agent.circuit-id (Option-82,2) map to fixed-address

[Henrik Sterndorff Jessen]

I am using dhcp to dish out fixed addresses to users. All users are
connected to cisco switch ports that act as a relay and therefore add
option-82 information to the dhcp query.
 

But I would like to provision the dhcp server so each switch port (and
therefore each user) is assigned a predefined fixed address.

 

That requires that I can map the agent.circuit-id to a fixed address.
"host" entries does not work since I don't know the mac address of the
end users.

 

But I have spend hours on end reading man pages and googling for a way
to do this. Please help me.

 

The only work around I have found is using pools and user groups:

 

class "user-john" {

       match option agent.circuit-id;

}

 

subclass "user-john" 00:04:00:5C:03:04; # This is the cisco switch
option-82 addition.

 

subnet 10.0.0.0 netmask 255.255.255.0 {

        pool {

                allow members of "user-john";

                range 10.0.0.10 10.0.0.10;

                log (info, "subnet hit");

        }

}

 

This seems to work. But I am not shure this scales to 10.000's of users.

 

Thanks in advance

Henrik