Unstable RED tunnel and lots of martian source entries in kernel.log

Question

Hello, 
 I tried to set up an UTM-to-UTM RED Firewall Server tunnel (no legacy). Sometimes I get packetloss for around 10-20 seconds. Sometimes the tunnel doesn't even come up. And I noticed lots of martian source entries in kernel.log after enabling this RED tunnel: 
 2023:01:25-14:07:21 MYUTMNAME kernel: [6324855.992965] IPv4: martian source RED-SERVER-IP from MY-WAN-IP, on dev eth5
2023:01:25-14:07:21 MYUTMNAME kernel: [6324855.993049] ll header: 00000000: ff ff ff ff ff ff XX XX XX XX XX XX XX XX ...........D.. 
 (Loglines anonymized) 
 But if I use RED Firewall Server Legacy instead of RED Firewall Server it works without any packetloss/problems. Also an IPSec tunnel works without any problems for weeks. 
 (I have multiple WAN interfaces facing the router of my company ISP) 
 What could be the problem here? 
 Regards UTMaddict

Vivek Jagad · Answer

Hey UTMaddict , Thank you for reaching out to the community, May we know the current firmware version on the UTM 9 ? 
 
 Firewall RED Server : Connects to a UTM using 9.700 or later. 
 Firewall RED Client : Connects to a UTM using 9.700 or later. 
 Firewall RED Server Legacy : Connects to a UTM using versions earlier than 9.700. 
 Firewall RED Client Legacy : Connects to a UTM using versions earlier than 9.700.