Re: pppoe uplink goes down several times a day, what is wrong

[Jelle de Jong <jelledejong@powercraft.nl>]

Hi James,

Thank you for taking the time to look at my problems.

James Carlson wrote, on 21-12-09 14:49:
> Jelle de Jong wrote:
>> I am wondering what I am doing wrong, is there something I should
>> change on the software side? Should I change the modem configuration?
>> Stop using PPPoE?
> 
> Your debug log shows the following:
> 
> Dec 21 06:37:54 sammy pppd[2954]: primary   DNS address 213.75.63.36
> Dec 21 06:37:54 sammy pppd[2954]: secondary DNS address 213.75.63.70
> Dec 21 08:32:56 sammy pppd[2954]: No response to 4 echo-requests
> Dec 21 08:32:56 sammy pppd[2954]: Serial link appears to be disconnected.
> Dec 21 08:32:56 sammy pppd[2954]: Connect time 115.1 minutes.
> 
> That indicates that your link was up and working for almost two hours,
> and then was torn down because the ISP's server suddenly stopped
> responding to LCP Echo-Request messages from your system.
> 
> If it happens this way every time, then I would suspect that your ISP
> may have set a time limit on connections.  Some ISPs are known for doing
> such things, especially those that have a dial-up background.  They view
> their service as being "on-demand" and thus an always-connected client
> is one that's abusing the terms of service.  (That having everyone
> connected all the time costs no more than having them connect on demand
> doesn't seem to factor into those calculations.  There's no technical
> accounting for business rules ...)

The disconnection interval seems random, as you can see the logs
showed two disconnects this day.

# grep -i pppd /var/log/syslog | grep -i time
Dec 21 06:37:24 sammy pppd[2954]: Connect time 2681.4 minutes.
Dec 21 08:32:56 sammy pppd[2954]: Connect time 115.1 minutes.

The connection is a G.SHDSL 2048:2048 1:1 business connection very
expensive by the biggest ISP in our country (not saying the ISP is
good) I don't think they have a connection time limit?

> If it seems to be "random" rather than a fixed interval, then that's
> probably not the problem.  It's possible that the ISP's server is
> crashing occasionally or that it's experiencing some sort of
> communications problem or that the path between you and that server (the
> ATM network) is itself unreliable.  The key information that's needed to
> identify such a problem would be on the ISP's systems (or may need some
> investigation and analysis).

I changed the Siemens 5890 provided by the ISP with a DrayTek Vigor
3100. The Siemens modem did NAT and was not transparent enough. But by
doing this the support level provided by the ISP drops to a minimum...

> The bottom line, I think, is that your ISP is the only entity that can
> investigate and solve the problem properly.  If your ISP doesn't take
> your complaints about reliability seriously, then it's time to find a
> new one.

I got a vendor locking, The current DSL is pre-fibre solution because
the completion of the fibre internet connection is taking longer then
anticipated, and the ISP is the only fibre capable provider in the
Netherlands for the location of the new office.

> (As for PPPoE, I'd certainly recommend avoiding that if you can. It's a
> horrible mess as a protocol. In this case, though, I don't think it's
> to blame for your problems.)

Is there a way to be more sure about PPPoE not being the issue. Can
there be something wrong with the LCP Echo-Request messages?

I know PPPoE is a horrible mess. I prefer 1483 bridged IP LLC, but I
can't use it in this case.

Thanks in advance,

Best regards,

Jelle