Fedora 31, L2TP - what limits the speed?

Question

linux

Good time, dear experts!
There is Fedora, in which, using NetworkManager, an L2TP + IPsec connection to a remote MikroTik is configured. Some routes are registered. The problem is that when connected, the connection with the remote host behind the Microt does not exceed 40-50 kbit \ sec. Win, Ubuntu 19.10 and Debian 10 are fine.
I found the problem when connecting using Remmina. I also checked with ssh, winscp. The file copying speed does not exceed 5 kb/sec. By the way, ping with all this is excellent. 6 ms.
I set L2TP in Fedora like this:

code

dnf install xl2tpd
dnf install NetworkManager-l2tp
dnf install NetworkManager-l2tp-gnome

Where to dig?

UPD: I connected a tunnel from my Microt to the office one (L2TP + IPsec) to eliminate the problem on the l2tpd side in Fedor. The speed between Mikrotami is around 30Mbps, RDP from Fedora is the same as Dial-up.

UPD2: it turned out that the problem was in the PC to which it was connected remotely. everything is fine with others. like this.

Answer 1

Set the tunnel MTU value to 1390 in the L2TP server settings on Mikrotik.