Sonicwall IPSec NAT Pass through Problem

RouterOS General
1

Trying to connect a Windows machine to a Sonicwall with IPSec through a Mikrotik running NAT and it
doesn’t connect. If we swap another router in, it connects right away. We aren’t running IPSec on the
Mikrotik and the router has no firewall rules.

Any idea what could be blocking IPSec from going through?

2

I’m able to reproduce the problem by creating an L2TP/IPSec server on a Mikrotik router as well. The server shows the connection but the packets are not getting back to the client. Any ideas?