Questions tagged [tcp]
TCP stands for Transmission Control Protocol and is one of the core protocols of the Internet Protocol Suite. TCP complements the Internet Protocol (IP), and therefore the entire suite is commonly referred to as TCP/IP.
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High TCP retransmissions from RHEL 8.6 client (BBR) to RHEL 7.9 server (Cubic) during iperf3 test [closed]
We're testing TCP performance between a client and server using iperf3 in a controlled environment.
Client: RHEL 8.6 with BBR congestion control enabled
Server: RHEL 7.9 using default Cubic congestion ...
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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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When one node connects to more than 1000 nodes using an envoy proxy, there are some connection failures with `URX` status code. What can fix this?
I am connecting two services behind envoy proxy and each node makes 6 TCP connections to another. The nodes are designed to connect from one->many.
When one node tries to connect to more than 1000 ...
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How can I limit the number of accepted sessions on a specific port in Windows server?
I have a Windows service that is limited in the number of threads it can handle at a given time, say 10. But Windows will accept many more than that simultaneous TCP connections on the listening port (...
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Unusual TCP connection issue and Windows Server 2022 strange behavior
Last night I had another unsuccessful attempt to migrate one of the machines to a newer version of Windows Server. The entire system is composed from several virtual machines running Windows Server ...
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Nginx TCP steam $ssl_preread_server_name randomly fail to extract host
I'm struggling with a puzzling behavior. I have a TCP streamer in front of:
and NGINX site listening to 127.0.0.1:444
a traefik ingress endpoint (:8443) exposing all of my services
and a k8s ...
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Persistent ephemeral port reuse and CLOSE_WAIT states after cold reboot
I'm running into a persistent and puzzling issue involving two Linux and one Windows guest VMs hosted on a third-party VMware ESXi server, and I'm hoping someone here can offer insight or share a ...
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From client POV, ICMP (ping) works, but any TCP connection does not
Here's a strange situation on a Windows Server 2016 Standard:
(All within our AD domain)
Any ping request works just fine but whenever a TCP connection is tried to be established, this does not work.
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Windows Server with 10Gbit NIC - Severe Performance Issues over Certain Routes
we recently upgraded our Windows server (hosted by Hetzner) to a 10Gbit/s connection. The server does reach the full 10Gbit/s capacity, and our customers are not reporting any issues. However, we're ...
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redhat + how to revert TCP BBR congestion changes
We have configured the BBR settings on all our RHEL 8.6 machines as follows: (according to Red Hat's documentation [https://access.redhat.com/solutions/3713681]). The goal is to assess whether the BBR ...
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How can 10G link be slower to WAN than 1G link, on the same machine?
I'm using the following command to test network speed to my.remote.server, from my workstation:
dd if=/dev/random | pv | ssh my.remote.server "dd of=/dev/null"
When I set en0 to 10Gb, ...
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Use LLD in zabbix to discover open TCP ports
We're using Zabbix 6.0 and want to monitor application ports on around 40 Debian 11 servers. There runs multiple times the same application on each server, so there are two to 11 ports to monitor.
I ...
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Network stops working in one direction for 40s, then fixes itself
I'm a Java developer.
Something strange happened recently and I am a bit befuddled and would like to have a list of hypothesis to start asking the right questions.
The TCP connection between two Java ...
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How to Forward TCP Packets to Multiple Destinations Using nftables?
I am looking for a solution where TCP packets need to be forwarded or broadcasted to multiple destinations. Using nftables, I managed to forward packets to another machine with the following rule:
nft ...
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Random Linux->Windows retransmissions with delays/timeouts
We have been notified about random application slowness and random HTTP 503 errors coming from the reverse proxy machine (Debian/Apache).
HTTP requests coming from Debian/Apache machine are received ...
