forcing new dynamic ip address

Frank Leonhardt (m) frank2 at
Fri Oct 13 11:52:51 UTC 2017

On 8 October 2017 13:37:30 BST, Erwan David <erwan at> wrote:
>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
>> 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
>> cable into the un-used NIC and make the appropriate config changes
>> 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
>> 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.

Hate to be a pendent, but it may not be a DHCP server giving you the IP address unless you're running Ethernet. In some parts of the world people do run PPPoE instead of ATM, so it might conceivability work this way. Most DSL use LCP to configure IP address IME. Once you go past the modem socket it doesn't look like Kansas any more. 

Sent from my Android device with K-9 Mail. Please excuse my brevity.

More information about the freebsd-questions mailing list