Im running OPNsense on PROXMOX and when I have a WAN ips I can access the GUI, after I add LAN my connection is lost.
Any ideas?
That is why there is an "IDS" setting. Enable only that, see what gets flagged in the logs and then either disable those specific rules or remove the root cause. Obviously, when you jump directly to "IPS", some anticipated problems cause a disconnection.
I actually removed all rules of NAT and filter before adding the new LAN, which means I shouldnt have any disruption between the networks.
You cannot remove IPS rules by fiddling with NAT and firewall settings.
If you enable suricata IPS, it will detect, log and block anything suspicious. With only IDS enabled, it will detect and log only.
However, when your are locked out, you obviously cannot inspect the logs to see which suricata (i.e. not NAT/firewall) policies or rules cause the block. These are on a tab under "Intrusion Detection", not in the firewall or NAT rules.