For the Mikrotik gurus... I've finally got fibre on.
I've set my 2011iLS-IN up so the Ethernet port on the RB connected to the ONT is 1508MTU. I've done the same for the VLAN interface.
I've set the PPPoE MTU and MRU to 1500.
It took a while to start working, but eventually everything now works and I can do a ping test at 1472 (+28 ICMP overhead) MTU without fragmentation. All looks good.
(I'm with Spark for fibre).
My question though, do I need to set the MRRU on the Mikrotik when using an MTU of 1500?
I was glad to see 1500 on PPPoE works on the Mikrotik. A mate reckoned they didn't support the 1500 MTU on PPPoE but it seems to be working fine and dandy.
Do I need to set the Ethernet MTU to 1512 though to account for the VLAN tagging?