dhcpcd-discuss

Hi Jason

On 23/06/2017 22:03, Jason A. Donenfeld wrote:
> More generally, I'd invite you to check out how dhcpcd behaves with
> eth0 and wlan0, when the same IP is assigned to both, via dnsmasq's
> dhcp-host option. From the man page:
>
>                As a special case, in DHCPv4, it is possible  to  include
>               more    than    one   hardware   address.   eg:   --dhcp-
>               host=11:22:33:44:55:66,12:34:56:78:90:12,192.168.0.2 This
>               allows an IP address to be associated with multiple hard‐
>               ware addresses, and gives dnsmasq permission to abandon a
>               DHCP  lease to one of the hardware addresses when another
>               one asks for a lease. Beware that  this  is  a  dangerous
>               thing  to  do,  it will only work reliably if only one of
>               the hardware addresses is active at any time and there is
>               no  way for dnsmasq to enforce this. It is, for instance,
>               useful to allocate a stable IP address to a laptop  which
>               has both wired and wireless interfaces.
>
> AFAIK, this doesn't operate properly with dhcpcd.

What dhcpcd is supposed to do is to use the lease on the interface with 
the lowest metric when there are multiple active leases with the same IP 
address.

It has supported this for quite some time now, but dhcpcd-7 has changed 
a lot of internals.

Roy