[Dnsmasq-discuss] Using dnsmasq for multiple subnets

[David Cooper]

Two updates:

Update 1:
I had a typo in my results. I said "But it does not go to server
3.3.3.3. for the address. " and meant " But it does not go to server
3.3.3.3. for the tftp".

Update 2:
Working more on this, I completely forgot to check the syslog file where
it has been reporting quite a good bit of information. I discovered that
if I change the line
"dhcp-range=set:site1,2.2.0.0,proxy,255.255.0.0" to
"dhcp-range=set:site1,2.2.0.0,2.2.255.255" it worked fine but then also
passed an ip address offer to the machine (which I do not want).

Essentially it looks like if it has a set option and is in proxy mode,
it won't respond to the dhcp request.

Is this by design?

On 8/7/13 1:24 PM, dnsmasq-discuss-bounces at lists.thekelleys.org.uk wrote:
> Hi all!
> 
> Scratching my head here on why this isn't working. I believe I am
> somehow not understanding how the set and tag system works. Hopefully
> someone can point me in the right direction.
> 
> Recently I started using a Network Access Control (NAC) system. This
> system provides DHCP for the isolation network. However, I have a need
> to PXE boot but cannot alter the NAC system. Furthermore I have multiple
> imaging servers that service specific subnets.
> 
> My solution is to provide one dnsmasq server to point certain subnets to
> the correct imaging server for PXE boot.
> 
> I have:
> - setup dnsmasq 2.59 on Ubuntu 12.04 (precise pangolin) LTS on ip
> address 1.1.1.1/16 from the cd-rom repository.
> - added the "ip helper-address 1.1.1.1" on the 2.2.0.0/16 network.
> - For purposes of the example, my imaging server is 3.3.3.3
> - deleted the dnsmasq.conf and replaced it with the following contents.
> 	port=0
> 	log-dhcp
> 	dhcp-boot=pxelinux.0
> 	dhcp-no-override
> 	pxe-prompt="Press F8 for boot menu", 0
> 	dhcp-range=set:site1,2.2.0.0,proxy,255.255.0.0
> 	pxe-service=tag:site1,X86PC, "Boot from blah",pxelinux,3.3.3.3
> 	dhcp-boot=tag:site1,pxelinux.0,site1.net,3.3.3.3
> 
> I boot the machine, get the dhcp address from the isolation network, get
> the proxy ip for 1.1.1.1. But it does not go to server 3.3.3.3. for the
> address.
> 
> Adjusting the dnsmasq.conf, I remove the set anda tag options and it
> works fine. While this is obviously a solution, when I go to add another
> subnet to the mix I will need to send a different server ip.
> 
> I believe the set commands set an identifier. That identifier is used by
> the tag lines to denote when they should act.
> 
> What am I doing wrong?
> 

-- 
David R. Cooper
Network Analyst
East Stroudsburg Area School District
Technology Learning Center
2002 Milford Road
East Stroudsburg, PA 18301
http://www.esasd.net
david-cooper at esasd.net
570-424-8500 x1614