Network Port Scan

[XionTech]

I'm using my Pi as a simple video stream viewer with omxplayer loading the static IP of my rtsp stream. However, I use this on different networks (including the stream server) so the server and my Pi change IPs. I can't have static since the IP pool is sometimes 10.xxx.xxx.xxx or sometimes 192.xxx.xxx.xxx etc. And I don't always have access to the router. (it's a video relay used in public venues).

Is there a brilliant script that can scan the currently connected network (looking for an rtsp port or a particular file that would be hosted on my server) and return the IP of the server?

[AikonCWD]

Yes, I recommend you to use nmap. You can scan the entire network in seconds, return the MAC address of each device and get the associated IP. If you provide more information, I can try to code a working script for you.

[XionTech]

The server is an axis q7401. So I pretty much run a quiet boot on my pi to a bash script which executes omxplayer -*myparams rtsp://ipaddress/axis-media/media.amp

Thank you so much for the assist...

[DougieLawson]

Code: Select all

#!/usr/bin/python
from pyroute2 import IPRoute
import socket
ip = IPRoute()
for x in ip.get_addr(label='eth0',family=socket.AF_INET):
  ipa =x.get_attr('IFA_ADDRESS')+"/"+str(x['prefixlen'])

print "My IP:", ipa
import subprocess
process = subprocess.Popen(['sudo','nmap','-oX', '/tmp/nmap.xml','-sn',ipa],
stdout=subprocess.PIPE)
process.wait()

import xml.etree.ElementTree as ET
tree = ET.parse('/tmp/nmap.xml')
for node in tree.iter('address'):
  try:
    if node.attrib['addrtype'] == "ipv4":
      ip = node.attrib['addr']
  except:
    pass
  try:
    if node.attrib['vendor'] == "Raspberry Pi Foundation":
      print "Other Raspberry IP:", ip
  except:
    pass

[XionTech]

Can I call a python script from a bash and return an argument (ip) or should I switch to using a python script to retrieve and call the omxplayer from that?

[AikonCWD]

First install nmap on your Pi

Code: Select all

sudo apt-get install nmap

Than run this command:

Code: Select all

sudo nmap -sP 192.168.0.0/24 | awk '/Nmap scan report for/{printf $5;}/MAC Address:/{print " "$3;}' | grep 7C:05:07:21:35:44 | awk '{print $1}'

Where 192.168.0.0/24 is your network and 7C:05:07:21:35:44 is the MAC address of the device you want to know the IP.

[mfa298]

... And I don't always have access to the router. (it's a video relay used in public venues).

Is there a brilliant script that can scan the currently connected network (looking for an rtsp port or a particular file that would be hosted on my server) and return the IP of the server?

Note that scanning the network like that might be seen as a breach of the TOS for connecting to the network. Whist many places may not care its possible some venues could have something in place that detects such network scans. </pedantMode>

The obvious alternatives I can think of would be to have the devices send an email with it's internal (and external IP). Or have a small screen that could provide diagnostic information (IP address, streaming state etc).