I`m stucked with a problem...
I got a RB952 Hap ACLite router used as external L2TP central point with Globally routed ISP IP Address. It uses plain L2TP with PPP accounts for users, no IPSec or any other security algos used.
Then, I got RB3011 connected as a client. It lies behind NAT`s, that`s the reason why I`m using L2TP rather all of those GRE or PPTP.
Finally, I got 2 Linux gateways as L2TP Clients, they also connected to my Hap ACLite.
Problem is, that i got OSPF configured between them, so OSPF between Mikrotiks works excellent, but that freakin FRR, just don`t want working as needed.
I`m attach Mikrotik OSPF routes screenshot. I think the issue is in missing gateway on 192.168.54.0/24 subnet which is not working as expected.
More than that, when I`m tracing IPs from 192.168.54.0/24 subnet, Mikrotik try to find it via ISP provided IP address, not the L2TP link.
And this subnet route didn`t appear in main routing table.
I wonder where is the issue, is it in Mikrotik side or on FRR side...
Question solved by switching on ROS7.