MonPi

-an admin's favorite portable tool

by Ernest Stratoberdha

High-level

• Get resource usage:
  • CPU
  • Memory
  • Bandwidth
• Visualize them using graphs

Pi setup

• Raspbian OS
• Static IP address
• VNC server
• Flask framework

Pi setup

• Python packages
  • psutil
  • matplotlib
  • numpy
• Network tools
  • tshark

Remote management

Home

• SSH tunneling for VNC
• Configurations on the network
  • Port-forwarding
  • OpenVPN on the router

Remote management

Networking Lab

• Port mirroring for Cisco switch 2960
• Public-facing
• Fail2ban

Home environment

Lab environment

2960 Cisco switch config

monitor session 1 source interface Gi0/24
monitor session 1 destination interface Gi0/12 ingress untagged vlan 99

Graphing

• tshark to capture packets
• psutils lib to get system usage
• flask to run web app
• matplotlib to build graphs

Graphing

Code

import os
import subprocess
import sys
import threading
from flask import Flask
from flask import render_template, abort
app = Flask(__name__)
app.debug = True

# function to call netcap.py script to capture traffic
def run_script():
    theproc = subprocess.Popen(['python', 'netcap.py'])
    theproc.communicate()


@app.route('/')
def index():
    return render_template('index.html')
 
@app.route('/basics')
def basics():
    return render_template('basics.html')

@app.route('/about')
def about():
    return render_template('about.html')
  
@app.route('/generate')
def generate():
    threading.Thread(target=lambda: run_script()).start()
    return render_template('processing.html')

@app.route('/is_done')
def is_done():
     hfile = "templates\itworked.html"
     if os.path.isfile(hfile):
         return render_template('itworked.html')
     else:
         abort(404)

if __name__ == "__main__":
    app.run()

app.py

Code

import subprocess
import sys
import os.path
import psutil

print "Monitoring broadcast packets on the network..."

# loop range set arbitrarily for testing
for x in range(0, 10): 

    subprocess.call(['sudo tshark -i eth0 -a duration:2 -w /root/capfile'], shell=True)
    # moving file to different location to avoid root permission problem
    subprocess.call(['sudo mv /root/capfile /home/nestig/monpi/capfile'], shell=True)
    # next 3 lines are calls to process output formatting of packets captured
    pcap = subprocess.Popen(["sudo", "capinfos", "-yu", "/home/nestig/monpi/capfile"], stdout=subprocess.PIPE)
    lrow = subprocess.Popen(["awk",  "NR==3"], stdin=pcap.stdout, stdout=subprocess.PIPE)
    dbrate = subprocess.Popen (["cut",  "-c22-25"], stdin=lrow.stdout, stdout=subprocess.PIPE)
    pcap.stdout.close() # close output stream
    lrow.stdout.close()  # close output stream
    stdout, stderr = dbrate.communicate() # connects PIPE
    sys.stdout.write(stdout) # no newline bullshit
    infile = "/home/nestig/monpi/logs/network.txt" # path to the input file to be modified
    openfile = open(infile, 'a')
    space = " " 
    y = x * 5	# holds approximate intervals
    
    # write the formatted data to file
    openfile.write(str(y))
    openfile.write(space)    
    openfile.write(stdout)
    openfile.close()	

# call psutils.py to get memory and cpu stats
subprocess.call(['python /home/nestig/monpi/psutils.py'], shell=True)

netcap.py

Code

psutils.py

# import the libraries needed
import sys
import subprocess
import psutil as ps


# demonstrate psutil for memory and cpu usages

print "Collecting info on RAM and CPU: "

for x in range(0, 10):
    cpu = ps.cpu_percent(interval=2)
    mem = ps.virtual_memory()
    m = mem.used >> 20
     
    mfile = "/home/nestig/monpi/logs/memory.txt"
    cfile = "/home/nestig/monpi/logs/cpu.txt"
    space = " "
    newline = '\n'
    y  = x * 5 # arbitrarily set loop variable to get samples
    
    # open memory log file
    openfile = open(mfile, 'a')      
    openfile.write(str(y))
    openfile.write(space)
    openfile.write(str(m))
    openfile.write('\n')
    openfile.close()
    
    # open cpu log file
    openfile = open(cfile, 'a')
    openfile.write(str(y))
    openfile.write(space)
    openfile.write(str(cpu))
    openfile.write('\n')
    openfile.close()
    
   
     

# call filedata_graph.py to plot
subprocess.call(['python /home/nestig/monpi/filedata_graph.py'], shell=True)

subprocess.call(['cat /dev/null > /home/nestig/monpi/logs/network.txt'], shell=True)
subprocess.call(['cat /dev/null > /home/nestig/monpi/logs/memory.txt'], shell=True)
subprocess.call(['cat /dev/null > /home/nestig/monpi/logs/cpu.txt'], shell=True)

Future

Add storage monitoring.

Add report features.

Improve front-end of MonPi.

Website

MonPi.net is alive!

Questions

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