dhcpcd-discuss

Just to make sure I understand, I would use the --reboot option set to,
say, 1s. Then the following would happen:

(Assuming no IP currently set)
- DHCP discover would be sent out (immediately or after reboot seconds?)
- If no response to discover within 1s (in this example), the IPv4LL would
start (meaning ARP probe, etc).
- If at some point later a DHCP server does respond to one of the discover
messages, this would supersede the IPv4LL address.

Is the above correct?

If there is already a IPv4LL address and I use --reboot, I assume the
process is still the same as above?

Finally, could you please clarify what setting this to 0s would do? Would
it send discover immediately AND at the same time start the IPv4LL?

On Fri, 17 Jul 2020 at 16:11, Roy Marples <roy@xxxxxxxxxxxx> wrote:

> Hi
>
> On 17/07/2020 14:29, Davesh Patel wrote:
> > Is it possible to configure dhcpcd to do local link addressing in
> parallel to DHCP?
> >
> >   At the moment, dhcpcd sends DHCP discover and waits for that to
> timeout before
> > using the local link IP.
> >
> > But what I'm trying to achieve is for dhcpcd to start to configure local
> link
> > address by sending ARP probe, etc (i.e. not wait for DISCOVER timeout)
> and, at
> > the same time, send a DHCP discover to try to obtain an IP from a DHCP
> server.
> > If a DHCP discover was not available, then it will stick with the
> IPv4LL;
> > otherwise, the DHCP IP would 'overwrite' the IPv4LL IP.
>
> Newer dhcpcd versions do this.
> https://roy.marples.name/cgit/dhcpcd.git/tree/src/dhcp.c#n1872
>
> Basically either the fallback profile or ipv4ll starts after the reboot
> timeout
> from initial discover being sent. The default reboot timeout is 5 seconds.
>
> Roy
>