[Dnsmasq-discuss] ignoring unknown devices ..
Ben
abnormaliti at clivepeeters.com.au
Thu Nov 22 01:04:42 GMT 2007
richardvoigt at gmail.com wrote:
>
> On Nov 16, 2007 12:50 AM, Ben <abnormaliti at clivepeeters.com.au
> <mailto:abnormaliti at clivepeeters.com.au>> wrote:
>
> I need to setup dnsmasq to ignore unknown devices and I have been able
> to do so with 2.40 but I have a configuration issue that I think
> may be
> a bug.
>
> Here is what i want to have.
>
> dhcp-range= 10.7.5.100 <http://10.7.5.100>,10.7.5.254
> <http://10.7.5.254>,24h
> dhcp-ignore=#known
> dhcp-hostsfile=/etc/dnsmasq.d/#hostsfile#
>
> dhcp-host=tc01, 10.7.5.13 <http://10.7.5.13>
> dhcp-host=tc02,10.7.5.14 <http://10.7.5.14>
>
> This should, in theory, allocate IPs to devices with MAC addresses
> listed in the '#hostsfile#' and devices named 'tc01' and 'tc02'. But
>
>
> MAC addresses are normally listed in /etc/ethers, not /etc/hosts. I
> see you're using the brand new hostsfile feature, I don't know what
> version Simon implemented that but I think 2.40 is new enough. What
> format are the lines in the #hostsfile#? If you are using a
> hostsfile, why do you have dhcp-host lines in the main config?
The '#hostsfile#' file is just a list of MAC addesses, nothing else.
The hostsfile is being used to restrict the devices that addresses are
served too, not allocate fixed IP to anything, the "dhcp-host" entries
in the main config are the devices i want to allocate fixed IP's too.
The hostsfile is filled from a database of MAC addresses of all devices
we have and changes regularly.
>
>
>
> when "dhcp-ignore=#known" is defined 'tc01' and 'tc02' are ignored.
>
> This config works, but requires the MAC for 'tc01' to be defined.
>
> dhcp-range=10.7.5.100 <http://10.7.5.100>,10.7.5.254
> <http://10.7.5.254> ,24h
> dhcp-ignore=#known
> dhcp-hostsfile=/etc/dnsmasq.d/#hostsfile#
>
> dhcp-host=00:20:4a:9c:52:c2,10.7.5.13 <http://10.7.5.13>,tc01
>
> So what i am looking for is to be able to use "#known" and
> "hostsfile"
> as well as allocate fixed IPs to devices by name.
>
>
> I think you need to put the fixed IPs into the hostsfile along with
> the MAC address. Or are you trying to match against the client
> supplied ID? That can't be trusted.
>
The problem is not the "hostsfile" it is the 'dhcp-ignore=#known'. When
'dhcp-ignore=#known' is defined the client supplied hostname is not matched.
The man page says "When a host matches any dhcp-host directive (or one
implied by /etc/ethers) then the special network-id tag "known" is set.
This allows dnsmasq to be configured to ignore requests from unknown
machines using *--dhcp-ignore=#known"
*It appears the "any dhcp-host directive" may not be accurate because
'dhcp-host=tc02,10.7.5.14 <http://10.7.5.14>' doesn't appear to work.
Is this a bug or by design? if it is design the man pages needs
updating to clarify the limitations of 'dhcp-ignore=#known'.
Ben
More information about the Dnsmasq-discuss
mailing list