dhcpcd-discuss

On Saturday 15 August 2015 01:20:02 Roy Marples wrote:
> On 2015-08-15 00:52, Walrath, Paul wrote:
> > I'm seeing another unexplainable behavior that may be tied in with
> > this.  If I change my DHCP servers from the DHCPv6 server providing
> > DHCPv6 Option 39 Client FQDN to having the DHCPv4 server providing
> > DHCPv4 Option 12 Hostname and DHCPv4 Option 15 Domain Name to my
> > device then do an ifdown followed by an ifup on my device's network
> > interface, the domain name changes (/etc/resolv.conf) to the DHCPv4
> > provided name but the host name remains the same.  If I power-cycle my
> > device, the host name gets updated.
> 
> This won't work, dhcpcd won't magically unset the hostname, thus
> probably won't change over.
> I don't see a good way of doing this, but not thought about it too much
> either.

The only way this could work is like so

DHCPv4 lease sets hostname foo
DHCPv6 has no hostname

To change over hostname control to DHCPv6

DHCPv4 sets hostname foo
DHCPv6 sets hostname foo

Both names are now in agreement so handover can take place

DHCPv4 has no hostname
DHCPv6 sets hostname bar

Because the prior DHCPv6 lease set hostname foo (ie the currently assigned 
hostname), we know we can change it to bar so this should work.

Makes sense?

Roy