{Latest update: 21 April 2001}

What is it?

The homeip shell script helps you stay updated about the IP that your Cisco 675 DSL router is assigned when configured in PPP mode. It automatically sends an email to whichever email address you specify in the script if you configure it as a cron job in your Linux/UNIX system.


The following are the minimum requirements to run the scripts:
  • Any distribution of Linux. It may also work in FreeBSD and other flavors of UNIX, although I didn't try it yet. What the heck, it may even work in Windows provided that you installed cygwin, but I didn't try that either.
  • The bash shell
  • A copy of expect, which comes with pretty much any Linux distribution these days

How to install and configure

Download the tarball from here, and then enter the regular commands to untar it: tar xzvf homeip.tar.gz. At that point, please take the time to read the README and INSTALL files which explain what to do next. Basically, you only need to open the homeip.sh file and enter the appropriate values for your variables, and then do the same with the telnet.sh script. Finally, go ahead and configure cron to run the homeip.sh script periodically (you will find lots of information on how to configure cron all over the Web).

Future improvements

These are some of the improvements I'd like to add in the future if I find the time... :-)
  • Write some code to allow the script to post the information via FTP tool
  • Automatically change the settings of the Cisco 675 router to adapt to the new situation by reconfiguring the port mappings.
NOTE: this script is not under active development anymore. I have been using a static IP for quite a while now, which makes it very difficult to keep up to date since I cannot truly test it much.


v0.8  (21 April 2001)
      Fixed bug by adding new function to check whether there is connectivity
      to the Cisco router.

v0.7  (5 February 2001)
      Added some security checks for symlink issues, changed the temporary
      files to /var/tmp, added some code to count for possible lack of
      connectivity, made some changes to the logger calls, and tidied up
      the code a little bit by creating some functions.

v0.6  (30 January 2001)
      Changed the location of the temporary file to /var/tmp for portability
      reasons, and also added an $installdir variable to improve its execution
      from cron.

v0.5  (15 December 2000)
      Wrote the code so that the script only sends email when the IP changed,
      and it doesn't act when it didn't change (nice bandwidth saver).

v0.4  (23 September 2000)
      Added logging capability.

v0.3  (4 September 2000)
      Added some simple trap code to handle errors in a graceful manner.

v0.2  (2 September 2000)
      Posted in the Internet for the first time.

Suggestions, bugs, etc.

Any suggestions, bugs, ideas, improvements, etc. please email them to me at <nitebirdz@sacredchaos.com>.

Jesus Ortega (a.k.a. Nitebirdz)
St. Paul, Minnesota (USA)
10 August 2001