create the original file
ifconfig eth0|grep inet > test
then in the cronjob
ifconfig eth0|grep inet > test1
compare them
diff test test1 > test2
Someone better at scriptiong than me will have to correct this.
if [ "cat test2" = "" ]; then
echo no change
else
mail [EMAIL PROTECTED] < test2
rm -f test
cp test1 test
fi
from the top of my head. Now as I indicated, I know for sure that the IF
statement is wrong. Either someone else will rewrite, or google will help
you.
That should work.
:)
And now you know why I don't write code.
Kev.
----- Original Message -----
From: "Jesse Kline" <[EMAIL PROTECTED]>
To: "CLUG TALK" <[EMAIL PROTECTED]>
Sent: Tuesday, February 11, 2003 12:38 PM
Subject: RE: (clug-talk) Dynamic DNS help?
> On Tue, 2003-02-11 at 10:47, Curtis Sloan wrote:
>
> > Thus I poked around dhcpcd to see if it would let me know when it
> > makes/receives a change in address (dhcpcd as an example, other DHCP
clients
> > exist). If anyone knows a better tool/way, I'd love to hear it.
>
> Looking through my own personal archive I found some messages from back
> in November when I was complaining that I couldn't ssh into my box
> because my IP address had changed. Here are the responses that I got:
> Kevin Anderson wrote:
> "Create a cronjob that:
>
> writes your IP address to a file called current every hour.
> Compare the contents of current with the contends of old.
> if they are different, then mail [EMAIL PROTECTED] < current
> copy current over old
> end
>
> Then create the original old file for yourself.
>
> Depending on how much you value SSH access, have it check hourly.
>
> Kev."
> This sounds like a good idea. I'm not quite sure how to implement this,
> but if the router has the public IP address then the cronjob could run
> ifconfig and pull the IP, then it shouldn't be too hard to compare two
> IP addresses and take action if they are different. I also got this
> response from Richi Plana:
> "Or, if you're using dhclient, modify the /sbin/dhclient-script script.
> There's a section there that actually handles a change in IP address.
> Just email the contents of $new_ip_address to your external mail
> account."
> This one may relate more directly to what you are trying to do.
>
> I hope this helps,
>
> Jesse
>
>
>
