[Dnsmasq-discuss] problem setting default router using tags and MAC address wildcards (was Re: Using dnsmasq to issue IP addresses based on MAC address ranges)

[Jeff Croft]

> Message: 3
> Date: Sat, 18 Apr 2009 01:26:50 +0000
> From: "richardvoigt at gmail.com" <richardvoigt at gmail.com>
> Subject: Re: [Dnsmasq-discuss] Using dnsmasq to issue IP addresses
>         based on        MAC address ranges
> To: Jeff Croft <jeffc at truste.com>
> Cc: "dnsmasq-discuss at lists.thekelleys.org.uk"
>         <dnsmasq-discuss at lists.thekelleys.org.uk>
> Message-ID:
>         <2e59e6970904171826p58ed9d86r3128358c34263e31 at mail.gmail.com>
> Content-Type: text/plain; charset="windows-1252"

> Does the dnsmasq host OS have an address in the 172.17.0.0 range statically
> configured on the interface where the requests arrive?

Ah, bringing up an interface alias for the 172.17 network fixed it right up.
(duh!). Thx much.

I'm still having a problem with this config, though:

dnsmasq is sending its own IP address as the default router, but only for
172.16.0.0/16 addresses. For 172.17.0.0/16 addresses, it works correctly.

(dnsmasq is running on 172.16.0.10 and alias 172.17.0.10)
(default router is another physical machine on 172.16.0.11 and alias
172.17.0.11)

Here's the config:

dhcp-range=net:vmiphys,172.16.1.50,172.16.200.250,255.255.0.0,12h
dhcp-range=net:vmivirt,172.17.1.50,172.17.200.250,255.255.0.0,12h

dhcp-host=*:*:*:*:*:*,net:vmiphys
dhcp-host=00:50:56:00:*:*,net:vmivirt

dhcp-option=net:vmiphys,option:dns-server,172.16.0.10
dhcp-option=net:vmivirt,option:dns-server,172.17.0.10

dhcp-option=net:vmiphys,option:router,172.16.0.11
dhcp-option=net:vmivirt,option:router,172.17.0.11

So, when I renew a lease for a machine in 172.17.0.0/16, it gets 172.17.0.11
as the default route. That's what I want. However, when I renew a lease for
a machine in 172.16.0.0/16, it gets 172.16.0.10, which is incorrect. Same
thing happens for both Windows and Linux clients.

Any ideas?

Thanks again,
    Jeff Croft


> On Fri, Apr 17, 2009 at 11:31 PM, Jeff Croft <jeffc at truste.com> wrote:
> 
>>  Hello --
>> 
>> I?m using dnsmasq v2.41 to issue addresses in two different networks.
>> 
>> What I want is for physical machines to be issued addresses in
>> 172.16.0.0/16 and for VMware virtual machines to get 172.17.0.0/16addresses.
>> I?ve forced all the VMware instances to have MAC addresses which
>> start with 00:50:56:00.
>> 
>> I?m using the following config lines:
>> 
>> dhcp-range=net:vmiphys,172.16.1.50,172.16.200.250,255.255.0.0,12h
>> dhcp-range=net:vmivirt,172.17.0.50,172.17.200.250,255.255.0.0,12h
>> dhcp-host=*:*:*:*:*:*,net:vmiphys
>> dhcp-host=00:50:56:00:*:*,net:vmivirt
>> 
>> which I had hoped would do what I described above.
>> 
>> What happens, however, is that any machine with a MAC address which does
>> not match 00:50:56:00:*:* receives an address in the 172.16.0.0/16network,
>> but any machine matching 00:50:56:00:*:* causes dnsmasq to issue an
>> error like this:
>> 
>> DHCPDISCOVER(eth0) 169.254.34.228 00:50:56:00:00:d7 no address available
>> 
>> and the virtual machine doesn?t get an IP address.
>> 
>> Any suggestions?
>> 
>> Thanks much for some great software.
>> 
>>             Jeff Croft