Supporting Multiple Emulated LANs on a Single Interface

The SunATM software allows a single ATM interface to join up to sixteen emulated local area networks (ELANs), provided this is allowed by the switch and LAN Emulation (LANE) services. Each ELAN joined will be represented by a unique lane instance (for example, lane0 or lane1).

A requirement for supporting this feature is that the adapter card be assigned multiple MAC addresses, which is supported in the SunATM/S 2.1 and SunATM/P 3.0 adapters. This feature does not work with the older SunATM/S 2.0 adapters. You can find the number of MAC addresses assigned to your SunATM adapter by using the atmgetmac(1M) command with the count option.

Configure multiple ELANs by placing multiple entries in the /etc/opt/SUNWconn/atm/atmconfig and /etc/opt/SUNWconn/atm/laneconfig files. Each lane instance will have a unique hostname and IP address, ATM address, and MAC address associated with it. In addition, assign an ELAN name to the instance if any ELAN other than the default is to be joined. Provide this information, with the exception of the MAC address, which is retrieved from the board itself, in the /etc/opt/SUNWconn/atm/atmconfig and /etc/opt/SUNWconn/atm/laneconfig configuration files.

Only one signalling protocol (for example, UNI 3.0 or 3.1) and one Classical IP instance are supported per physical interface. Specify the UNI version in the first /etc/opt/SUNWconn/atm/atmconfig entry for a given interface; the Classical IP instance may be specified in any entry.

The following example shows the /etc/opt/SUNWconn/atm/atmconfig and /etc/opt/SUNWconn/atm/laneconfig files and the ifconfig -a output for a system with one SunATM interface, ba0. The interface uses UNI 3.0 for signalling, and does not run Classical IP. It joins 4 emulated LANs: the default, elan1, elan2, and elan3.

The example /etc/opt/SUNWconn/atm/atmconfig file:

Interface    UNI  CIP Hostname   LANE Instance LANE Hostname
ba0          3.0      -               0             atm0
ba0           -       -               1             atm1
ba0           -       -               2             atm2
ba0           -       -               3             atm3

The corresponding example /etc/opt/SUNWconn/atm/laneconfig file:

Interface   MAC Address/    ATM Address   VCI Flag
            ELAN Name
lane0           -            $myaddress     -    l
lane1           -            $myaddress     -    l
lane1         elan1               -         -    n
lane2           -            $myaddress     -    l
lane2         elan2               -         -    n
lane3           -            $myaddress     -    l
lane3         elan3               -         -    n

The resulting ifconfig -a output:

lo0:  flags=849<UP,LOOPBACK,RUNNING,MULTICAST> mtu 8232
      inet 127.0.0.1 netmask ff000000 
lane0:flags=863<UP,BROADCAST,NOTRAILERS,RUNNING,MULTICAST> mtu 1500
      inet 192.29.240.36 netmask ffffff00 broadcast 192.29.240.255
      ether 8:0:20:7a:37:af 
lane1:flags=863<UP,BROADCAST,NOTRAILERS,RUNNING,MULTICAST> mtu 1500
      inet 192.29.241.36 netmask ffffff00 broadcast 192.29.241.255
      ether 8:0:20:7a:37:b0 
lane2:flags=863<UP,BROADCAST,NOTRAILERS,RUNNING,MULTICAST> mtu 1500
      inet 192.29.242.36 netmask ffffff00 broadcast 192.29.242.255
      ether 8:0:20:7a:37:b1 
lane3:flags=863<UP,BROADCAST,NOTRAILERS,RUNNING,MULTICAST> mtu 1500
      inet 192.29.243.36 netmask ffffff00 broadcast 192.29.243.255
      ether 8:0:20:7a:37:b2