My ISP specifies the settings for a custom router as below:
However, when I set an MTU of 1508 to my eth1 and vlan6, and MTU & MRU & MMRU of 1500 to my PPPoE, it can't connect.
I did get it working by setting my eth1 MTU to 1500, vlan6 MTU to 1508, and unset any MTU on my PPPoE, resulting in the setup below:
I'm not sure why the settings as specified by my ISP aren't working like they should, they do work like that on an Edgerouter with OpenWrt.
I also have no clue about the Layer 2 MTU values, or what they should be, so I haven't touched them.
Any ideas how I can fix this?