Hello,
I have setup an IPSec VPN between Debian 11 with Libreswan and my OPNsense box.
Phase 2 config is allowing one /24 subnet to talk to a remote /24 subnet.
So far, from the Libreswan side, I can ping and RDP to remote machines attached to the OPNSense LAN just fine.
However, there's no communication from OPNSense LAN to Libreswan LAN.
Only one side of the tunnel seems to work.
Libreswan configuration :
https://hastebin.milkywan.fr/isopitazit.apache
OPNSense configuration is the following.
IKEv2 Phase 1 :


Phase 2 :


Child SA status on OPNSense :
Routing table for remote Libreswan subnet from OPNSense :

Firewall configuration for IPSec interface :

Thank you.
I have setup an IPSec VPN between Debian 11 with Libreswan and my OPNsense box.
Phase 2 config is allowing one /24 subnet to talk to a remote /24 subnet.
So far, from the Libreswan side, I can ping and RDP to remote machines attached to the OPNSense LAN just fine.
However, there's no communication from OPNSense LAN to Libreswan LAN.
Only one side of the tunnel seems to work.
Libreswan configuration :
https://hastebin.milkywan.fr/isopitazit.apache
OPNSense configuration is the following.
IKEv2 Phase 1 :


Phase 2 :


Child SA status on OPNSense :
Routing table for remote Libreswan subnet from OPNSense :

Firewall configuration for IPSec interface :

Thank you.
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