OPNsense Forum

English Forums => 24.7, 24.10 Legacy Series => Topic started by: IamNotABot! on December 15, 2024, 10:14:05 PM

Title: ICMP stops working after one-to-one NAT
Post by: IamNotABot! on December 15, 2024, 10:14:05 PM
My WAN port address is 10.100.11.130
My LAN network is 192.168.12.1/24
I have a LAN port device with a static IP of 192.168.12.25
I created a Virtual IP of 10.100.11.131
At this point I can ping 10.100.11.130 and 10.100.11.131
If I NAT 10.100.11.131 to 192.168.12.25, ICMP stops working to 10.100.11.131
I can still ping 10.100.11.130
The device with 192.168.12.25 can ping out to 10.100.11.1 (external gateway), 8.8.8.8 and google.com
I can VNC from the 10.100.11.1 network to 10.100.11.131 which NATs to 192.168.12.25 device

What am I missing in the rules to get ICMP working again to 10.100.11.131?
I've tried creating rules to specifically allow ICMP to 10.100.11.131 with no success.


Title: Re: ICMP stops working after one-to-one NAT
Post by: viragomann on December 15, 2024, 11:29:28 PM
Quote from: IamNotABot! on December 15, 2024, 10:14:05 PMIf I NAT 10.100.11.131 to 192.168.12.25, ICMP stops working to 10.100.11.131
So with this NAT rule, any packet goes to the target device, presumed the firewall rules allows it.

Now, the access is probably blocked by the destination device itself.
Blocking access from OUTSIDE of the own subnet is the default configuration of most system firewalls. So maybe you have to allow the access on 192.168.12.25.