DDNS with host declarations

[DESEtech - German P. Santillan]

> -----Original Message-----
> From: dhcp-users-bounce at isc.org [mailto:dhcp-users-bounce at isc.org] On
> Behalf Of Glenn Satchell
> Sent: Sunday, October 29, 2006 9:01 AM
> To: dhcp-users at isc.org
> Subject: Re: DDNS with host declarations
> 
> 
> >Date: Sun, 29 Oct 2006 12:43:46 +0100 (MET)
> >From: Jan Engelhardt <jengelh at linux01.gwdg.de>
> >To: dhcp-users at isc.org
> >Subject: Re: DDNS with host declarations
> >
> >>
> >>See the section in dhcpd.conf on classes. You can define a single class
> for
> each
> >>host based on the mac address. Then create a pool with a single IP
> address in
> >>the range. Something like this:
> >>
> >>class "xp" {
> >>  match if hardware = putsomethinghere;
> >>}
> >>
> >>subnet 192.168.234.0 255.255.255.0 {
> >>  ...
> >>  pool {
> >>    allow members of "xp";
> >>    range 192.168.234.2;
> >>  }
> >>  ...
> >>}
> >
> >Hm there is a slight problem:
> >
> >class "xp" { match if binary-to-ascii(16, 8, ":", hardware) =
> >"00:0C:29:93:C6:21"; }
> >subnet ... {
> >  range 192.168.234.10 192.168.234.40;
> >  pool { allow members of "xp"; range 192.168.222.41; }
> >}
> >
> >The client always gets the IP address it used before (234.20) rather
> >than picking up .41. Is this because of the unconditional range
> >statement?
> >I also tried with `match if 1=1` but it won't get .41.
> >
> >
> >>Which can be quite clumsy if you need to have more than a few hosts
> >>defined this way.
> >
> >Well it looks a little nicer than having to put the IP in _two_
> >different places (dhcpd.conf and named db).
> >
> >
> >	-`J'
> >--
> >
> 
> I realiased after I sent the last message that you also need to exclude
> the class from any other ranges. Also you can simplify the match
> statement (note no quotes around the mac address, see dhcp-eval man
> page, the leading 01 is interface type and 01 is ethernet) like this:
> 
> class "xp" { match if hardware = 01:00:0C:29:93:C6:21; }
> subnet ... {
>   pool {
>     deny members of "xp";
>     deny members of "another1";
>     range 192.168.234.10 192.168.234.40;
>   }
>   pool { allow members of "xp"; range 192.168.222.41; }
>   pool { allow members of "another1; range 192.168.222.42; }
> }
> 
> If you allow a particular class that implies denying all other classes.
> 
> The range you offer in all the pools must be valid within the subnet,
> else you will get an error from dhcpd. You've got 192.168.234.x and
> 192.168.222.y so I guess it's not a /24 subnet.
> 
> regards,
> -glenn
> --
> Glenn Satchell     mailto:glenn.satchell at uniq.com.au | Some days we are
> Uniq Advances Pty Ltd         http://www.uniq.com.au | the flies;  some
> PO Box 70 Paddington NSW Australia 2021              | days we  are the
> tel:0409-458-580  tel:02-9380-6360  fax:02-9380-6416 | windscreens...
> 
> 
> 
> 

The easy way

host foo {
	hardware ethernet xx:xx:xx:xx:xx:xx;
	fixed-address yyy.yyy.yyy.yyy;
	option host-name "foo";
	ddns-hostname "foo";
	ddns-domainname "example.com";
}

This static entry sends a DDNS Update to BIND as Lease Transaction.
It Works!

Germán P. Santillán
Administrador de Redes
Jefe del Dpto. Técnico
DESETech Argentina S.A.
San Martín 133 - CP: B8000FIC
Bahía Blanca - Argentina
Tel/Fax: +54 (291) 456-5642
gsantillan at desetech.com.ar
http://www.desetech.com.ar