VDSL PPPoE interface down after config restore

Hi all,


I'm currently offline @home and can't get the main reason. Hope s/o can help me:

I decided to change the UTM's (9.605-1, home license) hostname and did this by creating and importing a backup without unique data. After restart and reconfiguring hostname and admin account the WAN interface eth1 (PPPoE, settings were kept) has state offline and link offline.

I've had a look into the PPPoE log. There the connection has been successfully established. From the shell I can even ping the public IP. A bit weired is: Restarting the device without a connection to the modem it still shows up with IP but Default GW and IPv6 DefGW from the provider.

So I changed the interface to ethernet -> link states up immediately (!) and rebooted. After reboot changed back to PPPoE and Link status is Down again.

Additionally I tried following to get the interface up again:

- changed interface port on Modem (Zyxel Speedlink 5501)  -> PPPoE log seems ok, modem link states up, utm still down.
- changed MAC of eth1 PPPoE adapter -> PPPoE log seems ok, restarting connection with new mac -> modem link states up, utm still down.
- changed nic settings (duplex, speed,...) -> modem link states up, utm still down. 
- did a hardware reset of the modem / config backup to router and again back to modem only -> modem link states up, utm still down. 

I remember I've had that issues when using a cable connection. That was always resolved by a modem reset. Now I don't know how to proceed. Is there a way to fully reset every -maybe- hanging config fragments for the interface using the shell?  Or any other clue?


Really appreciate your help,


kind regards,


  • What happens if you set the NIC to a fixed speed and duplex on the 'Hardware' tab and the do the same for the Zyxel? (See #7.7 in Rulz (last updated 2019-04-17).)

    Cheers - Bob

  • In reply to BAlfson:

    Thnx Bob,

    'til now I tried that only on UTM side. Unfortunately as I'm running the Zyxel in modem mode it's not possible to modify any settings :-(

    Yesterday I also tried simple restarting UTM a few times (of course without the expected effort). Finally, the fact that even when rebooting with the modem turned off / no cable in eth1 the UTM webgui showed up with an external DEFAULT GW made me guess there's something wrong with some config files. Logging in to UTM shell I then have had a look at the routing table.

    There was no entry with the default gw from the gui.


    To cut a long story short I did a factory reset and the line's up again. Logged in to the shell the default gw from the webgui is listed on interface ppp0.

    I suppose that for some reason some config files haven't been cleared up after the first restore. Unfortunately I switched from PPPoE to fibre @work so can't test if it's the same on licensed SG. Would be interesting to know though.