Server-side implementation to reproduce "Connection reset by peer"

tcp_close_serv.py

#!/usr/bin/env python3
import logging
import socket
import struct
import time

logger = logging.getLogger(__name__)
logging.basicConfig(level=logging.INFO, format="[%(levelname)s] %(message)s")
s = socket.socket(socket.AF_INET6)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

# if we want to inherit this option:
#s.setsockopt(socket.SOL_SOCKET, socket.SO_LINGER, struct.pack('ii', 1, 0))
s.bind(('', 9999))
s.listen()
logger.info("listen")

while True:
    con, addr = s.accept()
    logger.info("accept from %s", addr)
    con.setsockopt(socket.SOL_SOCKET, socket.SO_LINGER, struct.pack('ii', 1, 0))
    time.sleep(1)
    con.close()
    logger.info("close connection")