchange happens, given the ...
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What does it mean when netstat outputs a dash in pid / program name column?
Here is some lightly modified output from netstat (I removed the addresses and names)
a@xxxxx:/app# netstat -p
Active Internet connections (w/o servers)
Proto Recv-Q Send-Q Local Address ...
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How does real server, direct return server (DRS), reply to client if a load balancer (LB) uses port address translation (PAT)?
Direct Return Server overview:
The DRS allows real servers to directly reply to a client without going through load balancer (LB). The LB ip (VIP) is configured as a loopback (localhost) ip for the ...
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