This program gets for your external IP address, checks it against your "saved" IP address and, if a difference is found, emails you the new IP. This is useful for servers at residential locations whose IP address may change periodically due to actions #by the ISP.

[config] = path to an IPWatch configuration file

1. python3 ipwatch.py [config]
2. ./ipwatch.py [config]
3. python3 ipwatch.py config.txt
4. ./ipwatch.py config.txt

ipwatch requires Python to run. On Debian based systems you can install python3 by running

sudo apt install python3

ipwatch uses a config file to define how to send an email. An example and description is below. A similar config file is in the repo as example_config.txt. You should copy it by running something like sudo cp example_config.txt config.txt and then modify config.txt. It is recommended that you adjust the permissions of your config file so that no one but you and/or root can read it since it will contain the sender email password.

sender=Bob Sender                   #this is the name of the email sender
[email protected]    #this is the email address the email will be sent from
sender_username=bobsender           #this is the username (in this example gmail username) of the sender
sender_password=password1           #this is the password (in this example gmail password) of the sender
receiver=Tom Receiver               #this is the name of the recipient
[email protected] #this is the email address of the recipient
subject_line=My IP Has Changed!     #this is the subject line of the sent email
machine=Test_Machine                #this is the name of the machine sending the email
smtp_addr=smtp.gmail.com:587        #this is the SMTP address for the sending email server (in this case gmail)
save_ip_path=/opt/ipwatch/oldip.txt #this is the location where the saved ip address will be stored
try_count=10                        #this defines how many times the system will try to find the current IP before exiting
ip_blacklist=192.168.0.255,192.168.0.1,192.168.1.255,192.168.1.1  #this is a list of IP address to ignore if received

ipwatch works best when setup as a cronjob. It assumes that you've cloned the ipwatch repo into /opt/ipwatch and that your config file is in the same location. You can access root's crontab by running

sudo su
crontab -e

Below is an example crontab entry to run ipwatch once per hour.

00 * * * * /opt/ipwatch/ipwatch.py /opt/ipwatch/config.txt

If you want to/need to run the cronjob as an unprivileged user you'll have to ensure that your user has execution privileges for ipwatch.py and can write to the save_ip_path file defined in your config file.

If you use Gmail as your sending email service then you'll have to enable Less secure app access to allow ipwatch to send emails. You can read more about this at https://support.google.com/accounts/answer/6010255?hl=en. You can enable Less secure app access by visiting https://myaccount.google.com/lesssecureapps. Chances are you'll also be blocked, by Gmail, the first time you try try to send an email and will receive a Critical security alert saying that a Sign-in attempt was blocked for your linked Google Account at your recovery email/phone #. You'll have to click the Check activity button and say Yes that was me in order to whitelist the ipwatch system.

The original ipgetter.py code came from https://github.com/phoemur/ipgetter. However that repo is gone now. This repo contains a copy of the ipgetter.py file for those who need it. Additionally by keeping ipgetter.py in the same directory as ipwatch.py no additional Python installtion efforts (for the ipgetter module) need be conducted. The version of ipgetter.py in this repository has been updated to remove reference to ip servers that no longer work.

Sean Begley [email protected] 2019-08-10