Linux operatsioonisüsteemis töötab võrguühendus

Sissejuhatus

Osutub, et tcp/ip network stack Linux, Windows, BSD jt implementatsioonid võimaldavad teatud tingimustel mitmel protsessil korraga sama pordi kasutada. Seda võimalust kehastab 'so_reuseport' socket option.

Tööpõhimõte

TODO

Väited

• haproxy - kasutatakse vaikimisi
• nginx - vaikimisi ei kasutata, aga soovitatakse kasutada jõudluse suurendamise eesmärgil
• zabbix-agent2 - ei ole võimalik kasutada

Kasutamine

Python skript

# cat socket-01-server.py
import socket
import os
import sys

PORT = 8083
# Fetch the Process ID so we can easily tell which instance answers the client
PID = os.getpid()

# 1. Create a standard TCP IPv4 Socket
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

# 2. THE MAGIC OPTIONS: Enable Reuse Address and Reuse Port
server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)

# 3. Bind and Listen (Standard blocking mode)
server_socket.bind(('0.0.0.0', PORT))
server_socket.listen(10)

print(f"[Worker PID: {PID}] Multi-core listening gate opened on port {PORT}...")

try:
    while True:
        # This call BLOCKS completely. The script sleeps right here in the kernel
        # until the Linux 4-tuple hash decides to route a client to THIS specific socket instance.
        client_socket, client_address = server_socket.accept()

        # Read the raw incoming HTTP request payload (up to 4KB)
        request = client_socket.recv(4096)

        if request:
            # Construct a basic HTTP response containing the answering process ID
            body = f"Hello from Worker Process ID: {PID}\n"
            response = (
                "HTTP/1.1 200 OK\r\n"
                "Content-Type: text/plain\r\n"
                f"Content-Length: {len(body)}\r\n"
                "Connection: close\r\n"
                "\r\n"
                f"{body}"
            ).encode('utf-8')

            # Fire the response back to the client
            client_socket.sendall(response)

        # Close the socket immediately to return the client line
        client_socket.close()

except KeyboardInterrupt:
    print(f"\n[Worker {PID}] Shutting down down gracefully.")
finally:
    server_socket.close()

Nginx

TODO

haproxy

TODO

Kasulikud lisamaterjalid

• TODO