I've recently bought few wAP LTE kit (RBwAPR-2nD&R11e-LTE) to provide backup link for some remote offices and I have a problem with eoip tunnels.
We have our own LTE APN anr wAP is used as following (schematic below):
We have an APN router (mikrotik RB3011) at main office runnig OSPF and connected to the LTE operator trough fiber link. It is then connected to the LTE network via GRE tunnel.
There is an EoIP tunnel over LTE between the RB3011 and wAP, on RB3011 the EoIP interface has an IP address on wAP side EoIP interface is bridged to the ether1 and then connected to other mikrotik router which is also running OSPF.
Now, if I ping the other end of the EoIP tunnel I get responses for few minutes then no response for another few minutes and again the same. There is no pattern. Sometimes ping get trough for 1 minute sometimes for 30 minutes and then no communication for few hours. At the same time L2 and OSPF communication seems to be ok. There is active adjacency, hello packet travel across the tunnel normally and I can connect to the other end of the tunnel using mac-telnet. I can also see LLDP packet in wireshark.
The same configuration works with SXT-LTE flawlesly. I've tried latest current and bugfix firmware on wAP. APN router (RB3011) is on 6.35.4
https://imgur.com/a/MFsRdgi