Re: Control pppd behaviour

[Ashmath Khan <hashmat.email@gmail.com>]

Thanks James for long explanation.

Let me explain. I am actually looking for a different retry mechanism
for failures. My retry interval would vary depending on the number of
retries. To given an example:
nth retry is to be attempted at (n - 1)3 x 10 secs after previous attempt

So the retry interval is not constant but derived from a formula.

Are such things possible without modifying the code ?

thanks.



On Thu, Feb 11, 2010 at 6:48 PM, James Carlson <carlsonj@workingcode.com> wrote:
> Ashmath Khan wrote:
>> I am not looking for multiple options with which pppd needs to try.
>> Let me give an example, normally if auth fails...it will retry after
>> 'a' seconds for 'n' number of times.
>> What I would need is say it should try after 'a' seconds for first
>> retry, after '2a' seconds for second try after first retry fails and
>> so on..etc. Basically I want to change the retry mechanism. Is there a
>> way to change without changing the code ?
>
> It's still unclear what you're after.
>
> Are you asking about the details of how the protocol itself works?  In
> other words, are you asking about how you can modify the algorithm that
> decides when to send PPP negotiation packets?
>
> If so, then you'll need to change the source code and recompile.  There
> are documented parameters that allow you to change the maximum number of
> retries and the interval between retries, but none that change the
> algorithm used to determine when retries occur.  The algorithm is simple
> and fixed: when the timer expires and there are retries left, the TO+
> event is delivered, and that causes the timer to be restarted and a new
> message to be generated.
>
> Perhaps the real question here is: "what are you trying to do?"  If you
> could explain what higher-level problem you're trying to solve, it might
> be possible for someone to give you a better answer.
>
> Are you trying to work around a problem?  If so, what problem, with what
> symptoms and debug log messages?  Are you trying to interoperate with a
> peer that has bugs?  Are you trying to experiment with PPP itself?
>
> On the off chance that you're trying to "work around" an error message
> such as "LCP: timeout sending Config-Requests", you shouldn't.  That
> message doesn't mean there's anything wrong with the timer algorithm.
> It means that either the physical link isn't working properly or that
> the peer just isn't running PPP at all.  With a dial-up link, it usually
> means that the chat script has failed.
>
> --
> James Carlson         42.703N 71.076W         <carlsonj@workingcode.com>
>