On a network, a host can receive data packets that are destined for another host system. By enabling packet forwarding on the receiving local system, that system can forward the data packet to the destination host. This process is referred to as IP forwarding and is disabled by default in Oracle Solaris.
Packet forwarding is managed by a property that can be set on both IP interfaces and of the TCP/IP protocol. If you want to be selective about how packets are forwarded, you can enable packet forwarding on the IP interface. For example, you might have a system that has multiple NICs, where some NICs are connected to the external network, while other NICs are connected to a private network. You would therefore enable packet forwarding only on some of the interfaces, rather than on all of the interfaces.
You can also enable packet forwarding globally on the system by setting the property of the TCP/IP protocol. See Enabling Packet Forwarding Globally in Administering TCP/IP Networks, IPMP, and IP Tunnels in Oracle Solaris 11.2 for more information.
For example, you would enable packet forwarding on the IP interface as follows:
# ipadm set-ifprop -p forwarding=on -m protocol-version interface
where protocol-version is either IPv4 or IPv6. You must type the command separately for IPv4 and IPv6 packets.
The following example shows how you might enable only IPv4 packet forwarding on your system:
# ipadm show-ifprop -p forwarding net0 IFNAME PROPERTY PROTO PERM CURRENT PERSISTENT DEFAULT POSSIBLE net0 forwarding ipv4 rw off off off on,off net0 forwarding ipv6 rw off -- off on,off # ipadm set-ifprop -p forwarding=on -m ipv4 net0 # ipadm show-ifprop net0 IFNAME PROPERTY PROTO PERM CURRENT PERSISTENT DEFAULT POSSIBLE ... net0 forwarding ipv4 rw on on off on,off ...