48 lines
1.8 KiB
Markdown
48 lines
1.8 KiB
Markdown
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# Finding "lost" computers on the web the homebrew way #
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*Jan 23, 2012*
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During the course of updating my home computer I rebooted it because of a kernel update. Later that week at work I went to connect to my home computer and discovered that it's dynamic IP had changed and it's DNS name was invalid.
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So following common advice to "fix a problem two ways to prevent it in the future" I fixed the DNS, but I also wanted an automated way to track my computers when and if their IPs changed.
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So the first thing I needed was shared place to store the IP information. Thinking about it I realized that Dropbox would work well for that. So all I needed was a simple script.
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So the solution was to put a script that determined the IP of the computer in Dropbox and have cron on all the computers run it. Each user can call cron with
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$ crontab -e
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And I created a crontab directory that I could add more scripts to later if need be with and run them hourly with the following entry
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0 * * * * cd /home/dan && run-parts Dropbox/cron
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The script itself was a file called `getip` and it used whatsmyip.com's automation detection script.
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**getip**
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#!/bin/sh
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wget -O /tmp/`hostname`.ip http://automation.whatismyip.com/n09230945.asp
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tmp_file=/tmp/`hostname`.ip
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dst_file=Dropbox/var/log/`hostname`.ip
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if ! diff -q ${tmp_file} ${dst_file} > /dev/null ; then
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`cp ${tmp_file} ${dst_file}`
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fi
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Then I just created `Dropbox/var/log` and installed the crontab on all my computers, and volia, homebrew IP tracking for all my compters accessible to me from anywhere.
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## Comments ##
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**garza** Says:
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January 25th, 2012
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or just use gnudip?
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** Dan Ballard** Says:
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January 27th, 2012
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@garza Assuming you have a server to run it from, which while I do, not everyone may, and in this case, this with dropbox and whatismyip replaces.
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