Thank you both, Phil and Hoercher, what I did is what you suggested, using FreeRADIUS attributes to distinguish each access point and I used the CalledStationId in particular, which is the MAC address of each AP - this is as unique as it gets. Thanks alot. On 11/19/06, K. Hoercher <wbhoer@gmail.com> wrote:
On 11/19/06, liran tal <liransgarage@gmail.com> wrote:
I'll try to elaborate on this... There are two access points deployed in two different locations, they both speak to a central radius sever, it looks like this:
AP1 - DHCP Address Pool 172.19.1.0/24 AP2 - DHCP Address Pool 172.19.2.0/24
ah ok. (nitpick: so the subnet mask /24 is not different, the subnets are *g*)
Now, say user foo got connected to AP1, in the logs I will see he received FramedIPAddress 172.19.1.250 so I will know for a fact that the user is conneccting from AP1 rather than AP2.
Which log? Again, as the issueing of dhcp leases would happen after the associating/authenticating of the user's machine I would not expect Framed-IP-Address to be tranmitted in an Access-Request from an ap to be acted on by freeradius. Actually the other way round would be more common, freeradius sending that attribute to the ap. Maybe it could be part of an accounting message sent by the ap, but that would also be to late to base authentication decisions on in any sane way.
If you happen to have such setup nevertheless, could you show the freeradius debug output?
So I'm asking if there's a better way to do this rather than by configuring different subnets on the dhcp server of the APs. A NASIPAddress is actually a good solution but I'm not going with that cause I can't be sure that it's a static one (some APs receive their "wan" interface address by DHCP which may vary all the time).
Not freeradius related: Does every AP use/have its own dhcpd for the users? If so, they should ensure that no confliciting leases get out by means of relaying to a central server, coordinating between themselves, assigning different ranges of ips or just keeping the leases on different subnets (the last beeing not the best approach, I think, and would also not be needed for freeradius as I tried to explain already and will do, hopefully more completely, below).
Ok, so the mentioned combinations would include NAS-IP-Address to be not part of them. I was talking in general about possible already existing choices you could watch out for.
To do that even more: As to your wish to "distinct", what are your needs related to that distinction: authentication/authorization/accounting? As long as your aps send anything as part of the radius protocol, which is specific to them (which is quite probable) and known a priori (which might rule out NAS-IP-Address, (but why not dhcping fixed addresses, or at least different ranges to them? etc. as completely dynamic ips for aps look a bit awkward to me, not only for the problem at hand)) in the different messages to freeradius, that entitiy can be used (where/how depends on the purpose) to decide between different alternatives.
So any other ideas...
Not really, I would still uphold my statement previously made. To perhaps clarify it a bit: Yes, of course you can configure freeradius to act differently on different inputs. Any more specific suggestions could only arise from you telling what the aps do (other than putting users on different subnets, which is possible too, but not desireable I think) ; more to the point: what (which attributes) do they send in which situations, and what reaction you want in those situations.
regards K. Hoercher - List info/subscribe/unsubscribe? See http://www.freeradius.org/list/users.html