VDSL SFP Bridge Modem


Would you mind to elaborate/share on setting this up? There are few users that would be interested to know how to get DSLMonitor working. User experience - ALLNET ALL4781-VDSL2-SFP / Switch Modul (Mini-GBIC), VDSL2.

Suppose by SFP you mean eth1? Which MAC you are sending the query frames to - eth1?


No, the SFP.
Just visualize what the SFP is, a stand alone modem connected via ethernet (imagine that you got an external DSL modem connected via ethernet to an copper/rj45 SFP) – just all squashed into the shape of an SFP.
Therefore to address the modem inside the SFP you need to send the packets to the MAC address of the modem (MAC printed on the SFP). If you would send it to the MAC of eth1 you would address the Omnia.

I’ll put my example config into the user experience thread.


Sure, it just that the router has no awareness of the modem’s MAC and earlier tests did not yield any result.

Looking forward to your sample config, particularly about bridging eth1 with the vlan.


It is how a normal switch/bridge (like desktop switch) works and is mirrored by an Linux software bridge.
If it hasn’t knowledge of an MAC then it floods it to all ports. It learns MAC to port relations by watching source MACs of packets which arrive.
The standard linux bridge is pretty poor in functionality (esp. in the diagnostics department).
However with a recent brctl you can get the forwarding table including learned MACs via "brctl showmacs ", e.g.

root@dtank0:~# brctl showmacs wsbr0
port no mac addr                is local?       ageing timer
  1     00:16:3e:7c:c4:1a       no                32.21
  1     0c:c4:7a:c6:e4:17       yes                0.00
  1     0c:c4:7a:c6:e4:17       yes                0.00
  2     12:04:0a:7c:c4:1b       no                 0.00
  1     3c:a8:2a:9f:d1:54       no                 2.04
  1     e4:8d:8c:7e:4b:30       no                 0.46
  2     fe:04:0a:7c:c4:1b       yes                0.00
  2     fe:04:0a:7c:c4:1b       yes                0.00

The ones with an ageing timer are learned ones.
Note that older brctl versions as well as the busybox based one doesn’t include the showmacs option.


Thanks for the notice, Andre, I went with a different solution since but remain interested. I’ll keep an eye on this and the ‘Allnet experience’ thread others have mentioned here.


I just wanted to let people here know there’s a similar discussion happening on OpenWRT’s forum:

I’m curious to see if the conclusions are similar…