|C H A P T E R 2|
Configuring the SunATM Interfaces
The SunATM configuration program, atmadmin, is an interactive command-line interface. The program contains a hierarchy of menus, which divide the configuration into six main parameter groups: system, physical layer, signalling, ILMI, Classical IP, and LAN Emulation. All but the system parameter group are specific to individual SunATM interfaces, so you must configure the parameters in these groups separately for each interface.
If you prefer, you can enter and change the SunATM configuration information by editing the SunATM configuration files directly. See Chapter 3.
Note - See the Glossary for descriptions of the ATM and SunATM terms used in this chapter. Chapter 3," and Chapter 5," also provide more information about ATM protocols and the SunATM implementation of these protocols.
The atmadmin program is installed with the SUNWatm software package in the
/etc/opt/SUNWconn/bin directory. The program must be run as superuser. It can be run in any local or remote shell on the SunATM system.
After you start the atmadmin configuration program, you see the atmadmin Main Menu. From this menu you can either go to the system parameter group menu (see System Parameter Group Menu), or you can enter the SunATM interface you want to configure. The following screen example is from a system with one interface named ba0.
After selecting an interface, you will then see the Interface Configuration menu (see Interface Configuration Menu).
TABLE 2-1 lists the basic commands that let you navigate through the menu hierarchy.
You can configure your SunATM system as an ATM SNMP agent. The SunATM SNMP daemon, atmsnmpd, always runs on an ATM host. If you do not run your system as an SNMP agent, the daemon does not bind to a UDP port.
Once you select a SunATM interface, you will see the atmadmin Interface Configuration menu. From this menu you can proceed to the interface parameter group sub-menus, which are described in atmadmin Parameter Groups. You can use these sub-menus to change the SunATM interface configuration parameters.
The atmadmin program first attempts to read the current configuration information from the /etc/opt/SUNWconn/atm/atmconfig,
/etc/opt/SUNWconn/atm/aarconfig, and /etc/opt/SUNWconn/atm/laneconfig files. If no configuration information is found, or if the files do not exist, the default values listed in are applied to the installed interfaces.
Caution - When saving configuration information, atmadmin overwrites the existing SunATM configuration files in the /etc/opt/SUNWconn/atm directory. Therefore, any comments or other changes you manually made to the files will be lost.
The atmadmin configuration program contains a series of menus where you can input or alter the configuration of specific SunATM software parameters. These menus, or parameter groups, are described in this chapter:
TABLE 2-2 summarizes the configurable parameters in each parameter group. Although the parameter list appears rather lengthy, you only need to use the default values for most standard configurations. The large number of parameters offer the flexibility to support special case configurations, and to allow interoperability with equipment from other vendors.
The framing interface defines the encapsulation method used for ATM cells as they are sent onto the wire. The default framing interface is SONET, but the SunATM software also supports the SDH interface. Your switch product information should indicate whether your switch uses either the SONET or the SDH interface. If the switch uses the SDH interface, you will need to select SDH from the physical parameter group menu.
The SunATM software supports three versions of the ATM Forum's User Network Interface (UNI) Specification: versions 3.0, 3.1, and 4.0. You may choose not to enable signalling, but in order to support either Classical IP or LAN Emulation (or both), you must select one of the three UNI versions.
If your ATM switch does not support the Interim Local Management Interface (ILMI), you can turn off the ILMI address registration on your SunATM interface from the ILMI configuration menu. The following example shows the ILMI configuration menu.
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.
One reason ATM ARP is used instead of the traditional ARP is that 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 -broadcast UNIX command to automatically locate the NIS server (ypserver) on a Classical IP ATM subnet.
If you are planning to run NIS over your ATM network, you must specify the list of NIS servers (ypservers) using the ypinit -c command. 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.
Classical IP alone also does not support the multicast packet delivery system. If you are using Classical IP, you must explicitly add the routes to the routers in the ATM subnet. You may also specify one router as the default router to provide connectivity outside of 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.
Beginning with this release, SunATM also supports the next generation of Internet Protocol, IPv6. IPv6 ATM environments provide no support for address resolution through RFC 1577. Thus, for IPv6 environments, all destination addresses, whether PVC or SVC, must be statically configured.
The SunATM software allows you to configure your interface as a Classical IP ARP server or client, or in a standalone mode with locally configured entries. You can also use standalone mode to connect two systems back-to-back, using a Permanent Virtual Circuit (PVC). These three modes are options on the Classical IP parameter menu. IPv6 always operates in standalone mode.
Depending on the Classical IP type, different parameters willbe displayed in the Classical IP Parameter menu. The figure on the previous page shows the menu when the type is set to ARP client. The possible parameters for each type (server, client or standalone) are described in the following sections.
Regardless of the Classical IP Interface Type, you must assign an IP address and hostname to the interface. For IPv4, if you enter a hostname that appears in the
/etc/hosts file, or if NIS, NIS+, or DNS is enabled and the hostname is resolvable over it, you are not prompted to enter an IP address. Instead, the resolution is performed automatically. If the hostname cannot be resolved, you are prompted to enter an IP address. If you must enter an IP address, or if the address is only available through NIS, NIS+, or DNS, the SunATM software updates the /etc/hosts file. For IPv6, the SunATM software updates the /etc/init/ipnodes file.
A valid IP hostname is no more than 80 characters. A valid IPv4 address is a set of four decimal numbers in the range of 0 to 255, separated by dots (for example, 220.127.116.11). A valid IPv6 address is x:x:x:x:x:x.
The local ATM address is the 20-byte ATM address associated with a specific Classical IP instance. You must assign an ATM address to each Classical IP client, server, or standalone SVC. You should not assign an ATM address on standalone PVCs, such as in a back to back configuration. The following section describes ATM address formats and some of the SunATM software defined address variables.
ATM addresses, like Network Service Access Point (NSAP) addresses, are 20 octets long, with each octet made up of 1 or 2 hexadecimal digits. The ATM address is divided into three fields: the End System Identifier field, the Selector field, and the Network Prefix field. The End System Identifier (ESI) field is a unique 6 octet value, which can be the IEEE hardware MAC address conventionally associated with every network interface. The Selector field is one octet long. The 13 octets that make up the rest of the ATM address are called the Network Prefix. This field should be derived from the ATM switch fabric to which the interface is connected. Every ATM switch fabric is configured with a 13 octet prefix.
To simplify references to ATM addresses in the SunATM software, several system-defined variables are built into the software. Variables are referenced with the $ operator, as in UNIX shell scripts. TABLE 2-3 summarizes the system-defined SunATM address variables.
ATM addresses are represented by 20 colon-separated octets, with each octet made up of 1 or 2 hexadecimal digits. You can combine variables representing portions of an ATM address with other variables and/or octets to make up a complete address. For example, $prefix:aa:bb:cc:dd:ee:ff:$sel represents a valid ATM address.
The Permanent Virtual Circuit parameter applies only to standalone configurations, including IPv4 and IPv6. This option is available when you add a Virtual Circuit from the standalone mode. It identifies the PVC that will be used to communicate between the two systems connected either back to back or to ports on switches. Both systems must use the same PVC value. The PVC parameter must be an integer (not hexadecimal) between 32 and 1023.
The ATM destination address parameter configures a static SVC. This parameter applies only to IPv4 and IPv6 standalone configurations. It is available when you add a Virtual Circuit from the Standalone menu. For SVC operation over IPv6, all addresses must be statically configured. See ATM Address Formats and Variables for more information.
LAN Emulation, standardized by the ATM Forum's LAN Emulation 1.0 specification, is another way of providing TCP/IP and UDP/IP support over an ATM interface. Address resolution information is provided by a series of LAN Emulation services. When a LAN Emulation interface is brought up, it must register with these LAN Emulation services (known as "joining the LAN"). This registration process and the address resolution process are described in LAN Emulation.
Unlike Classical IP, the LAN Emulation protocol provides a broadcast service to the upper layer protocols. Therefore, the multicast and RIP limitations described in Classical IP Parameter Group, do not affect LAN Emulation interfaces.
The SunATM software allows a single ATM interface to join up to sixteen emulated local area networks (ELANs), provided that this action is allowed by the switch and LAN Emulation (LANE) services. Each ELAN joined is represented by a unique lane instance (for example, lane0 or lane1).
Note - A requirement for supporting this feature is that the adapter card be assigned multiple MAC addresses, which the SunATM/S 2.1 and SunATM/P 3.0 adapters support. This feature does not work with the older SunATM/S 2.0 adapters. Use the atmgetmac(1M) command with the count option to find the number of MAC addresses assigned to your SunATM adapter.
After you configure LAN Emulation parameters, you are asked to choose an existing (previously configured) LAN Emulation (lane) instance or to create a new one in the LAN Emulation Instance menu. The following is an example of this menu.
If IP traffic runs over a LAN Emulation instance, assign a hostname and corresponding IP address to the instance. If you enter a hostname that appears in the /etc/init/hosts or /etc/init/ipnodes file, or if NIS, NIS+, or DNS is enabled and the hostname is resolvable over it, you are not prompted to enter an IP address. Instead, the resolution is performed automatically. If the hostname cannot be resolved, you are prompted to enter an IP address. If you must enter an IP address, or if the address is only available through NIS, NIS+, or DNS, the SunATM software updates both the /etc/init/hosts and /etc/init/ipnodes files.
A valid hostname is no more than 80 characters. A valid IP address is a set of four decimal numbers in the range of 0 to 255, separated by dots (for example, 18.104.22.168). The preferred form of an IPv6 address is x:x:x:x:x:x:x:x, where x represents the hexidecimal value of the eight 16-bit pieces of the address, for example, 1080:0:0:0:8:800:200c:417A.
The local ATM address is the 20-byte ATM address associated with this LAN Emulation instance. See ATM Address Formats and Variables for more information about ATM address formats and variables.
Each lane instance must be assigned a unique ATM address. Each SunATM 2.1 or 3.0 adapter has been assigned 16 unique MAC addresses; if you use the variable $myaddress for each lane instance, the SunATM software will automatically distribute those MAC addresses to the lane instances associated with each physical interface.
Most LAN Emulation Services include a LAN Emulation Configuration Server (LECS), which is the first server contacted when bringing up a LAN Emulation client. The LECS provides the ATM address of the LAN Emulation Server (LES), as well as other configuration information about the emulated LAN. However, some LAN Emulation services do not include an LECS, and the LES must be contacted directly. With the LECS Indicator parameter, you specify which service should be contacted first in your configuration. The possible values for this parameter are displayed as individual options on the LAN Emulation Instance menu.
By default, the SunATM software attempts to obtain the LECS address using ILMI, as specified in the LAN Emulation specification. If this is not successful, the "well-known" ATM address, also specified by the ATM Forum, is used.
If your LECS uses a different ATM address (not the well-known address), and does not make that address available via ILMI, specify it using this parameter. If applicable, any of the ATM address variables described in ATM Address Formats and Variables can be used. Use variable $prefix, in particular.
This parameter is required if the value of the LECS Indicator parameter is no_LECS. In that case, LECS is not present to provide a "well-known" address for the LES, so you must specify an ATM address. Any of the SunATM address variables described in ATM Address Formats and Variables ($prefix in particular) can be used.
If multiple Emulated LANs (ELANs) are present, you can enter a character string in the Emulated LAN Name parameter. The LAN Emulation client uses this parameter to tell the LAN Emulation services which ELAN it wishes to join. By default, if a SunATM LAN Emulation client does not specify an ELAN name, it tells the services to assign it to the default (or only) ELAN.
Note - If you have multiple LAN Emulation instances configured on a physical interface, only one instance can join the default (unspecified) ELAN. You must specify an ELAN name for all other instances.
The SunATM software supports logical interfaces in the SunATM LAN Emulation environment. Logical interfaces allow you to assign multiple IP addresses to a single LAN Emulation interface. A logical interface name consists of three parts: the device name (in the case of SunATM LAN Emulation, lane); the major number, which corresponds to the lane instance number; and the minor number, which distinguishes the logical interfaces on a single lane instance. The format of a LAN Emulation logical interface name is laneN:X, where N is the major number and X is the minor number (for example, lane0:2).
The hostname displayed in the LAN Emulation instance menu corresponds to the minor instance 0. The additional IP Address parameter indicates if any additional hostnames are assigned to the instance. Select this parameter to modify or create additional hostnames. You must enter or modify each additional IP hostname in the same manner as other IP hostname and address pairs (see ATM Address Formats and Variables for more details), and associate it with a minor number between 0 and 255.