How to make TURN Server for high availability?

If you want to keep your WebRTC video streaming services online without any downtime, you must pay attention to the availability of TURN Server. Because TURN Server plays an important to help two parties to connect to each other with Video or Audio streaming in different NAT networks.

The following instructions show how to automatically monitor your TURM server and restart it during the downtime.


1. Install pexpect lib in Python 

sudo pip install pexpect --upgrade



2. Edit MonitorStun.py 
- Telnet your TURN Serer 
- If it is down, ssh to your server and restart it  

#!/usr/bin/env python

import socket

import subprocess

import sys

from datetime import datetime

from pexpect import pxssh

# SSH TO TURN SERVER and restart it

def connect_turn_server():

  s = pxssh.pxssh()

  if not s.login ('TURN Server IP', 'SERVER PORT', 'ACCOUNT', 'PASSWORD'):

    print "SSH session failed on login."

    print str(s)

  else:

    print "SSH session login TURN successful"

    s.sendline ('sudo turnserver -c /usr/local/etc/turnserver.conf --daemo')

    s.prompt()         # match the prompt

    print s.before     # print everything before the prompt.

    s.logout()

# Telnet TURN Server to check it is alive or not on PORT 3478 or 3479

# Clear the screen

subprocess.call('clear', shell=True)

# Ask for input

remoteServer    = 'SERVER IP'

remoteServerIP  = socket.gethostbyname(remoteServer)

# Print a nice banner with information on which host we are about to scan

print "-" * 60

print "Please wait, scanning remote host", remoteServerIP

print "-" * 60

# Check what time the scan started

t1 = datetime.now()

# Using the range function to specify ports (here it will scans all ports between 1 and 1024)

# We also put in some error handling for catching errors

try:

    for port in range(3478,3479):

        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

        result = sock.connect_ex((remoteServerIP, port))

        if result == 0:

            print "Port {}:      Open".format(port)

        else:

             print "TURN Server is down"

             connect_turn_server()

             print "restart TURN Server OK"

        sock.close()

except KeyboardInterrupt:

 print "You pressed Ctrl+C"

    sys.exit()

except socket.error:

    print "Couldn't connect to server"

    sys.exit()

                                        

3. Add MonitorStun.py to con job to check TURN Server in every 1 min.

*/1 * * * * /your_path/monitorStun.py

Of course, you can apply this technique to monitor any services such as SIP Proxy with port 5060, Apache with port 80, or Tomcat with port 8080.