Hello, guys!

I have a Mikrotik 951Ui-2nD on 3G-connection. On this router up server L2TP + IPSEC. Client on Windows 7 or Windows 10.

The problem is that if the tunnel is kept icmp-packets go through it.
Once the tunnel start walking data (load of 20% to 100%) - tunnel runs 3 minutes and off. In written logs that
Mikrotik unable to send and receive some service packets for the operation of the tunnel and that he disabled it.
The funny thing is that the ICPM could go as long as you want, but under a load of no more than 3 minutes ..
MTU put on 1200-1300-1400 - does not help. Could you help me with this?


Thank you.

P.S. In attachement debug to l2tp and ipsec.

Its works! But in SSTP mode via https.. I think provider block udp with Burst-limit or something else. GRE-traff my prov block 100%

I have observed serveral times recently that routers drop UDP "connections" when there is a lot of traffic on them.
It is looking like it is an emerging standard in lousy router development...
This will affect your L2TP/IPsec+NAT-T connections. But SSTP is over TCP and is not affected by this.