[Help] PPPoE Incorrect Payload Length at Ether1 interface

Hi,

Been trying to get my new toy - GB750GL working over the weekend. It’s been a journey of trial and error. All good.

The ISP supports PPPoE with VLAN tag, MTU size 1500.

What I have done:

  • Setup a new VLAN interface, bond to Ether1 interface.
  • Setup a new PPPoE client (pppoe-wan) interface, bond to the new VLAN interface.
  • Set MTU across Ether1, VLAN, pppoe-wan interfaces to 1500. (and I have tried default 1480; and theoretical MTU values - all have the same problem that I am to describe)

Current RouterOS version: 6.2.

Problem: according to the traffic trace (/tool sniffer), packets are all normal @ VLAN and pppoe-wan Interface. However, packet at Ether1 interface has “Incorrect Payload Length” for the PPPoE session - and it’s consistently 4 bytes off. See example below.

Example: " Payload Length:66 [incorrect, should be 62]"

As mentioned, I have tried multiple MTU setting combinations (failed); resetting config and build from scratch (failed).

And this is really my last resort; and hopefully someone would have experienced this.

Looking forward to hearing from you.

Thanks in advanced.

P.S. I have also included the pcap traces in this threat.
trace.zip (3.37 KB)