[RP-PPPoE] rebuild connection

[Insane Laughing Clown]

On 06/11/2011 04:21 AM, Helmut Hullen wrote:
> Hallo,
>
> a school in the neighbourhood uses 3 Linux servers (for 3 separate
> buildungs, it's a kind of boarding school) which all make their WAN
> connection via pppoe.
>
> At some times the pppoe connection is rebuilt about every 20 minutes,
> somtimes even faster, especially on one of the three servers.
> Another server reconnects never the whole day.
>
> Is it possible that some nasty guy (it's always a guy, never a girl)
> makes something like "router reconnect" for faking/changing the IP
> address?
>

The best way to begin looking at this problem, is to look at syslog on 
the client and read the messages there from pppd. It will (should) tell 
you exactly the reason - either it thinks the link is dead, or an idle 
timer expired, or it recevied a 'padt' from the server.

If it's 'idle timeout', well, can't help a whole lot other than to 
either turn it off or pass more traffic (or modify the match criteria)


If it's related to missed lcp-echo responses, then you could be looking 
for dropped packets on your wan link. Its generally stupid to try and 
have lcp-echo-request being sent very often, and especially dumb to drop 
the link on one missed reply (which is a sonic wall hallmark, and some 
other consumer devices do this too. Idiots).

If it's 'recieved padt', well, you'lll need to look at the server logs 
and see why it's kicking you out.

-ILC