Cisco Catalyst 5000 Series User manual

Configuring Token Ring LAN Emulation
Last Updated: December 4, 2012
This chapter describes how to configure Token Ring LAN emulation (LANE) on the Catalyst 5000
platform. This feature is supported on the following Catalyst 5000 series ATM modules:
• ATM Dual PHY OC-12 modules (WS-X5161 and WS-X5162)
• ATM Dual OC-3 modules (WS-5167 and WS-X5168)
Support for the Token Ring LANE feature was first introduced in Cisco IOS Release 12.0(7)T.
Note Beginning with Cisco IOS Release 11.3, all commands supported on the Cisco 7500 series routers are also
supported on the Cisco 7000 series.
For a complete description of the commands in this chapter, refer to the the Cisco IOS Switching Services
Command Reference. To locate documentation of other commands that appear in this chapter, use the
command reference master index or search online.
•Finding Feature Information, page 1
•Token Ring LANE on ATM, page 2
•Network Support, page 3
•Restrictions, page 4
•Prerequisites, page 5
•Token Ring LANE Configuration Task List, page 6
•Token Ring LANE Configuration Example, page 28
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest caveats
and feature information, see Bug Search Tool and the release notes for your platform and software release.
To find information about the features documented in this module, and to see a list of the releases in which
each feature is supported, see the feature information table at the end of this module.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support.
To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Americas Headquarters:
Cisco Systems, Inc., 170 West Tasman Drive, San Jose, CA 95134-1706 USA

Token Ring LANE on ATM
LANE bridges LAN traffic across an ATM network. The Catalyst 5000 Series Token Ring LANE feature
emulates an IEEE 802.5 Token Ring LAN using ATM technology. LANE is transparent to upperlayer
protocols and applications. No changes are required to existing upperlayer protocols and applications. With
Token Ring LANE, Token Ring packets are encapsulated in the appropriate ATM cells and sent across the
ATM network. When the packets reach the other side of the ATM network, they are deencapsulated.
•Benefits, page 2
•LANE Token Ring Components, page 2
Benefits
ATM is a cell-switching and multiplexing technology that combines the benefits of circuit switching
(constant transmission delay and guaranteed capacity) with those of packet switching (flexibility and
efficiency for intermittent traffic). Like X.25 and Frame Relay, ATM defines the interface between the user
equipment (such as workstations and routers) and the network (referred to as the User-Network Interface
[UNI]).
Token Ring LANE allows Token Ring LAN users to take advantage of the benefits of ATM without
modifying end-station hardware or software. ATM uses connection-oriented service with point-to-point
signalling or multicast signalling between source and destination devices. However, Token Ring LANs use
connectionless service. Messages are broadcast to all devices on the network. With Token Ring LANE,
routers and switches emulate the connectionless service of a Token Ring LAN for the end stations.
By using Token Ring LANE, you can scale your networks to larger sizes while preserving your investment
in LAN technology.
Note The Catalyst 5000 series Cisco IOS Token Ring LANE software does not support Ethernet LANE or RFC
1483 permanent virtual connections (PVCs).
LANE Token Ring Components
LANE defines emulated LANs (ELANs). An ELAN consists of the following components:
• LANE client (LEC)--A LEC emulates a LAN interface to higher-layer protocols and applications. It
forwards data to other LANE components and performs LANE address resolution functions. Each
LEC is a member of only one ELAN. However, a switch or a Catalyst ATM module can include LECs
for multiple ELANs; there is one LEC for each ELAN of which it is a member.
If a switch has LECs for multiple ELANs, the switch can route traffic between ELANs.
• LANE server (LES)--The LES is the control center for an ELAN. It provides joining, address
resolution, and address registration services to the LECs in that ELAN. LECs can register destination
unicast and multicast MAC address with the LES. The LES also handles LANE Address Resolution
Protocol (LE_ARP) requests and responses and maintains a list of route descriptors that is used to
support source-route bridging (SRB) over ELANs. The route descriptors are used to determine the
ATM address of the next hop in the frame’s routing information field (RIF).
There is one LES per ELAN.
Benefits
Token Ring LANE on ATM
2

• LANE broadcast and unknown server (BUS)--The BUS floods unknown destination traffic and
forwards multicast and broadcast traffic to LECs within an ELAN.
One combined LES and BUS is required for each ELAN.
• LANE Configuration Server (LECS)--The LECS contains the database that determines which ELAN a
device belongs to (each LECS can have a different database). Each LEC contacts the LECS once to
determine which ELAN it should join. The LECS returns the ATM address of the LES for that ELAN.
One LECS is required for each ATM LANE switch cloud.
The LECS database can have the following types of entries:
•◦ELAN name, ATM address of LES pairs
◦ELAN name and the ring number of the ELAN (local-seg-id)
◦LEC MAC address, ELAN name pairs
◦LEC ATM template, ELAN name pairs
◦Default ELAN name
Note An ELAN name must be unique on an interface. If two interfaces participate in LANE, the second interface
may be in a different switch cloud.
The server assigns individual LECs to particular ELANs by directing them to the LES for the ELAN. The
LECS maintains a database of LEC and server ATM or MAC addresses and their ELANs. A LECS can
serve multiple ELANs.
• Fast Simple Server Redundancy Protocol (FSSRP)--Token Ring LANE relies on three servers: LECS,
LES, and BUS. If any one of these servers fails, the ELAN cannot fully function.
Cisco has developed a fault tolerant mechanism known as Simple Server Redundancy Protocol (SSRP) that
eliminates these single points of failure. Although there is only one LES per ELAN, SSRP allows you to
configure redundant servers. You can configure servers to act as backup servers that become active if a
master server fails. The priority levels for the servers determine which servers have precedence.
FSSRP is an enhancement to the SSRP. With FSSRP, LECs no longer need to go down whenever there is a
change in the master LES. This uninterrupted service is achieved by connecting the LECs simultaneously
to more than one LES/BUS (up to four) so that if the master LES goes down, the backup LESs are
immediately available. With the basic SSRP, the LEC must go down and completely recycle before coming
back up. This operation is accomplished by keeping the control connections open to all of the active LESs
and BUSs in the ELAN. Although this method uses more virtual circuits (VCs), the main benefits are the
transparency and speed in the switchover.
Note ELAN components coexist on one or more Cisco routers or Catalyst switches that contain an ATM module.
On Cisco routers or Catalyst switches the LES and the BUS are combined into a single entity.
Network Support
The Token Ring LANE on the Catalyst 5000 series ATM module feature supports the following
networking features:
• LAN switching between ELANs and between a Token Ring ELAN and a legacy LAN
LANE Token Ring Components
Network Support
3

• Two-port and multiport SRB between ELANs and between ELANs and a Token Ring LAN
• SRB, source-route transparent bridging (SRT), and source-route switching
The Cisco implementation of LANE over IEEE 802.5 uses existing terminology and configuration options
for Token Rings and provides for the IEEE 802.5 transport of Token Ring frames across an ATM switching
fabric.
Restrictions
Before you implement Token Ring LANE, be aware of the following restrictions:
Caution While VLAN Trunking Protocol (VTP) Version 2 must be enabled on a Catalyst 5000 for Token Ring to
function, do not use VTP to distribute VLAN configuration information between the switches. Configure
the switches to operate in VTP transparent mode and manually configure the VLANs on each switch.
• If you plan to run both Ethernet and Token Ring LANE, the Ethernet LANE software and the Token
Ring LANE software must be run on separate ATM modules.
• All ATM switches have identical lists of the global LECS addresses with the identical priorities.
• Ensure that the spanning-tree port cost and priority for the ATM port are configured so that the ATM
port is the preferred path (the lowest port cost with the highest priority).
• Only one LEC can be defined for each subinterface. Up to 256 subinterfaces per ATM module can be
configured.
• Do not create more than one LEC for each Token Ring Bridge Relay Function (TrBRF) in each ATM
module.
While you can have only one LEC for each TrBRF in each module, you can have more than one module
installed. These additional modules allow you to have more than one LEC per TrBRF, which means the
module can participate in more than one ELAN. The ELANs, however, cannot be parallel or the Spanning-
Tree Protocol will block one of the connections.
Note Configuring more than one LEC for a TrBRF on a single ATM module will adversely affect frame
forwarding.
• Do not configure parallel ELANs within a TrBRF (parallel ELANs are those ELANs that form a loop
between switches).
• Do not create more than one LEC for each Token Ring Concentrator Relay Function (TrCRF) per
ATM module.
• Ensure that all-routes explorer (ARE) reduction is enabled (using the set tokenring reduction enable
command) on the Token Ring module.
• The number of LESs that can be defined per ELAN is unlimited; however, only one LES per ELAN
can be active at a time.
• When a LECS switchover occurs, no previously joined clients are affected.
• In a LES/BUS switchover, there is a momentary loss of clients until all clients are transferred to the
new LES/BUS.
• LECSs automatically come up as masters until a higher-level LECS takes priority.
• Using FSSRP, you can configure redundant LESs or BUSs and LECSs to reduce the possibility of a
server failure resulting in loss of communication on the LANE network. With redundant LES/BUSs
LANE Token Ring Components
Restrictions
4

and LECSs, LANE components can switch automatically to the backup LES/BUS or LECS if the
primary server fails. For specific information on how to configure FSSRP, refer to the Configuring
Fast SSRP for Redundant LANE Services, page 24 section.
Note FSSRP works only with LECS and LES/BUS combinations on Cisco devices. Third-party LANE
components interoperate with the LECS and LES/BUS functions of Cisco devices but cannot take
advantage of the redundancy features. Additionally, FSSRP-unaware LECs on Cisco equipment cannot
take advantage of FSSRP LES/BUS redundancy.
• When a higher-priority LES comes online, it bumps the current LES off the same ELAN. For a short
time after power on, some clients might change from one LES to another, depending upon the order of
the LESs coming up.
• If no LES/BUS pair is up or connected to the master LECS, and more than one LES/BUS is defined
for an ELAN, the LECS rejects any configuration request for that specific ELAN.
• Changes made to the list of LECS addresses on ATM switches can take up to 1 minute to propagate
through the network. Changes made to the LECS database regarding LES addresses take effect almost
immediately.
• If no LECS is operational or reachable, the "well-known" LECS address defined by the ATM Forum is
used.
• The LECS to be used can be overridden on any subinterface by entering the following command:
lane config-atm address
atm-address template
Note To avoid affecting the LES/BUS or LEC redundancy, do not override any LECS, LES, or BUS addresses.
• In an underlying ATM network failure, there can be multiple master LECS and multiple active LESs
or BUSs for the same ELAN, resulting in a partitioned network. Clients continue to operate normally,
but transmission between partitions of the network is not possible. The system recovers when the
network break is repaired.
Prerequisites
Token Ring LANE requires that the Catalyst 5000 series switch contain one of the following ATM
modules running ATM software Release 4.9b or later:
• ATM Dual PHY OC-12 (WS-X5161 and WS-X5162)
• ATM Dual PHY OC-3 (WS-X5167 and WS-X5168)
These ATM modules provide an ATM network interface for the Catalyst 5000 series switch. Network
interfaces reside on modular interface processors, which provide a direct connection between the high-
speed synergy backplane and the external networks. The maximum number of ATM modules that the
switch supports depends on the bandwidth configured.
The Catalyst 5000 series Token Ring LANE software also requires the Catalyst 5000 series supervisor
engine software Release 4.3(1a) or later and one of the following switches:
• Cisco LightStream 1010 with Cisco IOS Release 12.0(1)W5 or later (recommended)
LANE Token Ring Components
Prerequisites
5

• Any ATM switch with UNI 3.0/3.1 and Interim Local Management Interface (ILMI) support for
communicating the LECS address
Note If you plan to run both Ethernet and Token Ring LANE, the Ethernet LANE software and the Token Ring
LANE software must be run on separate ATM modules.
Token Ring LANE Configuration Task List
Note There can be multiple LECSs in an ATM cloud.
Before configuring Token Ring LANE, you must first open a session with the ATM module in the Catalyst
5000 series switch by entering the session line configuration command from the supervisor Console>
prompt. After opening the session, you see the ATM> prompt. You only have direct access to the ATM
module with which you have established a session.
Note The ATM module uses a subset of the Cisco IOS software. Generally, the Cisco IOS software works the
same on the ATM module as it does on routers. After configuring the ATM module, you are ready to
implement LANE.
•Opening a Session from the Switch to the ATM Module, page 6
•Creating a LANE Plan and Worksheet, page 7
•Configuring the ATM Module from the Terminal, page 8
•Configuring the ATM Module from NVRAM, page 9
•Configuring the Prefix on the LightStream 1010 Switch, page 9
•Setting Up the Signalling PVC, page 10
•Displaying LANE Default Addresses, page 11
•Entering the LECS ATM Address on the LightStream 1010 Switch, page 11
•Configuring the LECS Database, page 12
•Binding the LECS to the ATM Interface, page 17
•Setting Up a LES BUS and a LEC, page 18
•Configuring Redundant LANE Services, page 22
•Verifying the LANE Setup, page 27
•Monitoring and Maintaining LANE Components, page 27
Opening a Session from the Switch to the ATM Module
Use the session mod_num line configuration command to open a session to the ATM module from the
Catalyst 5000 family switch in which the module is installed.
This example shows how to create a session to an ATM module installed in slot 5 of the Catalyst 5000
switch:
Console> (enable) session 5
Trying ATM-5...
Opening a Session from the Switch to the ATM Module
Token Ring LANE Configuration Task List
6

Connected to ATM-5.
Escape character is '^]'.
ATM>
After opening the session, you see the ATM> prompt. You then have direct access only to the ATM
module with which you have established a session.
Note The ATM module uses a subset of Cisco IOS software. Generally, Cisco IOS software works the same on
the ATM module as it does on routers.
To configure the ATM module, you must use the ATM configuration mode in the Cisco IOS software. To
enter global configuration mode, enter the configure EXEC command at the privileged EXEC prompt
(ATM#). You see the following message, which asks you to specify the terminal, the NVRAM, or a file
stored on a network server as the source of configuration commands:
Configuring from terminal, memory, or network [terminal]?
If you specify terminal, the run-time configuration is used. You can then save the run-time configuration
into the NVRAM. If you specify memory, the run-time configuration is updated from the NVRAM. If you
specify network, the run-time configuration is updated from a file in a server on the network.
Note You cannot configure from the network.
The ATM module accepts one configuration command per line. You can enter as many configuration
commands as you want.
You can add comments to a configuration file describing the commands you have entered. Precede a
comment with an exclamation point (!) or pound sign (#). Comments are not stored in NVRAM or in the
active copy of the configuration file. In other words, comments do not appear when you list the active
configuration with the write terminal EXEC command or list the configuration in NVRAM with the show
configuration EXEC command. Comments are stripped out of the configuration file when it is loaded to the
ATM module.
Creating a LANE Plan and Worksheet
Before you begin to configure Token Ring LANE, you must decide whether you want to set up one or
multiple ELANs. If you set up multiple ELANs, you must also decide where the servers and LECs will be
located, and whether to restrict the clients that can belong to each ELAN. Bridged ELANs are configured
just like any other LAN, in terms of commands and outputs. Once you have made those decisions, you can
configure Token Ring LANE.
Before implementing Token Ring LANE, it might help you to begin by drawing up a plan and a worksheet
for your own LANE scenario, showing the following information and leaving space to note the ATM
address of each LANE component on each subinterface for each participating switch:
• Catalyst 5000 series switch interface where the LECS will be located.
• Catalyst 5000 series switch interface and subinterface where the LES/BUS for each ELAN will be
located. For fault-tolerant operation, multiple servers can be on each ELAN.
• Catalyst 5000 series switch ATM modules, subinterfaces, and VLANs where the LECs for each ELAN
will be located.
• Name of the default ELAN (optional). The default Token Ring ELAN is the same as the default
TrCRF (1003). You can use the default Token Ring ELAN (trcrf-default) or configure a new one.
Creating a LANE Plan and Worksheet
Token Ring LANE Configuration Task List
7

• Names of the ELANs that will have unrestricted membership.
• Names of the ELANs that will have restricted membership.
• Local segment ID for the ELAN. The local segment ID must be identical to the ring number of the
TrCRF.
Note The last three items in the list above are important because they determine how you set up each ELAN in
the LECS database.
•Default LANE Configuration, page 8
Default LANE Configuration
The table below shows the default LANE configuration.
Table 1 Default LANE Configuration
Feature Default Value
LANE components No LECS database is configured.
No LES/BUS is configured.
No LECs are configured.
PVCs ILMI and signalling PVCs are set up.
Preferred PHY (Dual PHY modules only) PHY A
Output throttling Disabled
ILMI keepalives Disabled
UNI version Autonegotiate (reverts to UNI 3.0 if autonegotiation
fails)
VTP Disabled
Configuring the ATM Module from the Terminal
To configure the ATM module from the terminal, use the following commands beginning in privileged
EXEC mode:
SUMMARY STEPS
1. ATM# configure terminal
2. ATM(config)# interface atm>elanname
3. ATM(config-if)# lane client tokenring>elanname
4. ATM(config-if)# Ctrl-Z
5. ATM(config)# write memory
Configuring the ATM Module from the Terminal
Default LANE Configuration
8

DETAILED STEPS
Command or Action Purpose
Step 1 ATM# configure terminal Selects the terminal option and enters global configuration mode.
Step 2 ATM(config)# interface atm>elanname Selects an ATM ELAN subinterface.
Step 3 ATM(config-if)# lane client tokenring>elanname Identifies the ELAN attached to this subinterface as a Token Ring
ELAN.
Step 4 ATM(config-if)# Ctrl-Z Exits global configuration mode.
Step 5 ATM(config)# write memory Saves the configuration file modifications to NVRAM.
In the following example, the ATM module is configured from the terminal. The interface atm 0 interface
configuration command designates that ATM interface 0 is to be configured. The lane client tokenring
command links TrCRF 10 to the ELAN named trcrf-10. The Ctrl-Z command quits configuration mode.
The write memory command loads the configuration changes into NVRAM on the ATM module.
ATM# configure terminal
ATM (config)# interface atm 0
ATM (config-subif)# lane client tokenring 10 trcrf-10
ATM (config-subif)# Ctrl-Z
ATM# write memory
NVRAM stores the current configuration information in text format as configuration commands, recording
only nondefault settings. The ATM module software performs a memory checksum to guard against
corrupted data.
As part of its startup sequence, the ATM module startup software always checks for configuration
information in NVRAM. If NVRAM holds valid configuration commands, the ATM module executes the
commands automatically at startup. If the ATM module detects a problem with its NVRAM or the
configuration it contains, the module goes into default configuration. Problems can include a bad checksum
for the information in NVRAM or the absence of critical configuration information.
Configuring the ATM Module from NVRAM
To configure the ATM module from NVRAM, reexecute the configuration commands in privileged EXEC
mode:
Command Purpose
ATM(config)# configure memory Configures the ATM module from NVRAM.
Configuring the Prefix on the LightStream 1010 Switch
Before you configure LANE components on a Catalyst 5000 series switch ATM module, you must
configure the Cisco LightStream 1010 switch with the ATM address prefix to be used by all LANE
components in the switch cloud.
Configuring the ATM Module from NVRAM
Default LANE Configuration
9

Note On the Cisco LightStream 1010 switch, the ATM address prefix is called the node ID. Prefixes must be 26
digits long. If you provide fewer than 26 digits, zeros are added to the right of the specified value to fill it to
26 digits. LANE prefixes must start with 39 or 47.
Note If you do not save the configured value permanently, it will be lost when the switch is reset or powered off.
To display the current prefix on the Cisco LightStream 1010 switch, use the show network EXEC
command.
To set the ATM address prefix, use the following commands on the Cisco LightStream 1010 switch
beginning in global configuration mode:
SUMMARY STEPS
1. Switch(config)# atm address {atm_address | prefix... }
2. Switch(config)# exit
3. Switch# copy running-config startup-config
DETAILED STEPS
Command or Action Purpose
Step 1 Switch(config)# atm address {atm_address | prefix... } Sets the local node ID (prefix of the ATM address).
Step 2 Switch(config)# exit Exits global configuration mode.
Step 3 Switch# copy running-config startup-config Saves the configuration values permanently.
Setting Up the Signalling PVC
You must set up the signalling PVC and the PVC that will communicate with the ILMI on the major ATM
interface of any Catalyst 5000 series switch that participates in LANE. Complete this task only once for a
major interface. You need not repeat this task on the same interface even though you might configure LESs
and clients on several of its subinterfaces.
To set up these PVCs, use the following commands beginning in global configuration mode:
SUMMARY STEPS
1. ATM(config)# interface atmslot/port
2. ATM(config)# atm pvcvcd vpi vci qsaal
3. ATM(config)# atm pvcvcd vpi vciilmi
DETAILED STEPS
Command or Action Purpose
Step 1 ATM(config)# interface atmslot/
port Specifies the major ATM interface and enters interface configuration mode.
Setting Up the Signalling PVC
Default LANE Configuration
10

Command or Action Purpose
Step 2 ATM(config)# atm pvcvcd vpi vci
qsaal Establishes the signalling PVC that sets up and tears down switched virtual circuits
(SVCs); the vpi and vci values are usually set to 0 and 5, respectively. The vcd is the
virtual channel descriptor.
Step 3 ATM(config)# atm pvcvcd vpi
vciilmi Sets up a PVC to communicate with the ILMI; the vpi and vci values are usually set
to 0 and 16, respectively.
Displaying LANE Default Addresses
You can display the LANE default addresses to make configuration easier. Complete this task for each
Catalyst 5000 series switch ATM interface that participates in LANE. The show lane default-atm-
addressEXEC command displays default addresses for all ATM interfaces present on the switch. Write
down the displayed addresses on your LANE worksheet.
To display the default LANE addresses, use the following command in global configuration mode:
Command Purpose
ATM# show lane default-atm-addresses
[interface atm number
[.subinterface-number
]]
Displays the LANE default addresses.
Entering the LECS ATM Address on the LightStream 1010 Switch
You must enter the LECS ATM address into each ATM switch (such as a Cisco LightStream 1010 ATM
switch) connected to an ATM module in your LANE network and save the address permanently so that the
value will not be lost when the switch is reset or powered off. Programming the LECS addresses allows the
LESs and LECs to determine the LECS addresses dynamically through ILMI.
To enter a LECS ATM address into a LightStream 1010 switch and save it there permanently, use the
following commands on the Cisco LightStream 1010 switch beginning in global configuration mode:
SUMMARY STEPS
1. Switch(config)# atm lecs-address-default address1 [address2... ]
2. Router(config)# exit
3. Switch# copy running-config startup-config
DETAILED STEPS
Command or Action Purpose
Step 1 Switch(config)# atm lecs-address-default
address1 [address2... ] Specifies the LECS’s ATM address for the entire switch. Use the
addresses from your LANE worksheet and specify the full 40-digit
ATM address.
Step 2 Router(config)# exit Exits global configuration mode.
Displaying LANE Default Addresses
Default LANE Configuration
11

Command or Action Purpose
Step 3 Switch# copy running-config startup-config Saves the configuration value permanently.
Configuring the LECS Database
The LECS database contains LANE configuration information, including ELAN name-to-LES/BUS ATM
address mappings, LEC address-to-ELAN name mappings, and the name of the default ELAN, if specified.
You must configure at least one LECS database in the LANE network.
When configuring the LECS database, remember the following guidelines:
• You can configure redundant LECSs. Redundant LECSs should be configured on different devices in
the LANE network. If you configure more than one LECS, make sure that all databases with the same
name are identical.
• You can specify one default ELAN in the database. The LECS assigns any client that does not request
a specific ELAN to the default ELAN.
• ELANs are either restricted or unrestricted. The LECS assigns a client to an unrestricted ELAN if the
client specifies that particular ELAN in its configuration. However, the LECS only assigns a client to a
restricted ELAN if the client is specified in the LECS’s database as belonging to that ELAN. The
default ELAN should have unrestricted membership.
• If you are configuring fault tolerance, you can have any number of servers per ELAN. Priority is
determined by entry order; the first entry has the highest priority unless you override it with the index
option.
When setting up the LECS database remember that the following are requirements when configuring LECs:
• The VLAN name must match the ELAN name.
• The ring number defined when configuring the VLAN must match the local segment ID.
The set vlan interface configuration command assumes that any ring number you enter is in hexadecimal.
Therefore, 12 is stored as the hexadecimal value 0x12. The name elan_name local-seg-id
segment_numberLANE database configuration command assumes that any value you enter for the local-
seg-id is in decimal unless you enter it explicitly in hexadecimal. For example, to define a TrCRF with a
ring number of 12 you could enter the set vlan 12 name crf12 type trcrf ring 12 parent 100 interface
configuration command or the set vlan 12 name crf12 type trcrf ring 0x12 parent 100 interface
configuration command.
When defining a corresponding LEC, you could enter the name crf12 local-seg-id 0x12 or name crf12
local-seg-id 18 LANE database configuration command because 18 is the decimal equivalent of 0x12.
To set up the database, complete the tasks in the following sections as appropriate for your ELAN plan and
scenario:
•Setting Up the Database for the Default ELAN, page 12
•Setting Up the Database for Unrestricted-Membership ELANs, page 14
•Setting Up the Database for Restricted-Membership ELANs, page 15
Setting Up the Database for the Default ELAN
When you configure a Catalyst 5000 series switch ATM module as the LECS for one default ELAN, you
need to provide the following information:
Configuring the LECS Database
Setting Up the Database for the Default ELAN
12

• A name for the database
• The ATM address of the LES for the ELAN
• A default name for the ELAN
In addition, you indicate that the LECS’s ATM address is to be computed automatically.
The default ELAN cannot be a restricted-membership ELAN. You do not need to specify the ATM or
MAC addresses of the LECs for the default ELAN.
On the Dual PHY ATM modules, you must configure redundant LESs or BUSs and a LECS, one for each
PHY.
When you configure a database with only a default unrestricted ELAN, you need not specify where the
LECs are located. That is, when you set up the LECS’s database for a single default ELAN, you need not
provide any database entries that link the ATM addresses of any clients with the ELAN name. All of the
clients are automatically assigned to a default ELAN.
Note After you configure the LECS database, you must bind the LECS database to the major ATM interface
(ATM0) on the ATM module. For information on how to bind the database to the interface, see the Binding
the LECS to the ATM Interface, page 17 section later on in this chapter.
To set up the LECS for a default ELAN, use the following commands beginning in global configuration
mode:
SUMMARY STEPS
1. ATM(config)# lane databasedatabase-name
2. ATM(lane-config-database)# nameelan -nameserver-atm-addressatm-address [index n ]
3. ATM(lane-config-database)# nameelan -namelocal-seg-idsegment-number
4. ATM(lane-config-database)# default-nameelan -name
5. ATM(lane-config-database)# exit
DETAILED STEPS
Command or Action Purpose
Step 1 ATM(config)# lane
databasedatabase-name Enters database configuration mode for the LANE database that you specify.
Step 2 ATM(lane-config-database)#
nameelan -nameserver-atm-
addressatm-address [index n ]
Binds the name of the ELAN to the ATM address of the LES in the configuration
database.
The index determines the priority. The highest priority is 0.
Enter the ATM address of the server for the specified ELAN, as noted in your LANE
worksheet and obtained in the Displaying LANE Default Addresses, page 11 section.
You can have any number of servers per ELAN for fault tolerance. Priority is determined
by entry order. The first entry has the highest priority unless you override it with the
index number.
Configuring the LECS Database
Setting Up the Database for the Default ELAN
13

Command or Action Purpose
Step 3 ATM(lane-config-database)#
nameelan -namelocal-seg-
idsegment-number
Assigns a segment number to the emulated Token Ring LAN in the configuration
database.
The segment number you specify for the local-seg-id keyword must remain the same for
each entry you add and it must also be identical to the ring number of the TrCRF. The set
vlaninterface configuration command assumes that any ring number you enter is in
hexadecimal. The name elan-name local-seg-id segment-number LANE database
configuration command assumes that any value you enter for the local-seg-id keyword is
in decimal unless you enter it explicitly in hexadecimal.
Step 4 ATM(lane-config-database)#
default-nameelan -name Provides a default name for the ELAN in the configuration database.
If you are setting up only a default ELAN, the elan-name argument in Step 2 and Step 3
is the same as the default ELAN name you provide in Step 4.
Step 5 ATM(lane-config-database)#
exit Exits from database configuration mode and returns to global configuration mode.
Setting Up the Database for Unrestricted-Membership ELANs
When you configure unrestricted-membership ELANs in the LECS database, you create database entries
that link the name of each ELAN to the ATM address of its LES/BUS.
However, you may choose not to specify where the LECs are located. That is, when you set up the LECS’s
database, you do not have to provide any database entries that link the ATM addresses or MAC addresses
of any clients with the ELAN name. The LECS assigns the clients to the ELANs specified in the client’s
configurations.
Note In the steps listed in the task table, enter the ATM address of the server for the specified ELAN, as noted in
your LANE worksheet and obtained in the Displaying LANE Default Addresses, page 11 section earlier in
this chapter.
To configure unrestricted-membership ELANs in the LECS database, use the following commands
beginning in global configuration mode:
SUMMARY STEPS
1. ATM(config)# lane databasedatabase-name
2. ATM(lane-config-database)# nameelan-name1server-atm-addressatm-address [index n ]
3. ATM(lane-config-database)# nameelan-name2server-atm-addressatm-address [index n ]
4. ATM(lane-config-database)# nameelan -name1local-seg-idsegment-number
5. ATM(lane-config-database)# nameelan -name2local-seg-idsegment-number
6. ATM(lane-config-database)# default-nameelan-name
7. ATM(lane-config-database)# exit
Configuring the LECS Database
Setting Up the Database for Unrestricted-Membership ELANs
14

DETAILED STEPS
Command or Action Purpose
Step 1 ATM(config)# lane
databasedatabase-name Enters database configuration mode for the LANE database that you specify.
Step 2 ATM(lane-config-database)#
nameelan-name1server-atm-
addressatm-address [index n ]
Binds the name of the first ELAN to the ATM address of the LES/BUS for that ELAN
in the configuration database.
The index determines the priority. The highest priority is 0.
Step 3 ATM(lane-config-database)#
nameelan-name2server-atm-
addressatm-address [index n ]
Binds the name of the second ELAN to the ATM address of the LES/BUS in the
configuration database.
The index determines the priority. The highest priority is 0.
Repeat this step, providing a different ELAN name and ATM address for each
additional ELAN in this switch cloud.
Step 4 ATM(lane-config-database)#
nameelan -name1local-seg-
idsegment-number
Assigns a segment number to the first emulated Token Ring LAN in the configuration
database.
The segment number you specify for local-seg-id must be identical to the ring number
of the TrCRF. The set vlancommand assumes that any ring number you enter is in
hexadecimal. The name elan-name local-seg-id segment-number command assumes
that any value you enter for the local-seg-id is in decimal unless you enter it explicitly
in hexadecimal.
Step 5 ATM(lane-config-database)#
nameelan -name2local-seg-
idsegment-number
Assigns a segment number to the second emulated Token Ring LAN in the
configuration database.
The segment number you specify for local-seg-id must be identical to the ring number
of the TrCRF. The set vlancommand assumes that any ring number you enter is in
hexadecimal. The name elan-name local-seg-id segment-number command assumes
that any value you enter for the local-seg-id is in decimal unless you enter it explicitly
in hexadecimal.
Repeat this step, providing a different ELAN name and segment number for each
additional source-route bridged ELAN in this switch cloud.
Step 6 ATM(lane-config-database)#
default-nameelan-name (Optional) Specifies a default ELAN for LECs not explicitly bound to an ELAN.
Step 7 ATM(lane-config-database)#
exit Exits database configuration mode and returns to global configuration mode.
Setting Up the Database for Restricted-Membership ELANs
When you configure restricted-membership ELANs in the LECS database, you create database entries that
link the name of each ELAN to the ATM address of its LES/BUS.
Unlike unrestricted-membership, you must also specify where the LECs are located. That is, for each
restricted-membership ELAN, you provide a database entry that explicitly links the ATM address or MAC
address of each client of that ELAN with the name of that ELAN.
Configuring the LECS Database
Setting Up the Database for Restricted-Membership ELANs
15

Those client database entries specify which clients are allowed to join the ELAN. When a client requests to
join an ELAN, the LECS consults its database and then assigns the client to the ELAN specified in the
LECS’s database.
When clients for the same restricted-membership ELAN are located in multiple switch ATM interfaces,
each client’s ATM address or MAC address must be linked explicitly with the name of the ELAN. As a
result, you must configure as many client entries as you have clients for ELANs in all the switch ATM
interfaces. Each client will have a different ATM address in the database entries.
To configure restricted-membership ELANs in the LECS database, use the following commands beginning
in global configuration mode:
SUMMARY STEPS
1. ATM(config)# lane databasedatabase-name
2. ATM(lane-config-database)# nameelan-name1server-atm-addressatm-address restricted [index n ]
3. ATM(lane-config-database)# nameelan-name2server-atm-addressatm-address restricted [index n ]
4. ATM(lane-config-database)# nameelan -name1local-seg-idsegment-number
5. ATM(lane-config-database)# nameelan -name2local-seg-idsegment-number
6. ATM(lane-config-database)# client-atm-addressatm-address-templatenameelan-name
7. ATM(lane-config-database)# exit
DETAILED STEPS
Command or Action Purpose
Step 1 ATM(config)# lane
databasedatabase-name Enters database configuration mode for the LANE database that you specify.
Step 2 ATM(lane-config-database)#
nameelan-name1server-atm-
addressatm-address restricted
[index n ]
Binds the name of the first ELAN to the ATM address of the LES/BUS for that ELAN
in the configuration database.
If you are configuring SSRP, repeat this step with the same ELAN name but with
different server ATM addresses for each additional server for the same ELAN. The
index determines the priority. The highest priority is 0.
Step 3 ATM(lane-config-database)#
nameelan-name2server-atm-
addressatm-address restricted
[index n ]
Binds the name of the second ELAN to the ATM address of the LES/BUS in the
configuration database.
The index determines the priority. The highest priority is 0.
Repeat this step, providing a different name and a different ATM address, for each
additional ELAN.
Step 4 ATM(lane-config-database)#
nameelan -name1local-seg-
idsegment-number
Assigns a segment number to the first emulated Token Ring LAN in the configuration
database.
The segment number you specify for the local-seg-id keyword must be identical to the
ring number of the TrCRF. The set vlaninterface configuration command assumes that
any ring number you enter is in hexadecimal. The name elan-name local-seg-id
segment-number LANE database configuration command assumes that any value you
enter for the local-seg-id keyword is in decimal unless you enter it explicitly in
hexadecimal.
Configuring the LECS Database
Setting Up the Database for Restricted-Membership ELANs
16

Command or Action Purpose
Step 5 ATM(lane-config-database)#
nameelan -name2local-seg-
idsegment-number
Assigns a segment number to the second emulated Token Ring LAN in the
configuration database.
The segment number you specify for the local-seg-id keyword must be identical to the
ring number of the TrCRF. The set vlaninterface configuration command assumes that
any ring number you enter is in hexadecimal. The name elan-name local-seg-id
segment-number LANE database configuration command assumes that any value you
enter for the local-seg-id keyword is in decimal unless you enter it explicitly in
hexadecimal.
Repeat this step, providing a different ELAN name and segment number for each
additional source-route bridged ELAN in this switch cloud.
Step 6 ATM(lane-config-database)#
client-atm-addressatm-
address-templatenameelan-
name
Adds a database entry associating a specific client’s ATM address with a specific
restricted-membership ELAN.
Repeat this step for each of the clients of each of the restricted-membership ELANs on
the switch cloud, in each case specifying that client’s ATM address and the name of the
ELAN with which it is linked.
Step 7 ATM(lane-config-database)#
exit Exits from database configuration mode and returns to global configuration mode.
Binding the LECS to the ATM Interface
Once you have created the database entries as appropriate to the type and the membership conditions of the
ELANs, to enable the LECS on the selected ATM interface and switch, use the following commands
beginning in global configuration mode:
SUMMARY STEPS
1. ATM(config)# interface atmnumber
2. ATM(config-if)# lane config auto-config-atm-address
3. ATM(config-if)# lane config databasedatabase-name
4. ATM(config-if)# exit
5. ATM# copy running-config startup-config
DETAILED STEPS
Command or Action Purpose
Step 1 ATM(config)# interface atmnumber If you are not currently configuring the interface, specifies the major
ATM interface where the LECS is located and enters interface
configuration mode.
Step 2 ATM(config-if)# lane config auto-config-atm-
address Specifies that the LECS’s ATM address will be computed by the
automatic method.
Step 3 ATM(config-if)# lane config
databasedatabase-name Binds the LECS’s database name to the specified major interface, and
enables the LECS.
Binding the LECS to the ATM Interface
Setting Up the Database for Restricted-Membership ELANs
17

Command or Action Purpose
Step 4 ATM(config-if)# exit Exits interface configuration mode.
Step 5 ATM# copy running-config startup-config Saves the configuration.
Setting Up a LES BUS and a LEC
For each Catalyst 5000 series switch ATM module that will participate in LANE, set up the necessary
servers and clients for each ELAN and then display and record the server and client ATM addresses. Be
sure to keep track of the switch ATM interface where the LECS will eventually be located.
If you will have only one default ELAN, you only need to set up one server. If you will have multiple
ELANs, you can set up the server for another ELAN on a different subinterface on the same interface of
this switch, or you can place it on a different switch.
When you set up a server and BUS on a switch, you can combine them with a client on the same
subinterface, a client on a different subinterface, or no client at all on the switch.
Depending on where your clients and servers are located, perform one of the following tasks for each
LANE subinterface:
•Setting Up the LES BUS for an ELAN, page 18
•Setting Up a LEC for an ELAN, page 19
•Guidelines for Setting Up a LEC, page 19
•Creating a Token Ring VLAN, page 21
•Setting Up the Token Ring VLAN on a LEC, page 22
Setting Up the LES BUS for an ELAN
To set up the LES/BUS for an ELAN, use the following commands beginning in global configuration
mode.
SUMMARY STEPS
1. ATM(config)# interface atmnumber [.subinterface-number ]
2. ATM(config-if)# lane server-bus tokenringelan-name1
3. Repeat Steps 1 and 2 for all LES/BUSs you want to configure on the ATM module.
4. ATM(config-if)# exit
5. ATM# copy running-config startup-config
DETAILED STEPS
Command or Action Purpose
Step 1 ATM(config)# interface atmnumber [.subinterface-
number ] Specifies the subinterface for the first ELAN on this switch
and enters interface configuration mode.
Step 2 ATM(config-if)# lane server-bus tokenringelan-name1 Enables a LES/BUS for the first ELAN on the subinterface
(you cannot configure more than one LES/BUS per
subinterface).
Setting Up a LES BUS and a LEC
Setting Up the LES BUS for an ELAN
18

Command or Action Purpose
Step 3 Repeat Steps 1 and 2 for all LES/BUSs you want to
configure on the ATM module.
Step 4 ATM(config-if)# exit Exits interface configuration mode.
Step 5 ATM# copy running-config startup-config Saves the configuration.
If the ELAN specified in Step 2 is intended to have restricted membership in the LECS database , carefully
consider whether or not you want to specify its name here. You will specify the name in the LECS database
when it is set up. However, if you link the client to an ELAN in this step, and through some mistake it does
not match the database entry linking the client to an ELAN, this client will not be allowed to join this
ELAN or any other.
If you do decide to include the name of the ELAN linked to the client in Step 2 and later want to associate
that client with a different ELAN, make the change in the LECS’s database before you make the change for
the client on this subinterface.
Setting Up a LEC for an ELAN
This section describes the following tasks for setting up a LEC:
•Guidelines for Setting Up a LEC, page 19
•Creating a Token Ring VLAN, page 21
•Setting Up the Token Ring VLAN on a LEC, page 22
Guidelines for Setting Up a LEC
The Catalyst 5000 series Token Ring LANE requires the following software:
• Catalyst 5000 series supervisor engine software Release 4.3(1a) and later
• ATM software Release 4.9(b) and later
• VTP Version 2
Note While VTP version 2 must be enabled on a Catalyst 5000 for Token Ring to function, do not use VTP to
distribute VLAN configuration information between the switches. Configure the switches to operate in
VTP transparent mode and manually configure the VLANs on each switch.
When you set up a LEC, follow these rules and recommendations:
• Make sure you properly configure the LECS and LES/BUS using the ATM module command-line
interface (CLI) for each VLAN before creating a LEC. VTP does not set up the LECS or LES/BUS.
• In the set vlan interface configuration command, the vlan_num argument represents the VLAN
number to configure, and the vlan_name argument is the name of the VLAN.
• The VLAN name must match the ELAN name and the ring number must match the local segment ID.
The set vlan interface configuration command assumes that any ring number you enter is in hexadecimal.
Therefore, 0x12 or 12 is stored as the hexadecimal value 0x12. The name elan_name local-seg-id
segment_numberLANE database configuration command assumes that any value you enter for the local-
seg-id keyword is in decimal unless you enter it explicitly in hexadecimal. For example, to define a TrCRF
with a ring number of 12 you could enter the set vlan 12 name crf12 type trcrf ring 12 parent 100
Setting Up a LES BUS and a LEC
Setting Up a LEC for an ELAN
19

interface configuration command or the set vlan 12 name crf12 type trcrf ring 0x12 parent 100 interface
configuration command.
When defining a corresponding LEC, you could enter name crf12 local-seg-id 0x12 or name crf12 local-
seg-id 18 because 18 is the decimal equivalent of 0x12.
• Before you can create a LEC, the TrBRF and TrCRF to which it will be associated must exist.
• Do not create more than one LEC for each TrBRF per ATM module.
While you can have only one LEC per TrBRF per module, you can have more than one module installed.
This allows you to have more than one LEC per TrBRF, which means the switch can participate in more
than one ELAN. The ELANs, however, cannot be parallel or the Spanning-Tree Protocol will block one of
the connections.
Note Configuring more than one LEC for a TrBRF on a single ATM module will adversely affect frame
forwarding.
• Ensure that all-routes explorer (ARE) reduction is enabled (using the set tokenring reduction enable
interface configuration command) on the Token Ring module.
• Do not configure parallel ELANs within a TrBRF (parallel ELANs are those ELANs that form a loop
between switches).
• Do not create more than one LEC for each TrCRF per ATM module.
A TrCRF can include only one enabled LEC from any ATM module.
An ATM module LEC is assigned to a TrCRF to provide connectivity to the ATM network. In this sense,
an ATM module is a logical port within the TrCRF. When assigning enabled LECs to TrCRFs, the enabled
LECs of any one ATM expansion module should each be assigned to different TrCRFs.
• You can change all ELAN names with the exception of VLANs 1, 1003, or 1005 whose ELAN names
must remain default, trcrf-default, and trbrf-default, respectively. You cannot override the ELAN
name for VLAN 1, 1003, or 1005 by using the name elan_name parameter. You can assign all other
VLANs any name.
When you enter the set vlan vlan_num [ name vlan_name ] interface configuration command in transparent
mode and do not specify the optional name elan_name parameter, the software uses the names in the table
below by default.
Table 2 Default VLAN ELAN Names
VLAN Number VLAN Name
1 default
2...1002 VLAN0002 through VLAN1002
1003 trcrf-default
1004 VLAN1004
1005 trbrf-default
If you currently have a different ELAN name for VLAN 1 or VLAN 1003, you must change the ELAN
name to default (for VLAN 1) or trcrf-default (for VLAN 1003) in the LECS database. The following
Setting Up a LES BUS and a LEC
Guidelines for Setting Up a LEC
20