[Dnsmasq-discuss] Supporting more than one domain.

[Simon Kelley]

Ben wrote:
> Simon Kelley wrote:
>> However, it did light a lightbulb, most people who want multiple domains
>> probably want them associated with particular IP address ranges, (or at
>> least can organise things to make that true.) Given that each lease has
>> to have an IP address, that makes mapping from lease to domain perfectly
>> simple. It also makes use of the domain to expand names in /etc/hosts
>> work well (see the --expand-hosts flag)
>>
>> So, here is a suggestion:
>>
>> Elaborate the "domain=" config option so that, as well as
>>
>> domain=example.org
>>
>> the following are also valid
>>
>> domain=example.org,192.168.100.128,192.168.100.180
>> domain=subnet.example.org,192.168.100.0/24
>> domain=anothernet.example.org,2001:db8:100:f101:210:a4ff:fee3:9566/64
>>
>> Multiple domain lines are now allowed, and the smallest address range
>> which matches will be used. The IPv6 version is useful for /etc/hosts
>> and --expand-hosts, it's clearly not used for DHCP (which is IPv4 only
>> in dnsmasq).
>>
>> This has lots of advantages: it's completely backwards-compatible with
>> existing configs, it's straightforward to use, and straightforward to
>> implement.
>>
>> What do people think, would that be sufficiently useful?
>>   
> That would be fine by me.  I would prefer a consistent syntax like
> "net:network-id" but if that isn't practical then i will survive.
>> As part of implementing this, I'd like to try (again) to remove the
>> long-deprecated ISC lease-file reading code. If I don't remove it, it
>> will need work to fit in with the new facilities. I've tried to remove
>> this code before and had complaints; can I assume by now that that code
>> is dead?
>>   
> Fine by me.
> 
> So to make sure i am clear a configuration would look like this, right?
> 
>    domain=sub1.example.com.au,192.168.1.0/24
>    domain=sub2.example.com.au,192.168.2.0/24
> 
>    local=sub1.example.com.au
>    local=sub2.example.com.au
> 
>    dhcp-range=subnet1,192.168.1.100,192.168.1.254,255.255.255.0,24h
>    dhcp-range=subnet2,192.168.2.100,192.168.2.254,255.255.255.0,24h
> 
>    dhcp-option=subnet1,15,sub1.example.com.au
>    dhcp-option=subnet2,15,sub2.example.com.au
> 
>    dhcp-boot=net:subnet1,/pxelinux.0
> 

Right, except that the dhcp option 15 lines are superfluous, they
specify behaviour which will occur by default. This is just an extension
of the existing behaviour: dnsmasq sends the domain automatically.
> 
> While i am at it can i also request that support for the
> "net:network-id" syntax be supported wherever network-id's can be used?
> Using the example above i would like to be able to keep things
> consistent and clearer like this.
> 
>    dhcp-range=net:subnet1,192.168.1.100,192.168.1.254,255.255.255.0,24h
>    dhcp-option=net:subnet1,15,sub1.example.com.au
>    dhcp-boot=net:subnet1,/pxelinux.0
> 

You can, seems sensible to me, I'll add it to the list.

Cheers,

Simon.

> 
> Ben
>