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Subject: Re: forcing new dynamic ip address
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From: Erwan David <erwan@rail.eu.org>
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Date: Sun, 8 Oct 2017 14:37:30 +0200
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Le 10/08/17 à 14:28, Ernie Luzar a écrit :
> Hello List;
> 
> I have a "home service" account from my ISP. The ISP issues an dynamic
> ip address which has not changed in 12 years.
> 
> My host has 2 NICs, one which is not used. I know if I plug the internet
> cable into the un-used NIC and make the appropriate config changes and
> reboot I will get a different dynamic ip address.
> 
> Is there a simpler way to expire the lease to force the ISP dhcp to
> refresh with a different dynamic ip address?
> 
> The goal is to have a cron job that gets a different dynamic ip address
> assigned to my host's front door every a week.
> 
> Just another level of security to make it very hard for the script
> kiddies from finding any open ports I may have.
> 
> Thanks for the help.
> 

DHCP protocol states that the server should try to give you the same IP
address. And dhcp servers keep track of the addresses they allocated in
the past, to give them back if possible.