[Dnsmasq-discuss] re-reading dhcp options without restart

[Simon Kelley]

Carlos Carvalho wrote:
> Back in June when 2.40 was at test12 and --dhcp-hostsfile was
> introduced I said that I also need to re-read dhcp options. Here's
> what Simon said:
> 
>  >>  >http://www.thekelleys.org.uk/dnsmasq/test-releases/dnsmasq-2.40test12.tar.gz
>  >>  >
>  >>  >has this code: see the --dhcp-hostsfile switch.
>  >> 
>  >> Unfortunately that's not enough :-( :-( It only allows one to read
>  >> dhcp-host declarations but it's also necessary to allow dhcp-option
>  >> specifications. My dhcp-hosts file consists of a series of
>  >> 
>  >> dhcp-host=name,MAC,id:*,net:name
>  >> dhcp-option=name,vl7,3,router-ip
>  >> some other options
>  >> 
>  >> Allowing changes to the host declaration only is somewhat restrictive...
>  >
>  >There's a limit as to what can be changed on the fly: depending on how 
>  >data structures get used. (When re-reading a file it's first necessary 
>  >to remove stuff which came from the last read: if that's in use 
>  >elsewhere it all breaks....)
> 
>  >> Also I'd need to re-read addn-hosts, like it's done with /etc/hosts.
> 
> This I can do without but it'd be good for completeness (and symmetry).

That's already there, I think.
> 
>  >It's probably possible to do options, dhcp-range is not possible.
> 
> Agreed about dhcp-range. However having the possibility to re-read the
> options would be very useful here because it'd reduce the number of
> restarts by a factor of 10 at least.
> 
> So you can consider this as a feature request :-)

Ack: I'll have a think about it.

> I'm coming back to this subject because of the possibility of using
> dnsmasq for the central server. Presently it has all names in
> /etc/hosts and dnsmasq is used only for client queries (because of
> its wonderful localization feature). The problem is that a few
> machines can take a different IP depending on the location. Since
> Simon observed a few days ago that dnsmasq can handle this, I'd like
> to remove the clients from /etc/hosts and make the central server also
> use dnsmasq. And then I'd not like to restart it often...
> 

Cheers,




Simon.
Simon.