[Dnsmasq-discuss] Possible bug setting dhcp-option 17

Simon Kelley simon at thekelleys.org.uk
Mon Oct 10 20:52:38 BST 2005


Michael Welle wrote:
> Hi,
> 
> I wanted to net boot some Sparc machines using dnsmasq:
> 
> dhcp-option=17,"/export/elena/root"
> dhcp-boot=/tftpboot/boot.net.netbsd,bootsvr,192.168.42.1
> 
> But setting the root-path doesn't work if the path is longer than 8
> characters. The first condition in do_opt() (rfc2131.c) evaluates to
> true and the operation returns immediately. Is this a configuration
> error or a bug in dnsmasq?

That code is checking for overflow, so it looks like you are generating 
a DHCP packet that's too big. Are you sending lots of options? If so, 
and there's some which aren't necessary, a simple workaround would be to 
trim the number of options so they fit in a minimum-sixed DHCP packet.

There exist facilities in the protocol to negotiate a larger packet size 
when both client and server support it: that's not currently implemented 
in dnsmasq, but it would provide another solution if it were.


Cheers,

Simon.






More information about the Dnsmasq-discuss mailing list