A question for your perusal...
I have a cable modem, and a linux box behind a broadband router. The ISP provides IPs through DHCP, and the IP that my network uses changes from time to time. I like to access my boxen through telnet from work a lot, and the problem is that the IP is always expiring and changing. So here is what I was wondering...

Is there a way for a box behind a firewall to tell what IP address the firewall is using, and more to the point, is there a perl module that anyone has experience using that can divine this info elegantly. My plan is to implement some cron jobbed perl to check the IP address, compare it to a last IP found, and email my office if the IP has changed.

Thanks for the opinions.

Anyway, no drug, not even alcohol, causes the fundamental ills of society. If we're looking for the source of our troubles, we shouldn't test people for drugs, we should test them for stupidity, ignorance, greed and love of power.

--P. J. O'Rourke

In reply to Getting an IP address from DHCP by Snuggle

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.