[systemd-devel] Changing configurations with networkd

[Michael Olbrich]

On Thu, Jul 24, 2014 at 02:05:24PM +0200, Marcel Holtmann wrote:
> > Right, I spoke too quickly. What I don't want is to preserve state
> > between reboots, preserving it between restarts of networkd would
> > indeed be fine. We already serialize the dhcp leases to /run, so I'd
> > be happy to take a patch to deserialize these again when networkd
> > starts.
> 
> I am not sure this is useful either. It feels like a bandaid for the time
> where networkd does not have an API to reload configuration changes. Killing
> networkd should give you a clean start from the configuration files and not
> magic cached value somewhere. Otherwise you end up with funny side effects
> all the time and have to explain to users to clear some /run states. Or ask
> them "to switch the computer off and back on again".
> 
> When you are opting for DHCP instead of static addresses, then there is
> really no guarantee for addresses staying the same. At least not for the
> client to know. So unless you own the DHCP server and configure it with
> static assignment. In all cases you have to confirm with the DHCP server that
> you address is still valid.

Getting a new IP address is not the biggest problem. But right now, when
the valid_lft for the _old_ address is over, then then _new_ address is
removed as well and the interface has no address at all! That is not
acceptable. I can live with a different new address for now, but not with
no address at all.

Michael

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