Sun Microsystems 3U manual Configuring a Classical Internet Protocol Interface

Configuring a Classical Internet Protocol Interface

Classical Internet Protocol (Classical IP), specified by RFC 1577, is one way of supporting the TCP/IP and UDP/IP protocols in an ATM environment. In Classical IP, an ATM ARP server is used to resolve IP addresses to ATM addresses, replacing the traditional ARP protocol. In this configuration, each host must register with the ARP server when the ATM interface is brought up. For more information on the Classical IP protocols, see “Classical Internet Protocol” on page 67.

ATM ARP is used instead of the traditional ARP because ATM does not support broadcast (a network capability providing transmission from one point to all points on a network). Because Classical IP over ATM does not support broadcast, you cannot use the ypbind UNIX command with the -broadcastoption to automatically locate the NIS server (ypserver) on a Classical IP ATM subnet.

If you are planning to run NIS over your ATM network, use the ypinit -ccommand to specify the list of NIS servers (ypservers). See the ypinit(1M) man page for details of setting up the ypserver. Be sure that the IP addresses of the ypservers are listed in the /etc/hosts file.

The Routing Information Protocol (RIP) also uses the broadcast feature of IP, so it is not supported under the Classical IP environment. In the Solaris operating environment, RIP is implemented by the daemon in.routed.

If you are using Classical IP only, you must explicitly add the routes to the routers in the ATM subnet. You can also specify one router as the default router to provide connectivity outside the ATM subnet. See the route(1M) man page for information on using the route command to add specific router entries and to add a default router.

Editing the aarconfig File

The /etc/opt/SUNWconn/atm/aarconfig file is a generic file that must appear on every SunATM system that is supporting Classical IP interfaces. It allows you to specify IP to ATM address translation, permanent virtual circuits (PVCs) to destinations, and the address of the ATM ARP server. The environment allows for a mix of PVCs and switched virtual circuits (SVCs).

Each time the /etc/opt/SUNWconn/atm/aarconfig file is modified, run the ATM ARP setup program, aarsetup, which is in the /etc/opt/SUNWconn/bin directory.

44 SunATM 3U CompactPCI Adapter Installation and User’s Guide • February 2001