CHAP problem with PPPoE server

Phil Mayers p.mayers at
Wed Mar 9 18:35:52 CET 2011

On 09/03/11 10:03, Paul Thornton wrote:
> This is the part that is the mystery.  There seems to be scarce
> information out there about how pppd functions when using radius as a
> back end (apart from it should 'just work') - most of the documentation
> about pppd relates to dial-up as a ppp client or a server without using
> radius.

The pppd radius plugin basically replaces the built-in functions in pppd:


...with it's own, radius-based versions (not those names - something 
else). It (like most of pppd) is a horrible bit of code, but it does 
basically work ;o)

You need to configure pppd itself to use "chap". This is independent of 
any radius config - it'll be something like:



...or those same options on the pppd command line, or however your PPPoE 
daemon takes them.

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