Hey guys, I need your help!

I have a RB4011 running long-term 6.45.8 and bridging (L2) two LANs. No IP forwarding, no firewalling at all.
Ether1-gateway is a public ip.
Ether1 (another physical interface with name Ether1) with attached VLAN (id 1510).
L2TP BCP tunnel with activated FastPath to another Mikrotik (CHR).

Ether1-gateway FastPath is active for both tx and rx
Ether1 FastPath is active for both tx and rx
Vlan 1510 FastPath is active for rx only
L2TP FastPath is not active.

If I replace L2TP with EoIP, then FastPath becomes active for both rx and tx on Vlan 1510 and EoIP interfaces.

how your l2tp-server looks like?
i mean conf

Is Allow Fast Path enabled on the Client and Server ?

if you play with ipsec you can't use FP

I messed some more time with this trouble and I figured out that if traffic originated from Mikrotik itself (attach IP to l2tp interface and ping anything from it) then I get FP for RX on L2TP. If traffic passes thru the bridge then no FP for L2TP. I want to remind that L2TP is a part of a bridge (BCP).
My L2TP server is a plain simple config with only mRRu set for 1614 and added profile for BCP. Client config is the same. FP enabled on both sides. I don't use any encryption at all.
Does L2TP support FP for both TX and RX?
Why there is no FP when L2TP is a part of a bridge?

May be you have missing any step, when you configure l2tp. I think you need a step by step guide like [REDACTED]

May be you have missing any step, when you configure l2tp. I think you need a step by step guide like [REDACTED]

Thanks, but I don't need any step by step guides
You can replicate this issue yourself. Just add L2TP interface to a bridge (add bridge interface to ppp profile on both sides of the tunnel) and FP disappears.

if you play with ipsec you can't use FP

That is correct...
.
IPv4 fast path is automatically used if following conditions are met:

.
.
IpSec policies are not configured (ROS v6.8 )
.
.
https://wiki.mikrotik.com/wiki/Manual:Fast_Path

But you don't mention that you use IPsec, so that might not be your problem...

I don't use any encryption at all.

I've told already, that I DO NOT USE any encryption. IPSec is an encryption. I've also told above, if you don't use L2TP as BCP bridge interface, then FastPath for RX side actually works.
Please read carefully before reply.

Does L2TP support FP for both TX and RX?
Why there is no FP when L2TP is a part of a bridge?

Could anyone tell me do they have FastPath on regular L2TP interface for both TX and RX?

Please read carefully before reply.

Chill out @acidsas, people here dedicate some of their time to help you...