[SOLVED] Can I run dnsmasq as boot server in my environment

[deloptes <deloptes@gmail.com>]

john doe wrote:

> On 2/29/2020 6:20 PM, deloptes wrote:
>> john doe wrote:
>>
>>> I would rather look there to get it working with your current setup.
>>>
>>
>> looks like dnsmasq is more cooperative - I don't know how to do it with
>> the current setup :/
>>
>>>> It seems however dnsmasq does the job
>>>> with just few lines in the configuration.
>>>> So I am wondering if I can allocate a range on the dhcp server and
>>>> handle this range via dnsmasq. Perfect would be to keep the working
>>>> part without too many modification as I do not want to regression test
>>>> all the rest.
>>>>
>>>
>>> I don't think you can have two DHCP server running on the same ports, so
>>> I would go one way or the other.
>>
>> yes this is true, but bootp is not the dhcp.
>>
>> Let me precise the question
>>
>> dnsmasq would do the bootp stuff and the dhcp server will provide the ips
>> as usual. I saw one can turn off the bootp in isc-dhcp-server.
>>
>> Is this possible?
>>
>>
> 
> I know that you can disable DHCP and DNS functionalities in Dnsmasq,
> so-in effect living only PXE boot functionality.
> 
> At the risk of being redundant, don't mix both approaches.
> 
> --
> John Doe


The trick was to add following line to the dhcpd.conf

   option vendor-encapsulated-options
6:1:3:a:4:0:50:58:45:9:14:0:0:11:52:61:73:70:62:65:72:72:79:20:50:69:20:42:6f:6f:74:ff;

This could be added to a class, but I have only one rpi4, so added directly
to the client config.

The other trick is to set root-path to the tftp boot directory.

If there is more curiosity what happens on the network, use this

        tcpdump -Xvv  udp port 67 or port 68 or port 69

Amazing!

I would like to know what vendor-encapsulated-options is. The end of it
translates to Raspberry Pi Boot\0. But the first part ... ???
In anycase it does the magic