How do I point a client to a unicast DHCP server?

[Selahattin CILEK]

I am using FreeRADIUS 3.0.23 to deliver services on pfSense 2.5.2 ( 
FreeBSD 12.2).

Because of some rogue users, I have to issue each device a static IP 
address. I know I can do this thanks to the *dhcp_sqlippool* mod, but 
reading the *dhcp* site provided by the default install, I ran into this 
sentence:

FreeBSD does *not* support binding sockets to interfaces. ...


I know a solution is suggested in the same paragraph, but I will do that 
only as a last resort.


I went ahead and added *dhcp* to *sites-enabled* anyway and then ran 
FreeRADIUS in debug mode (radiusd -X). It was a success:

...

listen {
         type = "dhcp"
         ipaddr = 192.168.1.1
         port = 67
*No "interface" setting is defined.  Only unicast DHCP will work*
}
Listening on auth address 127.0.0.1 port 18127 bound to server 
inner-tunnel-ttls
Listening on auth address 127.0.0.1 port 18128 bound to server 
inner-tunnel-peap
Listening on auth address * port 1812 bound to server default
Listening on acct address * port 1813 bound to server default
Listening on dhcp address 192.168.1.1 port 67 bound to server dhcp
Ready to process requests


So I see I can still use the DHCP functionality, but with a caveat: I 
must somehow get the client to ask for an IP address directly from the 
router's LAN IP address.

So my question is: Can I somehow get the clients to use unicast DHCP? In 
other words, is there some sort of RADIUS attribute I can inject into 
the authentication reply so that it will know where to get its IP from?




-- 
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus