Re: PPPoE Modem hangup after random time - how to debug?

David Balažic
2020-04-27T09:59:25Z

On Mon, 27 Apr 2020 at 04:14, Michael Richardson <mcr@sandelman.ca> wrote:
>
>
> David BalaÅ¾ic <xerces9@gmail.com> wrote:
> > Sun Apr 26 17:34:57 2020 daemon.debug pppd[20289]: sent [IPV6CP
> > ConfReq id=0x1 <addr fe80::d035:60ed:928e:f741>]
> > Sun Apr 26 17:35:00 2020 daemon.debug pppd[20289]: sent [IPV6CP
> > ConfReq id=0x1 <addr fe80::d035:60ed:928e:f741>]
> > Sun Apr 26 17:35:03 2020 daemon.debug pppd[20289]: sent [IPV6CP
> > ConfReq id=0x1 <addr fe80::d035:60ed:928e:f741>]
> > Sun Apr 26 17:35:06 2020 daemon.debug pppd[20289]: sent [IPV6CP
> > ConfReq id=0x1 <addr fe80::d035:60ed:928e:f741>]
> > Sun Apr 26 17:35:09 2020 daemon.warn pppd[20289]: IPV6CP: timeout
> > sending Config-Requests
>
> Could this be the reason for the hangup?
> pppd gets tired of no IPv6, decides it should hangup?

These lines are logged in the 30 seconds after the connection is
established. Later they never show up. It was like that for all
connections thus far.

> > The strange part is in the tcpdump there is a PADT sent to an
> > "unknown" MAC and my pppd responds. At least that is how I see it.
>
> > You think NOT putting the interface into promiscuous mode (done by
> > tcpdump) would prevent this?
> > Anyway, now I startted tcpdump with the -p option: tcpdump -e -v -p
> > -i eth1 vlan 3902 and pppoed
>
> It could be that promisc mode (no -p) means that the PADT makes something
> break, different than what you are investigating. -p avoid promisc mode, so
> would avoid seeing that packet.
>
> You mention in another thread that you were trying to do DHCPv6 on a
> different (non-PPPoE) interface. I don't see how that would matter unless
> the failure caused netifd to decide to retry it all.
>
> It seems that you ought to try the noipv6 option to pppd.

I removed it (from the system config, the file /etc/config/network ).
I also removed that "other interface", so there is no IPv6 stuff left.
The new command line is:
/usr/sbin/pppd nodetach ipparam wan ifname pppoe-wan lcp-echo-interval
1 lcp-echo-failure 5 lcp-echo-adaptive nodefaultroute usepeerdns
maxfail 1 user YYYYYY password XXXXX ip-up-script /lib/netifd/ppp-up
ip-down-script /lib/netifd/ppp-down mtu 1492 mru 1492 plugin
rp-pppoe.so nic-eth1.3902

For the record: The new connection with new settings was started on
Mon Apr 27 09:47:48 (UTC)