Gateway Problem

[gmathew95]

Hi there.

I'm haveing an issue with my pfSense installation.

This is my scenario:
pfSense Server has 3 NICs:
NIC 0: LAN network (192.168.100.0/24)
NIC 1: Internet Connection (ISP PPoE service)
NIC 2: Site to site MPLS link (with a Cisco Router)
pfSense Version: 2.3.1-RELEASE

(Diagram in attached)

I've setted 2 Gateways: the default gateway is for internet connection (NIC 1), the other one is just for one network reachable by the MPLS link.
My problem is that sometimes (I can not find a pattern) pfSense puts the second GW as down, and obviously I can not reach the network. However, the internet connections continues working fine. If I restart de pfSense server, all work fine again for a days or some hours, but in one moment, the GW fails again.

While the GW is down, ICMP messages to my Cisco RTR are marked as "host is down". If I disconnect the ethernet cable which connects the Cisco with the pfSense, messages changes to "destination unreachable". I tried change my NIC and the RTR but the problem persists.

Any suggestion will be welcome!

Thanks and greetings!