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Cisco IOS Release 12.0 Switching Services Configuration Guide
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About the Cisco IOS Software Documentation
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Using Cisco IOS Software
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Cisco IOS Switching Services Overview
- Part 1: Cisco IOS Switching Paths
- Part 2: Cisco Express Forwarding
- Part 3: NetFlow
- Part 4: Tag Switching
- Part 5: Multilayer Switching
- Part 6: Multicast Distributed Switching
- Part 7: Virtual LANs
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Table Of Contents
Configuring Routing between VLANs with ISL Encapsulation
Overview of Inter-Switch Link Protocol
ISL Encapsulation Configuration Task List
Configure AppleTalk Routing over ISL
Define the VLAN Encapsulation Format
Configure AppleTalk on the Subinterface
Configure Banyan VINES Routing over ISL
Define the VLAN Encapsulation Format
Configure Banyan VINES on the Subinterface
Configure DECnet Routing over ISL
Define the VLAN Encapsulation Format
Configure DECnet on the Subinterface
Configure Hot Standby Router Protocol over ISL
Define the Encapsulation Format
Configure IP Routing over Token Ring ISL (TRISL)
Define the VLAN Encapsulation Format
Assign IP Address to Network Interface
Configure IPX Routing over ISL
Define the VLAN Encapsulation Format
Configure NetWare on the Subinterface
Configure IPX Routing over Token Ring ISL (TRISL)
Define the VLAN Encapsulation Format
Configure NetWare on the Subinterface
Configure VIP Distributed Switching over ISL
Enable VIP Distributed Switching
Configure ISL Encapsulation on the Subinterface
Configure XNS Routing over ISL
Define the VLAN Encapsulation Format
Configure XNS on the Subinterface
ISL Encapsulation Configuration Examples
AppleTalk Routing over ISL Configuration Examples
Banyan VINES Routing over ISL Configuration Example
DECnet Routing over ISL Configuration Example
HSRP over ISL Configuration Example
IP Routing with RIF between TrBRF VLANs
IP Routing between a TRISL VLAN and an Ethernet ISL VLAN
IPX Routing over ISL Configuration Example
Routing with RIF between a TRISL VLAN and a Token Ring Interface
VIP Distributed Switching over ISL Configuration Example
XNS Routing over ISL Configuration Example
Configuring Routing between VLANs with ISL Encapsulation
This chapter describes the Inter-Switch Link (ISL) protocol and provides guidelines for configuring ISL and Token Ring ISL (TRISL) features. For a complete description of the commands used to configure routing between VLANs using ISL encapsulation, refer to the Cisco IOS Switching Services Command Reference. To locate documentation of other commands that appear in this chapter, use the master index or search online.
Overview of Inter-Switch Link Protocol
Inter-Switch Link (ISL) is a Cisco protocol for interconnecting multiple switches and maintaining VLAN information as traffic goes between switches. ISL provides VLAN capabilities while maintaining full wire speed performance on Fast Ethernet links in full- or half-duplex mode. ISL operates in a point-to-point environment and will support up to 1000 VLANs. You can define virtually as many logical networks as are necessary for your environment.
This chapter describes how to configure routing between VLANs using ISL encapsulation.
Frame Tagging in ISL
With ISL, an Ethernet frame is encapsulated with a header that transports VLAN IDs between switches and routers. A 26-byte header that contains a 10-bit VLAN ID is prepended to the Ethernet frame.
A VLAN ID is added to the frame only when the frame is destined for a non-local network. illustrates VLAN packets traversing the shared backbone. Each VLAN packet carries the VLAN ID within the packet header.
Figure 18 VLAN packets Traversing the Shared Backbone
ISL Encapsulation Configuration Task List
You can configure routing between any number of VLANs in your network. This section documents the configuration tasks for each protocol supported with ISL encapsulation. The basic process is the same, regardless of the protocol being routed. It involves
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Enabling the protocol on the router.
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The configuration processes documented in this chapter include the following:
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Refer to the "ISL Encapsulation Configuration Examples" section at the end of this chapter for sample configurations.
Configure AppleTalk Routing over ISL
AppleTalk can be routed over virtual LAN (VLAN) subinterfaces using the ISL and IEEE 802.10 VLAN encapsulation protocols. The AppleTalk Routing over ISL and IEEE 802.10 Virtual LANs feature provides full-feature Cisco IOS software AppleTalk support on a per-VLAN basis, allowing standard AppleTalk capabilities to be configured on VLANs.
To route AppleTalk over ISL or IEEE 802.10 between VLANs, you need to customize the subinterface to create the environment in which it will be used. Perform these tasks in the order in which they appear:
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Enable AppleTalk Routing
To enable AppleTalk routing on either ISL or 802.10 interfaces, use this command in global configuration mode:
Define the VLAN Encapsulation Format
To define the VLAN encapsulation format as either ISL or 802.10, use the following commands in interface configuration mode:
Configure AppleTalk on the Subinterface
After you enable AppleTalk globally and define the encapsulation format, you need to enable it on the subinterface by specifying the cable range and naming the AppleTalk zone for each interface. To enable the AppleTalk protocol on the subinterface, use the following commands in interface configuration mode:
Configure Banyan VINES Routing over ISL
Banyan VINES can be routed over virtual LAN (VLAN) subinterfaces using the ISL encapsulation protocol. The Banyan VINES Routing over ISL Virtual LANs feature provides full-feature Cisco IOS software Banyan VINES support on a per-VLAN basis, allowing standard Banyan VINES capabilities to be configured on VLANs.
To route Banyan VINES over ISL between VLANs, you need to configure ISL encapsulation on the subinterface. Perform these tasks in the order in which they appear:
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Enable Banyan VINES Routing
To begin the VINES routing configuration, use the following command in global configuration mode:
Define the VLAN Encapsulation Format
To define the VINES routing encapsulation format, use the following commands in interface configuration mode:
Configure Banyan VINES on the Subinterface
After you enable Banyan VINES globally and define the encapsulation format, you need to enable VINES on the subinterface by specifying the VINES routing metric. To enable the Banyan VINES protocol on the subinterface, use the following command in interface configuration mode:
Configure DECnet Routing over ISL
DECnet can be routed over virtual LAN (VLAN) subinterfaces using the ISL VLAN encapsulation protocols. The DECnet Routing over ISL Virtual LANs feature provides full-feature Cisco IOS software DECnet support on a per-VLAN basis, allowing standard DECnet capabilities to be configured on VLANs.
To route DECnet over ISL VLAN you need to configure ISL encapsulation on the subinterface. Perform these tasks in the order in which they appear.
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Enable DECnet Routing
To begin the DECnet routing configuration, use the following command in global configuration mode:
Define the VLAN Encapsulation Format
To define the encapsulation format, use the following commands in interface configuration mode:
Configure DECnet on the Subinterface
To configure DECnet routing on the subinterface, use the following command in interface configuration mode:
Configure Hot Standby Router Protocol over ISL
The Hot Standby Router Protocol (HSRP) provides fault tolerance and enhanced routing performance for IP networks. HSRP allows Cisco IOS routers to monitor each other's operational status and very quickly assume packet forwarding responsibility in the event the current forwarding device in the HSRP group fails or is taken down for maintenance. The standby mechanism remains transparent to the attached hosts and can be deployed on any LAN type. With multiple hot-standby groups, routers can simultaneously provide redundant backup and perform load-sharing across different IP subnets. illustrates HSRP in use with ISL providing routing between several VLANs.
Figure 19 Hot Standby Router Protocol in VLAN Configurations
A separate HSRP group is configured for each VLAN subnet so that Cisco IOS router A can be the primary and forwarding router for VLANs 10 and 20. At the same time, it acts as backup for VLANs 30 and 40. Conversely, Router B acts as the primary and forwarding router for ISL VLANs 30 and 40, as well as the secondary and backup router for distributed VLAN subnets 10 and 20.
Running HSRP over ISL allows users to configure redundancy between multiple routers that are configured as front ends for VLAN IP subnets. By configuring HSRP over ISLs, users can eliminate situations in which a single point of failure causes traffic interruptions. This feature inherently provides some improvement in overall networking resilience by providing load balancing and redundancy capabilities between subnets and VLANs.
To configure HSRP over ISLs between VLANs, you need to create the environment in which it will be used. Perform these tasks in the order in which they appear.
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Define the Encapsulation Format
To define the encapsulation format as ISL, use the following commands in interface configuration mode:
Define the IP Address
After you have specified the encapsulation format, define the IP address over which HSRP will be routed. Use the following command in interface configuration mode:
ip address ip-address mask [secondary]
Specify the IP address for the subnet on which ISL will be used.
Enable HSRP
To enable HSRP on an interface, enable the protocol, then customize it for the interface. Use the following command in interface configuration mode:
To customize "hot standby" group attributes, use one or more of the following commands in interface configuration mode:
Configure IP Routing over Token Ring ISL (TRISL)
The IP routing over TRISL VLANs feature extends IP routing capabilities to include support for routing IP frame types in VLAN configurations.
Enable IP Routing
IP routing is automatically enabled in the Cisco IOS software for routers. To reenable IP routing if it has been disabled, use the following command in global configuration mode:
Once you have IP routing enabled on the router, you can customize the characteristics to suit your environment. If necessary, refer to the IP configuration chapters in the Network Protocols Configuration Guide, Part 1 for guidelines on configuring IP.
Define the VLAN Encapsulation Format
To define the encapsulation format as TRISL, use the following commands in interface configuration mode:
The DRiP database is automatically enabled when TRISL encapsulation is configured, and at least one TrBRF is defined, and the interface is configured for SRB or for routing with RIF.
Assign IP Address to Network Interface
An interface can have one primary IP address. To assign a primary IP address and a network mask to a network interface, use the following command in interface configuration mode:
A mask identifies the bits that denote the network number in an IP address. When you use the mask to subnet a network, the mask is then referred to as a subnet mask.
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Configure IPX Routing over ISL
The IPX Routing over ISL Virtual LANs (VLANs) feature extends Novell NetWare routing capabilities to include support for routing all standard IPX encapsulations for Ethernet frame types in VLAN configurations. Users with Novell NetWare environments can now configure any one of the four IPX Ethernet encapsulations to be routed using the Inter-Switch Link (ISL) encapsulation across VLAN boundaries. IPX encapsulation options now supported for VLAN traffic include
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NetWare users can now configure consolidated VLAN routing over a single VLAN trunking interface. With configurable Ethernet encapsulation protocols, users have the flexibility of using VLANs regardless of their NetWare Ethernet encapsulation. Configuring Novell IPX encapsulations on a per-VLAN basis facilitates migration between version of Netware. NetWare traffic can now be routed across VLAN boundaries with standard encapsulation options (arpa, sap, and snap) previously unavailable. Encapsulation types and corresponding framing types are described in the "Configuring Novell IPX" chapter of the Network Protocols Configuration Guide, Part 2.
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To configure Cisco IOS software on a router with connected VLANs to exchange different IPX framing protocols, perform these tasks in the order in which they are appear:
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Enable NetWare Routing
To enable IPX routing on ISL interfaces, use the following command in global configuration mode:
Define the VLAN Encapsulation Format
To define the encapsulation format as ISL, use the following commands in interface configuration mode:
Configure NetWare on the Subinterface
After you enable NetWare globally and define the VLAN encapsulation format, you need to enable the subinterface by specifying the NetWare network number (if necessary) and the encapsulation type. Use this command in interface configuration mode:
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Configure IPX Routing over Token Ring ISL (TRISL)
The IPX Routing over ISL VLANs feature extends Novell NetWare routing capabilities to include support for routing all standard IPX encapsulations for Ethernet frame types in VLAN configurations. Users with Novell NetWare environments can configure either SAP or SNAP encapsulations to be routed using the TRISL encapsulation across VLAN boundaries. The SAP (Novell Ethernet_802.2) IPX encapsulation is supported for VLAN traffic.
NetWare users can now configure consolidated VLAN routing over a single VLAN trunking interface. With configurable Ethernet encapsulation protocols, users have the flexibility of using VLANs regardless of their NetWare Ethernet encapsulation. Configuring Novell IPX encapsulations on a per-VLAN basis facilitates migration between versions of Netware. NetWare traffic can now be routed across VLAN boundaries with standard encapsulation options (sap and snap) previously unavailable. Encapsulation types and corresponding framing types are described in the "Configuring Novell IPX" chapter of the Network Protocols Configuration Guide, Part 2.
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To configure Cisco IOS software to exchange different IPX framing protocols on a router with connected VLANs, use these commands in the order in which they appear.
Enable NetWare Routing
To enable IPX routing on TRISL interfaces, use the following command in global configuration mode:
Define the VLAN Encapsulation Format
To define the encapsulation format as TRISL, use the following commands in interface configuration mode:
Configure NetWare on the Subinterface
After you enable NetWare globally and define the VLAN encapsulation format, you need to enable the subinterface by specifying the NetWare network number (if necessary) and the encapsulation type. Use the following command in interface configuration mode:
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Configure VIP Distributed Switching over ISL
With the introduction of the VIP Distributed ISL feature, Inter-Switch Link (ISL) encapsulated IP packets can be switched on Versatile Interface Processor (VIP) controllers installed on Cisco 7500 series routers.
The second generation Versatile Interface Processor (VIP2) provides distributed switching of IP encapsulated in ISL in VLAN configurations. Where an aggregation route performs inter-VLAN routing for multiple VLANs, traffic can be switched autonomously on-card or between cards rather than through the central Route Switch Processor (RSP). shows the VIP distributed architecture of the Cisco 7500 series router.
Figure 20 Cisco 7500 Distributed Architecture
This distributed architecture allows incremental capacity increases by installing additional VIP cards. Using VIP cards for switching the majority of IP VLAN traffic in multiprotocol environments significantly increases routing performance for the other protocols since the RSP off-loads IP and can then be dedicated to switching the non-IP protocols.
VIP distributed switching offloads switching of ISL VLAN IP traffic to the VIP card, removing involvement from the main CPU. Offloading ISL traffic to the VIP card, significantly improves networking performance. Because you can install multiple VIP cards in a router, VLAN routing capacity is increased linearly according to the number of VIP cards installed in the router.
To configure distributed switching on the VIP, you must first configure the router for IP routing. Perform these tasks in the order in which they appear:
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Enable IP Routing
To enable IP routing, use the following command in global configuration mode:
Once you have IP routing enabled on the router, you can customize the characteristics to suit your environment. Refer to the IP configuration chapters in the Network Protocols Configuration Guide, Part 1 for guidelines on configuring IP.
Enable VIP Distributed Switching
To enable VIP distributed switching, use the following commands beginning in interface configuration mode:
Configure ISL Encapsulation on the Subinterface
To configure ISL encapsulation on the subinterface, use the following commands in interface configuration mode:
Configure XNS Routing over ISL
XNS can be routed over virtual LAN (VLAN) subinterfaces using the ISL VLAN encapsulation protocol. The XNS Routing over ISL Virtual LANs feature provides full-feature Cisco IOS software XNS support on a per-VLAN basis, allowing standard XNS capabilities to be configured on VLANs.
To route XNS over ISL VLANs you need to configure ISL encapsulation on the subinterface. Perform these tasks in the order in which they appear:
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Enable XNS Routing
Begin the XNS routing configuration by using the following commands in global configuration mode:
Define the VLAN Encapsulation Format
To define the VLAN encapsulation format, use the following commands in interface configuration mode:
Configure XNS on the Subinterface
Enable XNS on the subinterface by specifying the XNS network number. Use the following command in interface configuration mode:
ISL Encapsulation Configuration Examples
This section provides configuration examples for each of the protocols described in this chapter. It includes these examples:
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AppleTalk Routing over ISL Configuration Examples
The configuration example illustrated in shows AppleTalk being routed between different ISL and IEEE 802.10 VLAN encapsulating subinterfaces.
Figure 21 Routing AppleTalk over VLAN encapsulations
As shown in , AppleTalk traffic is routed to and from switched VLAN domains 3, 4, 100, and 200 to any other AppleTalk routing interface. This example shows a sample configuration file for the Cisco 7500 series router with the commands entered to configure the network shown in .
Configuration for the Cisco 7500 Router
!appletalk routinginterface Fddi 1/0.100encapsulation sde 100appletalk cable-range 100-100 100.2appletalk zone 100!interface Fddi 1/0.200encapsulation sde 200appletalk cable-range 200-200 200.2appletalk zone 200!interface FastEthernet 2/0.3encapsulation isl 3appletalk cable-range 3-3 3.2appletalk zone 3!interface FastEthernet 2/0.4encapsulation isl 4appletalk cable-range 4-4 4.2appletalk zone 4!Banyan VINES Routing over ISL Configuration Example
To configure routing of the Banyan VINES protocol over ISL trunks, you need to define ISL as the encapsulation type. This example shows Banyan VINES configured to be routed over an ISL trunk:
Example Banyan VINES Configuration
vines routinginterface fastethernet 0.1encapsulation isl 100vines metric 2DECnet Routing over ISL Configuration Example
To configure routing the DECnet protocol over ISL trunks, you need to define ISL as the encapsulation type. This example shows DECnet configured to be routed over an ISL trunk:
Example DECnet Configuration
decnet routing 2.1interface fastethernet 1/0.1encapsulation isl 200decnet cost 4HSRP over ISL Configuration Example
The configuration example shown in shows HSRP being used on two VLAN routers sending traffic to and from ISL VLANs through a Catalyst 5000 switch. Each router forwards its own traffic and acts as a standby for the other.
Figure 22 Hot Standby Router Protocol Sample Configuration
The topology shown in illustrates a Cisco Catalyst VLAN switch supporting Fast Ethernet connections to two routers running HSRP. Both routers are configured to route HSRP over ISLs.
The standby conditions are determined by the standby commands used in the configuration. Traffic from Host 1 is forwarded through Router A. Because the priority for the group is higher, Router A is the active router for Host 1. Because the priority for the group serviced by Host 2 is higher in Router B, traffic from Host 2 is forwarded through Router B, making Router B its active router.
In the configuration shown in , if the active router becomes unavailable, the standby router assumes active status for the additional traffic and automatically routes the traffic normally handled by the router that has become unavailable.
Host 1 Configuration
interface Ethernet 1/2ip address 110.1.1.25 255.255.255.0ip route 0.0.0.0 0.0.0.0 110.1.1.101Host 2 Configuration
interface Ethernet 1/2ip address 110.1.1.27 255.255.255.0ip route 0.0.0.0 0.0.0.0 110.1.1.102!Router A Configuration
interface FastEthernet 1/1.110encapsulation isl 110ip address 110.1.1.2 255.255.255.0standby 1 ip 110.1.1.101standby 1 preemptstandby 1 priority 105standby 2 ip 110.1.1.102standby 2 preempt!end!Router B Configuration
interface FastEthernet 1/1.110encapsulation isl 110ip address 110.1.1.3 255.255.255.0standby 1 ip 110.1.1.101standby 1 preemptstandby 2 ip 110.1.1.102standby 2 preemptstandby 2 priority 105router igrp 1!network 110.1.0.0network 120.1.0.0!VLAN Switch Configuration
set vlan 110 5/4set vlan 110 5/3set trunk 2/8 110set trunk 2/9 110IP Routing with RIF between TrBRF VLANs
illustrates IP routing with RIF between two TrBRF VLANs.
Figure 23
IP Routing with RIF between TrBRF VLANs
The following is the configuration for the router:
interface FastEthernet4/0.1ip address 5.5.5.1 255.255.255.0encapsulation tr-isl trbrf-vlan 999 bridge-num 14multiring trcrf-vlan 200 ring 100multiring all!interface FastEthernet4/0.2ip address 4.4.4.1 255.255.255.0encapsulation tr-isl trbrf-vlan 998 bridge-num 13multiring trcrf-vlan 300 ring 101multiring allThe following is the configuration for the Catalyst 5000 switch with the Token Ring switch module in slot 5. In this configuration, the Token Ring port 102 is assigned with TrCRF VLAN 40 and the Token Ring port 103 is assigned with TrCRF VLAN 50.
#vtpset vtp domain trislset vtp mode serverset vtp v2 enable#dripset set tokenring reduction enableset tokenring distrib-crf disable#vlansset vlan 999 name trbrf type trbrf bridge 0xe stp ieeeset vlan 200 name trcrf200 type trcrf parent 999 ring 0x64 mode srbset vlan 40 name trcrf40 type trcrf parent 999 ring 0x66 mode srbset vlan 998 name trbrf type trbrf bridge 0xd stp ieeeset vlan 300 name trcrf300 type trcrf parent 998 ring 0x65 mode srbset vlan 50 name trcrf50 type trcrf parent 998 ring 0x67 mode srb#add token port to trcrf 40set vlan 40 5/1#add token port to trcrf 50set vlan 50 5/2set trunk 1/2 onIP Routing between a TRISL VLAN and an Ethernet ISL VLAN
illustrates IP routing between a TRISL VLAN and an Ethernet ISL VLAN.
Figure 24
IP Routing between a TRISL VLAN and an Ethernet ISL VLAN
The following is the configuration for the router:
interface FastEthernet4/0.1ip address 5.5.5.1 255.255.255.0encapsulation tr-isl trbrf-vlan 999 bridge-num 14multiring trcrf-vlan 20 ring 100multiring all!interface FastEthernet4/0.2ip address 4.4.4.1 255.255.255.0encapsulation isl 12IPX Routing over ISL Configuration Example
shows IPX interior encapsulations configured over ISL encapsulation in VLAN configurations. Note that three different IPX encapsulation formats are used. VLAN 20 uses sap encapsulation, VLAN 30 uses arpa, and VLAN 70 uses novell-ether encapsulation. Prior to the introduction of this feature, only the default encapsulation format, "novell-ether," was available for routing IPX over ISLlinks in VLANs.
Figure 25 Configurable IPX Encapsulations Routed over ISL in VLAN Configurations
VLAN 20 Configuration
ipx routinginterface FastEthernet 2/0no shutdowninterface FastEthernet 2/0.20encapsulation isl 20ipx network 20 encapsulation sapVLAN 30 Configuration
ipx routinginterface FastEthernet 2/0no shutdowninterface FastEthernet 2/0.30encapsulation isl 30ipx network 30 encapsulation arpaVLAN 70
ipx routinginterface FastEthernet 3/0no shutdowninterface Fast3/0.70encapsulation isl 70ipx network 70 encapsulation novell-etherRouting with RIF between a TRISL VLAN and a Token Ring Interface
illustrates routing with RIF between a TRISL VLAN and a Token Ring interface.
Figure 26
Routing with RIF Between a TRISL VLAN and a Token Ring Interface
The following is the configuration for the router:
source-bridge ring-group 100!interface TokenRing 3/1ip address 4.4.4.1 255.255.255.0!interface FastEthernet4/0.1ip address 5.5.5.1 255.255.255.0encapsulation tr-isl trbrf 999 bridge-num 14multiring trcrf-vlan 200 ring-group 100multiring allThe following is the configuration for the Catalyst 5000 switch with the Token Ring switch module in slot 5. In this configuration, the Token Ring port 1 is assigned to the TrCRF VLAN 40.
#vtpset vtp domain trislset vtp mode serverset vtp v2 enable#dripset set tokenring reduction enableset tokenring distrib-crf disable#vlansset vlan 999 name trbrf type trbrf bridge 0xe stp ieeeset vlan 200 name trcrf200 type trcrf parent 999 ring 0x64 mode srtset vlan 40 name trcrf40 type trcrf parent 999 ring 0x1 mode srt#add token port to trcrf 40set vlan 40 5/1set trunk 1/2 onVIP Distributed Switching over ISL Configuration Example
illustrates a topology in which Catalyst VLAN switches are connected to routers forwarding traffic from a number of ISL VLANs. With the VIP distributed ISL capability in the Cisco 7500 series router, each VIP card can route ISL-encapsulated VLAN IP traffic. The inter-VLAN routing capacity is increased linearly by the packet-forwarding capability of each VIP card.
Figure 27 VIP Distributed ISL VLAN Traffic
In , the VIP cards forward the traffic between ISL VLANs or any other routing interface. Traffic from any VLAN can be routed to any of the other VLANs, regardless of which VIP card receives the traffic.
These commands show the configuration for each of the VLANs shown in :
interface FastEthernet1/0/0ip address 20.1.1.1 255.255.255.0ip route-cache distributedfull-duplexinterface FastEthernet1/0/0.1ip address 22.1.1.1 255.255.255.0encapsulation isl 1interface FastEthernet1/0/0.2ip address 22.1.2.1 255.255.255.0encapsulation isl 2interface FastEthernet1/0/0.3ip address 22.1.3.1 255.255.255.0encapsulation isl 3interface FastEthernet1/1/0ip route-cache distributedfull-duplexinterface FastEthernet1/1/0.1ip address 77.1.1.1 255.255.255.0encapsulation isl 4interface Fast Ethernet 2/0/0ip address 30.1.1.1 255.255.255.0ip route-cache distributedfull-duplexinterface FastEthernet2/0/0.5ip address 33.1.1.1 255.255.255.0encapsulation isl 5interface FastEthernet2/1/0ip address 40.1.1.1 255.255.255.0ip route-cache distributedfull-duplexinterface FastEthernet2/1/0.6ip address 44.1.6.1 255.255.255.0encapsulation isl 6interface FastEthernet2/1/0.7ip address 44.1.7.1 255.255.255.0encapsulation isl 7XNS Routing over ISL Configuration Example
To configure routing of the XNS protocol over ISL trunks, you need to define ISL as the encapsulation type. This example shows XNS configured to be routed over an ISL trunk.
Example XNS Configuration
xns routing 0123.4567.adcbinterface fastethernet 1/0.1encapsulation isl 100xns network 20
