In Oracle Solaris, a system with more than one interface can be configured as a multihomed host. The interfaces of a multihomed host connect to different subnets, either on different physical networks or on the same physical network. For step-by-step instructions on creating a multihomed host, see How to Create a Multihomed Host.
A multihomed host can have some of its interfaces connected to the same subnet. You must configure such interfaces into an IPMP group. For more information about IPMP, see Chapter 2, About IPMP Administration in Administering TCP/IP Networks, IPMP, and IP Tunnels in Oracle Solaris 11.3.
A multihomed host does not forward IP packets, but you can configure a multihomed host to run routing protocols. You typically configure the following types of systems as multihomed hosts:
NFS servers, particularly those servers that function as large data centers, can be attached to more than one network to share files among a large pool of users. These servers do not need to maintain routing tables.
Database servers can have multiple network interfaces that provide resources to a large pool of users, just like NFS servers.
Firewall gateways are systems that provide the connection between a company's network and public networks such as the Internet. Administrators set up firewalls as a security measure. When configured as a firewall, the host does not pass packets between the networks that are attached to the host's interfaces. However, the host can still provide standard TCP/IP services such as ssh to authorized users.