Tiny Python Syslog Server

pysyslog.py

#!/usr/bin/env python

## Tiny Syslog Server in Python.
##
## This is a tiny syslog server that is able to receive UDP based syslog
## entries on a specified port and save them to a file.
## That's it... it does nothing else...
## There are a few configuration parameters.

LOG_FILE = 'youlogfile.log'
HOST, PORT = "0.0.0.0", 514

#
# NO USER SERVICEABLE PARTS BELOW HERE...
#

import logging
import SocketServer

logging.basicConfig(level=logging.INFO, format='%(message)s', datefmt='', filename=LOG_FILE, filemode='a')

class SyslogUDPHandler(SocketServer.BaseRequestHandler):

	def handle(self):
		data = bytes.decode(self.request[0].strip())
		socket = self.request[1]
		print( "%s : " % self.client_address[0], str(data))
		logging.info(str(data))

if __name__ == "__main__":
	try:
		server = SocketServer.UDPServer((HOST,PORT), SyslogUDPHandler)
		server.serve_forever(poll_interval=0.5)
	except (IOError, SystemExit):
		raise
	except KeyboardInterrupt:
		print ("Crtl+C Pressed. Shutting down.")

Can you explain why would I use this instead of the real syslog facility?

You can add utf-8 encoding to improve the server:

def handle(self):
    data = bytes.decode(self.request[0].strip(), encoding="utf-8")
    socket = self.request[1]
    print( "%s : " % self.client_address[0], str(data.encode("utf-8")))
    logging.info(str(data.encode("utf-8")))

It worked very well when I needed a syslog server for some tests. Thanks for sharing.

Cute. If you are in python3, simply change SocketServer to socketserver. Official reference here

I developed a Python 3 implementation of a simple UDP syslog server which inserts the recieved messages into a MariaDB or MySQL database. https://github.com/choeffer/py3syslog
Your piece of code was helping me a lot to get started so I share mine also.

Thx, using it for routers monitoring :p

Nice thanks, will use it to trigger another script after syslog message is sent through EEM script.

I am just beginner in codding and my apoligise if I miss out the point but can someone explain me how to receive logs from regarding system? Don't you need to add this code in somewhere?

logging.getLogger()

Thanks for this useful script to help to receive the syslog and send to Apache Kafka.

@maxenc7, seems like the contention is in the implementation of the logging.info() call itself. Nothing I can do there. That said, 1M/s seems a little bit too much for this tiny logger to handle. In fact, seems a lot for anything to handle in that amount of time. You are probably gonna have to use something to load balance this (haproxy or nginx) and then use several backends. This is completely outside the scope of this gist.

data is already the buffer. No need to double-buffer it or you will incur in extra latency. In regards to writing directly into the file, that can surely be done. You might have noticed that this code is 8+ years old, and I havent touched it (or even used it) in a long time. you are more than welcome to suggest a fix ;-)

how many syslogs can it process ? is there a limit

Thanks a lot i used your script!

Hi, I am using this code a lot. But this server is not able to get logs when sending from a python SyslogHandler as shown in the code below

# sending logs to server
import logging
from logging.handlers import SysLogHandler
import time

logger = logging.getLogger()
logger.setLevel(logging.INFO)
logger.addHandler(SysLogHandler(address=('localhost', 514)))

for i in range(20):
    logger.info("Hello World!!!")
    time.sleep(1)

Hi, I am using this code a lot. But this server is not able to get logs when sending from a python SyslogHandler as shown in the code below

# sending logs to server
import logging
from logging.handlers import SysLogHandler
import time

logger = logging.getLogger()
logger.setLevel(logging.INFO)
logger.addHandler(SysLogHandler(address=('localhost', 514)))

for i in range(20):
    logger.info("Hello World!!!")
    time.sleep(1)

Hi, I resolved this issue.
It is working if send logs to "127.0.0.1" instead if "localhost"
So writing logger.addHandler(SysLogHandler(address=('localhost', 514))) solved the issue and logs are sent to python syslog listener

It is working if send logs to "127.0.0.1" instead if "localhost"

The hostname localhost typically resolves to the 127.0.0.1 loopback address, and is reserved for this purpose in RFC 6761 section 6.3. However, not every platform defines the mapping.

It is working if send logs to "127.0.0.1" instead if "localhost"

The hostname localhost typically resolves to the 127.0.0.1 loopback address, and is reserved for this purpose in RFC 6761 section 6.3. However, not every platform defines the mapping.

👍