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How is IP forwarding enabled in OpenBSD PF?
IP forwarding is enabled using the sysctl (2) mechanism: NAT is specified as an optional nat-to parameter to an outbound pass rule. Often, rather than being set directly on the pass rule, a match rule is used.
How does network address translation work in OpenBSD?
Translation of ICMP packets happens in a similar fashion but without the source port modification. Since NAT is almost always used on routers and network gateways, it will probably be necessary to enable IP forwarding so that packets can travel between network interfaces on the OpenBSD machine.
How are reserved address blocks used in OpenBSD?
NAT allows an administrator to take advantage of the reserved address blocks described in RFC 1918 . Typically, the internal network will be set up to use one or more of these network blocks: An OpenBSD system doing NAT will have at least two network interfaces: one to the internet and the other for the internal network.
How is bidirectional mapping established in OpenBSD PF?
A bidirectional mapping can be established by using the binat-to parameter. A binat-to rule establishes a one-to-one mapping between an internal IP address and an external address. This can be useful, for example, to provide a web server on the internal network with its own external IP address.
What are the network names for OpenBSD PF?
The em0, em1 and athn0 interface names should be replaced as appropriate. The network configuration will use a 192.168.1.0/24 subnet for the wired clients and 192.168.2.0/24 for the wireless.
When to start dhcpd daemon in OpenBSD PF?
OpenBSD defaults to allowing only WPA2-CCMP connections in HostAP mode. If support for older (insecure) protocols is needed, they must be explicitly enabled . The dhcpd (8) daemon should be started at boot time to provide client machines with local IP addresses.