Option 82 & limit lease 1

[Glenn Satchell]

As head honcho at ISC, anything David says is surely more accurate than 
my notes. I didn't try that (left as an exercise for the person with the 
problem - how much time do you think I have?)

In this case David's statement is very clear, and I don't know the 
answer to your original question...

regards,
-glenn

On 04/29/10 02:32, Denis Laventure wrote:
> Hi Glenn,
>
> I get this error if I try concat with host-identifier:
>
> /uqac/dhcp/dhcpd.conf line 248: host-identifier must be an option
> host pc          { host-identifier concat(
>                                             ^
> Configuration file errors encountered -- exiting
>
> Here's my host config:
> host pc          { host-identifier concat(option agent.remote-id, option agent.circuit-id) 0:6:0:13:19:91:3b:0:0:4:1:2a:2:4; fixed-address 172.18.4.32; }
>
> This one with only agent.circuit-id works:
> host pc2         { host-identifier option agent.circuit-id 0:4:1:2a:2:4; fixed-address 172.18.4.33; }
>
> Did you tried it yourself or you just figure it would be ok because it's an option?
>
> In a post from David W. Hankins:
> (https://lists.isc.org/pipermail/dhcp-users/2009-November/010339.html)
>
> Note that this uses the entirety of a named option, it doesn't take an
> arbitrary data-expression (no substring()'s, etc).
>
> Denis
>
> -----Message d'origine-----
> De : dhcp-users-bounces+denis_laventure=uqac.ca at lists.isc.org [mailto:dhcp-users-bounces+denis_laventure=uqac.ca at lists.isc.org] De la part de Glenn Satchell
> Envoyé : 27 avril 2010 20:43
> À : Users of ISC DHCP
> Objet : Re: Option 82&  limit lease 1
>
> The host-identifier is a data-expression, so you can use any of the
> operators in the dhcp-eval man page to combine them. For example
>
> host-identifier concat( option agent.remote-id, option agent.circuit-id
> ) "[some_static_RID_some_static_CID]";
>
> You could also sue substring if there was a unique key or prefix within
> the remote_id.
>
> regards,
> -glenn
>
> On 04/28/10 05:54, Denis Laventure wrote:
>> Hi Marc,
>>
>> Thanks for the tip on the host-identifier trick!
>>
>> It's ok if you only need agent.circuit-id, but how do you manage
>> agent.circuit-id from different agent.remote-id?
>>
>> Denis
>>
>> *De :* dhcp-users-bounces+denis_laventure=uqac.ca at lists.isc.org
>> [mailto:dhcp-users-bounces+denis_laventure=uqac.ca at lists.isc.org] *De la
>> part de* Marc Perea
>> *Envoyé :* 22 avril 2010 17:38
>> *À :* dhcp-users at isc.org
>> *Objet :* Re: Option 82&  limit lease 1
>>
>>>
>>> From: Scott Baker<scott at perturb.org>
>>> Subject: Re: Option 82&  limit lease 1
>>> I think maybe I missed part of the conversation. What's "option matching"?
>>
>> Option matching appears to be a new feature in 4.2.x. It allows you to
>> define a host by an option, instead of (in addition to?) by a
>> mac-address. For a service provider, like us, this is a HUGE step
>> forward (thanks btw to ISC for adding this feature). We've seen
>> improvement of 2 orders of magnitude in performance over our old
>> configuration on 3.1.2 both in restart times of the daemon and in
>> DORA/second.
>>
>> As example, we used to define a class that matched on a specific option
>> 82 (agent.circuit-id). Then we'd build a pool. Then we'd build a range
>> (of 1 IP). Then apply the filter of our class to the range. For tens of
>> thousands of customers, that's a very large conf file. And it's slow,
>> _really_ slow.
>>
>> With 4.2, one can define a host and give it a fixed address. Done. It's
>> very, _very_ nice. Smokin' performance too.
>>
>> And because I couldn't find it documented anywhere (man pages referred
>> to ipv6, but this works in ipv4 too), it goes like:
>>
>> host [some_unique_host_name] { host-identifier option agent.circuit-id
>> "[some_static_CID]"; fixed-address [a.b.c.d]; } #[some_customer_identifier]
>>
>> HTH
>>
>> --Marc