Using DHCP for Radius on a Cable Modem Plant

[Alan DeKok]

On Aug 21, 2015, at 11:29 AM, John Alcock <john at alcock.org> wrote:
> Has anyone use freeradius and the built-in dhcp server in freeradius for a
> small cable modem plant?

  There are a number of people using it.

> So, my question has to do with documentation.  Most of seems to be dealing
> with version 2, and the main page says.. hey.. do not use version 2 configs
> as a starting space.

  The documentation does need updating for v3.

> Also, documentation seems weak on the new DHCP options.

  Yes sorry.  It should be relatively simple: see raddb/sites-available/dhcp.

> The way I figure it, if I am going to complain about documentation or lack
> thereof, I just need to write some documentation and submit to the group.

  A good "how to" would be nice.  But the wiki has a good start:

http://wiki.freeradius.org/guide/dhcp-for-static-ip-allocation

> That being said, some directions in the right direction would help me get
> started. I have seen documentation on each of the separate items below, but
> not much in tieing it all together.

  That is a problem.

> SQL database (mysql, postgress, I do not care) to keep track of
> information, specifically the MAC address which will be used for
> authentication.

  I'd say use Postgres.  And then the sqlippool module, which works for both RADIUS and DHCP.

> DHCP? Should I use the DHCP built into Radius?  Or outside DHCP server.  I
> kind like the idea of allowing Radius handling it all.

  Me, too.

> So. At the end, I guess I am looking for some general advice on best
> practices of setting this up.

  Read raddb/sites-available/dhcp.   See the sqlippool schema in raddb/mods-config/sql/ippool, and the dhcp_sqlippool module in raddb/mods-available, and the dhcp_sqlippool policies in raddb/policy.d/dhcp_sqlippool.

  That could probably be simplified.  But it should be enough to get you up and running in less than a day.

  Alan DeKok.