How to run a command to use data from a txt file to execute them one by one smartly

Question

I will explain it precisely!

1. So, i have 8 friends using same internet connection which i do and mostly we play games online.
2. Connection is such that when you switch on your connection it displays a login page of ISP which allow you go online only after you login.

3. We have each others mac address.Now to check either any of my friend is online or not i execute the following command:

   sudo ifconfig en0 ether xx:xx:xx:xx:xx:xx; sudo ifconfig en0 down; sudo ifconfig en0 ether up; sleep 6; ping -c 3 www.google.co.in;

4. Where xx:xx:xx:xx:xx:xx=MAC ADDRESS, en0=ethernet

5. I use sleep as it takes about 6 seconds to connect router

6. So ping shows me result whether they are online or not

7. Now i have 8 such mac addresses in a txt file organised as each in one line.

Q1) Can i use only one command such that it takes each mac address from text file one by one and uses it in above command and ends as my txt ends?

Q2) Is there any Alternative command for above purpose as the above command is organised by myself to work properly as per my use?

I work with Mac OS

Answer 1

Here's the final quote

#!/bin/bash
while read m; do
   echo Checking MAC address: $m
   sudo ifconfig en0 ether $m
   sudo ifconfig en0 down
   sudo ifconfig en0 up
   sleep 5
   i=1
  while [ $i -eq 1 ]
    do
      ping -c 3 www.google.co.in > /dev/null
      e=$?
         if [ $e -eq 0 ]
          then
            echo ONLINE
            i=0
            echo $m >> ONLINE.txt
         elif [ $e -eq 2 ]
          then
           echo OFFLINE
           i=0
           echo $m >> OFFLINE.txt
         else
           echo Waiting To be Connected
           i=1
           sleep 4
         fi
    done
done < macs.txt
echo HI, These macs are ONLINE
cat ONLINE.txt
echo Sorry these are OFFLINE
cat OFFLINE.txt
rm ONLINE.txt OFFLINE.txt

Thanks for helping guys!

Answer 2

I think you want something like this:

#!/bin/bash
while read m; do
   echo Checking MAC address: $m
   sudo ifconfig en0 ether $m
   sudo ifconfig en0 down
   sudo ifconfig en0 ether up
   sleep 6
   ping -c 3 www.google.co.in
   if [ $? -eq 0 ]; then
      echo Ping successful
   else
      echo Ping failed
   fi
done < MACs.txt

where MACs.txt looks like this:

11.22.33.44.55.66
22.33.44.55.66.77
33.44.55.66.77.88

Updated Answer

If you want it a little bit more streamlined, you might prefer this version which doesn't always wait 6 seconds - instead it pings up to 10 times with 1 second between pings and stops immediately if the ping is successful so it should be quicker.

#!/bin/bash
while read m; do
   echo Checking MAC address: $m
   sudo ifconfig en0 ether $m
   sudo ifconfig en0 down
   sudo ifconfig en0 ether up
   # Ping up to 10 times, stopping immediately if successful
   success=0
   for i in {1..10}; do
      ping -c 3 -t 1 www.google.co.in > /dev/null
      if [ $? -eq 0 ]; then
         success=1
         break
      fi
   done
   if [ $success -eq 1 ]; then
      echo Success: $m
   else
      echo Fail: $m
   fi
done < MACs.txt

Answer 3

You can use arpwatch to keeps track for ethernet/ip address pairings. You run it like this:

arpwatch -i eth0

And if you want to check the logs:

tail -f /var/log/syslog

Output:

Nov 10 15:59:34 debian arpwatch: new station 192.168.1.2 0:17:9a:a:f6:44 eth0

Then you can do a bash script more easy.

A few examples like... Find the last log of a MAC

tail -f /var/log/syslog | egrep -i xx:xx:xx:xx:xx:xx

extract the time of that log

tail -f /var/log/syslog | egrep -i xx:xx:xx:xx:xx:xx | awk '{print $3}'

or something more useful like the ip

tail -f /var/log/syslog | egrep -i xx:xx:xx:xx:xx:xx | awk '{print $8}'