dhcpcd-discuss

Hi Roy.

After applying these patches I see the device replying to the last lease address during the expired state and there are periodic discover requests being broadcast. This is great.

But when the server comes back online, there is a small problem. I believe that the server is arping the previous lease ip, when the discover comes in the server sees the client is using that ip, then offers a different address. Attached is an example. 

I'm not sure what the solution would be, but the older client appears to periodically unlink the previous ip address, attempt discover, then relink to the old ip.

Thanks.

-----Original Message-----
From: Roy Marples <roy@xxxxxxxxxxxx> 
Sent: Tuesday, September 1, 2020 4:16 AM
To: Matthew Clarkson <mclarkson@xxxxxxxxxxxxxxxxxxxx>; dhcpcd-discuss@xxxxxxxxxxxx
Subject: Re: Extending a lease when dhcp server is offline (similar to lastleaseextend)

On 01/09/2020 12:07, Roy Marples wrote:
> Patch here:
> https://roy.marples.name/cgit/dhcpcd.git/commit/?id=ffb2feb302ecf3600aa905eb78bc864f6a5eb0f5 

And adjusted slightly to close off another code path:
https://roy.marples.name/cgit/dhcpcd.git/commit/?id=16a0f4b9dc21ccc31ff6366e25ee76cf7413cf0d

Attachment: dhcpcd-server-offers-new-ip.pcapng
Description: dhcpcd-server-offers-new-ip.pcapng