laneconfig(4)

NAME

laneconfig − LAN Emulation configuration file

SYNOPSIS

/etc/laneconfig

DESCRIPTION

The laneconfig file is a local database that associates MAC addresses with ATM addresses. The file is used by the LAN Emulation setup program, lanesetup(1M), which manages the downloading of the information found in laneconfig into the kernel. If changes are made to the laneconfig file, lanesetup(1M) must be rerun for the changes to take effect.

The format of an entry in laneconfig is:

Interface MAC-Address ATM-AddressVCFlags

Items are separated by any number of SPACE and/or TAB characters. The first item is the LAN Emulation interface on the local system which is attached to the subnet for this entry. It should be of the form “lane unit;” an example is lane0. The MAC address is the 6 byte physical MAC address; it should be specified as 6 hexadecimal bytes (2 characters) separated by one or more colons (additional colons may be used for readability, if desired). The ATM address is a 20 byte address; its format is the same colon-separated hexadecimal format used for the MAC address. The vc field specifies the virtual connection identifier (vci) for the connection to the host identified by this entry. The flag field gives information regarding the type of entry. Comment lines are allowed; they are indicated by a ‘#’ at the beginning of the line.

ATM addresses are 20 bytes. The first 13 bytes (called the prefix) are used by the switch for routing purposes; in general, they will be the same for addresses in the same subnet. The prefix is assigned by the switch and will be sent to the host when the ATM interface on the host system is configured. The predefined variable ‘prefix’ (see Variables section below) will be assigned the value received by the host from the switch at configuration time; this value may be referenced in the laneconfig file as ‘$prefix’.

The next 6 bytes (called the ESI) are used to uniquely identify a host system; in most of the examples given, the system’s hardware MAC address is used. The local MAC address may be referenced in the laneconfig file as ‘$mac’. The final byte is a selector byte that may be used by the host for internal routing of data. Use of the predefined variable ‘sel’ will guarantee that an appropriate value for the given interface will be used.

Depending on the entry type, as determined by the flags field, some or all of the fields are required. All entries must have an interface and flags field; the mac address, atm address, and vc field vary depending on the entry type. The following sections describe the use of variables in the laneconfig file, and the flag types, listing which of the mac address, atm address, and vc fields are required for that type. In all entries, an empty field should be indicated by a hyphen ‘-’.

OPTIONS

Variables

Because the prefix portion of an ATM address specifies the ATM switch, a number of hosts specified in an laneconfig file may have ATM addresses who share the same prefix. To simplify setting up the laneconfig file, one can define variables that contain part of an ATM address. A variable’s name is an identifier consisting of a collection of no more than 32 letters, digits, and underscores (‘_’). The value associated with the variable is denoted by a dollar sign (‘$’) followed immediately by the variable name.

Variables may only be used in the ATM and MAC address fields. They may not be used in any of the other fields in an entry.

Multiple variables may be concatenated to represent a single ATM address expression. A colon must be used to concatenate the variables. Thus, if one variable, v1, is set to ‘11:22’ and another, v2, is set to ‘33:44’, the sequence $v1:$v2 represents ‘11:22:33:44’. Hexadecimal numbers may also be included with variables in the expression. The expression ‘45:$v1:$v2’ would have the value ‘45:11:22:33:44’.

Variables are defined in the laneconfig file according to the following format:

set VARIABLE = EXPRESSION

where VARIABLE is the name of a variable and EXPRESSION is an expression concatenating one- or two-digit hexadecimal numbers and/or the values of variables that have been previously defined. The equal sign is optional, but the variable and expression must be separated by either whitespace (spaces or tabs), an equal sign, or both.

Several predefined variables are built in to the SunATM software. They include:

prefix the 13-byte prefix associated with the local switch.

mac the 6-byte MAC address associated with the local host or interface.

sel the default 1-byte Selector for the local interface.

macsel the concatenation of $mac:$sel.

myaddress the concatenation of $prefix:$mac:$sel, resulting in the default address for the local interface.

In most network configurations, the ATM address assigned to the local interface will be myaddress; using this variable in the ‘l’ entry makes it possible to use identical laneconfig files on all LAN Emulation clients in a given subnet.

Several rules apply to the use of variables in the laneconfig file:

Two variables cannot follow each other in an expression without an intervening colon. Thus, $v1:$v2 is legal whereas $v1$v2 is not.

Fields in each line in the laneconfig file are separated by whitespace. Therefore variables should not be separated from the rest of an ATM address with whitespace. For example, $v1: $v2 is illegal.

Once a variable is defined by a set command, it may not be redefined later in the laneconfig file.

The reserved variable names may not be set. They include ‘prefix’, ‘mac’, ‘sel’, ‘macsel’, and ‘myaddress’.

Basic Configuration Flags

l This flag identifies an entry for a local interface on a LAN Emulation client.

The ATM address is required. The MAC address should not be entered; the system will use the MAC address assigned to this physical interface. No vc should be entered either, since there will typically be multiple vcs over the local interface.

t Adds this MAC-ATM address or MAC address-vc pair to the local table.

The MAC address is required; either an ATM address or a vc field is required, depending on whether a SVC or a PVC connection is desired. If a mixture of SVC and PVC connections is desired, both an ATM address and a vc are allowed.

n Specifies the name of the Emulated LAN. Most LAN Emulation Services will fill the Emulated LAN name in in configuration and join requests from LAN Emulation Clients, but this is not always the case. If your LAN Emulation Services do not provide Emulated LAN names for client requests, you can include the name in the laneconfig file.

The Emulated LAN name should be entered in the MAC address field; the ATM address and vc fields are illegal.

The required, optional, and illegal fields for the basic flag types are summarized in the following table:

------------------------------------------------------- InterfaceMAC-AddrATM-Addr VCI FLAGS ------------------------------------------------------- required illegal required illegal l required required xor xor∗ t required Em. LAN name illegal illegal n

∗ one or the other is required; both are illegal.

Advanced Configuration Flags

The basic configuration flags are sufficient for most standard network configurations. However, since networks are rarely homogeneous, there may be cases in which, for interoperability purposes, a network must be configured with different characteristics than the defaults that are built into the SunATM adapter, or with unusual addressing schemes that require more than the basic configuration flags described above. The following flags may also be used in the laneconfig file to alter the default behavior when necessary.

c Specifies an alternate LECS address. By default, the SunATM software uses the ATM Forum well-known address. If, however, your LECS has a different address, or you wish to connect to the LECS over a PVC, you may provide the alternate ATM address or VCI in this entry. If you wish to make a PVC connection, the VCI must be 17, as required by the LAN Emulation standard.

Either an ATM address or a vc field must appear; the MAC address should not appear.

s Specifies the LES address or VCI, and instructs the system to contact the LES directly, and to use default subnet configuration information. This flag should be used if your subnet does not have an LECS. By default (no ‘s’ entry), the system first connects to the LECS, which provides the LES address and configuration information.

Either the ATM address or a vc is required. The MAC address should not appear.

The required, optional, and illegal fields for the advanced flag types are summarized in the following table:

∗ one or the other is required; both are illegal.

EXAMPLES

The following example shows a basic LAN Emulation Client’s laneconfig file. The local information is provided, as well as the addresses of a frequently used server. The use of variables is also demonstrated.

set srvr_mac = 08:00:20:01:02:03

ba0 -$myaddress-l
ba0 $srvr_mac$prefix:$srvr_mac-t

The following example shows the laneconfig file for a LAN Emulation Client whose LECS requires that the client include the Emulated LAN name in its messages.

ba1 - $myaddress-l
ba1 elan1--n

The following example shows the laneconfig file for a LAN Emulation Client whose subnet does not include an LECS.

set les_mac = 01:02:03:04:05:06

ba0 -$myaddress-l
ba0-$prefix:$les_mac-s

NOTES

Each entry should be entered on one line with no breaks or carriage returns.

SunOS 2.0 — Last change: 27 Oct 1995

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