Table of Contents
Multiprotocol Label Switching
Prerequisites
MPLS Edge Label Switch Router
PVP Example: Configuring and Connecting Edge LSRs in Separate Cisco 6400s
Multiprotocol Label Switching
This chapter provides examples, restrictions, and prerequisites for multiprotocol label switching (MPLS) features supported by the Cisco 6400 in Cisco IOS Release 12.2(2)B.
This chapter only includes information that is specific to the Cisco 6400 and supplements the MPLS overview, configuration, verification, monitoring, and troubleshooting information in the Cisco IOS Switching Services Configuration Guide and the ATM Switch Router Software Configuration Guide (where MPLS is called "Tag Switching").
This chapter includes the following sections:
For a complete list of MPLS and MPLS-related features supported in Cisco IOS Release 12.2(2)B, see the "Supported Features" chapter.
Restrictions
While configured as an MPLS Label Switch Controller (LSC), the NRP-2 or NRP-2SV can only support LSC functionality. The NRP-1 can also support network management on the Ethernet interface while configured as an MPLS LSC.
Prerequisites
In order to use the Cisco 6400 as an MPLS device, you must enable Cisco express forwarding (CEF) switching on each NRP with the ip cef global configuration command.
Split horizon is disabled by default on ATM interfaces. If you are running RIP in your MPLS VPNs, you must enable split horizon. See the "Split Horizon and RIP Example" section for an example.
MPLS Edge Label Switch Router
Cisco 6400 NRPs can be configured as MPLS Edge LSRs that can be connected across MPLS networks by using permanent virtual paths (PVPs) or a virtual path identifier (VPI) range. The following sections provide simple examples of each scenario.
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Note The Cisco 6400 NRP performs Edge LSR routing in compliance with RFC 1483 (aal5snap). Running any additional access protocols (such as PPP, RBE, or L2TP) on the same NRP is not supported. |
The Edge LSR examples do not show the connections to the routers external to the MPLS network, but packets can enter and exit the MPLS network through the FastEthernet (FE) port on the Edge LSR NRP, or through a node line card (NLC) in the same Cisco 6400. The examples also do not show the devices within the MPLS or ATM network.
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Note The recommended method of using an NSP to connect two MPLS Edge LSRs is to configure the NSP as a virtual path (VP) switch. A VP switch configuration is also recommended for an NSP connecting an MPLS Edge LSR to an ATM LSR. To configure the Cisco 6400 NSP as a VP switch, see the "Internal Cross-Connections" section of the "Basic NSP Configuration" chapter of the Cisco 6400 Software Setup Guide . |
MPLS Edge LSRs Connected Through a PVP
The PVP configuration through the NSP provides transparent NSP redundancy. The NSP switchover does not preserve label virtual circuits (LVCs) unless they are aggregated into a PVP.
PVP Example: Configuring and Connecting Edge LSRs Within a Cisco 6400
In this example, two NRPs are configured as Edge LSRs in the same Cisco 6400. The Edge LSRs are connected to each other through a PVP through the switch fabric of the Cisco 6400, as shown in Figure 3-1.
Figure 3-1: PVP Connection Between Two Edge LSRs Within a Cisco 6400
The following example shows the configuration for NRP1 in Slot 1:
NRP1# configure terminal NRP1(config)# ip cef NRP1(config)# tag-switching ip NRP1(config)# interface ATM0/0/0.1 tag-switching NRP1(config-if)# ip unnumbered Loopback0 NRP1(config-if)# atm pvc 40 40 0 aal5snap NRP1(config-if)# tag-switching atm vp-tunnel 40 NRP1(config-if)# tag-switching ip
The following example shows the configuration for NRP2 in Slot 2:
NRP2# configure terminal NRP2(config)# ip cef NRP2(config)# tag-switching ip NRP2(config)# interface ATM0/0/0.1 tag-switching NRP2(config-if)# ip unnumbered Loopback0 NRP2(config-if)# atm pvc 40 40 0 aal5snap NRP2(config-if)# tag-switching atm vp-tunnel 40 NRP2(config-if)# tag-switching ip
To complete the PVP connection between NRP1 and NRP2 in Figure 1, the NSP must be configured to set the path through the switch fabric. The following example shows the VP-switch configuration for the NSP:
NSP# configure terminal NSP(config)# interface ATM1/0/0 NSP(config-if)# atm pvp 40 interface ATM2/0/0 40
PVP Example: Configuring and Connecting Edge LSRs in Separate Cisco 6400s
In this example, two NRPs are configured as Edge LSRs in the separate Cisco 6400s. The Edge LSRs are connected to each other through a PVP through the MPLS network, as shown in Figure 3-2.
Figure 3-2: PVP Connection Between Two Edge LSRs in Separate Cisco 6400s
The following example shows the configuration for NRP1 in Slot 1 of Cisco 6400 A:
NRP1# configure terminal NRP1(config)# ip cef NRP1(config)# tag-switching ip NRP1(config)# interface ATM0/0/0.1 tag-switching NRP1(config-if)# ip unnumbered Loopback0 NRP1(config-if)# atm pvc 40 40 0 aal5snap NRP1(config-if)# tag-switching atm vp-tunnel 40 NRP1(config-if)# tag-switching ip
The following example shows the configuration for NRP2 in Slot 1 of Cisco 6400 B:
NRP2# configure terminal NRP2(config)# ip cef NRP2(config)# tag-switching ip NRP2(config)# interface ATM0/0/0.1 tag-switching NRP2(config-if)# ip unnumbered Loopback0 NRP2(config-if)# atm pvc 40 40 0 aal5snap NRP2(config-if)# tag-switching atm vp-tunnel 40 NRP2(config-if)# tag-switching ip
To complete the PVP connection between NRP1 and NRP2 in Figure 1, the NSPs must be configured to set the path through the switch fabric and node line cards (NLCs).
The following example shows the VP-switch configuration for NSP1 in Cisco 6400 A:
NSP1# configure terminal NSP1(config)# interface ATM1/0/0 NSP1(config-if)# atm pvp 40 interface ATM8/0/0 40
The following example shows the VP-switch configuration for NSP2 in Cisco 6400 B:
NSP2# configure terminal NSP2(config)# interface ATM1/0/0 NSP2(config-if)# atm pvp 40 interface ATM8/0/0 40
MPLS Edge LSRs Connected Through a VPI Range
In addition to providing transparent NSP redundancy, configuring a VPI Range to connect two MPLS Edge LSRs enables you to accommodate a large number of LVCs. For more information on VPI ranges, see the "Configuring a VPI Range" section in the "Configuring Tag Switching" chapter in the ATM Switch Router Software Configuration Guide.
VPI Range Example: Configuring and Connecting Edge LSRs Within a Cisco 6400
In this example, two NRPs are configured as Edge LSRs in the same Cisco 6400. The Edge LSRs are connected to each other through a VPI range through the switch fabric of the Cisco 6400, as shown in Figure 3-3.
Figure 3-3: VPI Range Between Two Edge LSRs Within a Cisco 6400
The following example shows the configuration for NRP1 in Slot 1:
NRP1# configure terminal NRP1(config)# ip cef NRP1(config)# tag-switching ip NRP1(config)# interface ATM0/0/0.1 tag-switching NRP1(config-if)# ip unnumbered Loopback0 NRP1(config-if)# tag-switching atm vpi 7-10 NRP1(config-if)# tag-switching ip
The following example shows the configuration for NRP2 in Slot 2:
NRP2# configure terminal NRP2(config)# ip cef NRP2(config)# tag-switching ip NRP2(config)# interface ATM0/0/0.1 tag-switching NRP2(config-if)# ip unnumbered Loopback0 NRP2(config-if)# tag-switching atm vpi 7-10 NRP2(config-if)# tag-switching ip
To complete the VPI range connection between NRP1 and NRP2 in Figure 1, the NSP must be configured to set the paths through the switch fabric. PVP 0 is used to set up the control channels. The following example shows the VP-switch configuration for the NSP:
NSP# configure terminal NSP(config)# interface ATM1/0/0 NSP(config-if)# atm pvp 7 interface ATM2/0/0 7 NSP(config-if)# atm pvp 8 interface ATM2/0/0 8 NSP(config-if)# atm pvp 9 interface ATM2/0/0 9 NSP(config-if)# atm pvp 10 interface ATM2/0/0 10 NSP(config-if)# atm pvp 0 interface ATM2/0/0 0
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Note This example uses the default control channel PVC 0/32. You can also use a channel within the configured VPI range by using the tag-switching atm control-vc interface configuration command on the NRPs. For example, if you want to use the control channel PVC 7/32, then enter tag-switching atm control-vc 7 32 on both NRP1 and NRP2. |
VPI Range Example: Configuring and Connecting Edge LSRs in Separate Cisco 6400s
In this example, two NRPs are configured as Edge LSRs in the separate Cisco 6400s. The Edge LSRs are connected to each other through a VPI range through the MPLS network, as shown in Figure 3-4.
Figure 3-4: VPI Range Between Two NRPs in Different Cisco 6400s
The following example shows the configuration for NRP1 in Slot 1 of Cisco 6400 A:
NRP1# configure terminal NRP1(config)# ip cef NRP1(config)# tag-switching ip NRP1(config)# interface ATM0/0/0.1 tag-switching NRP1(config-if)# ip unnumbered Loopback0 NRP1(config-if)# tag-switching atm vpi 7-10 NRP1(config-if)# tag-switching ip
The following example shows the configuration for NRP2 in Slot 1 of Cisco 6400 B:
NRP2# configure terminal NRP2(config)# ip cef NRP2(config)# tag-switching ip NRP2(config)# interface ATM0/0/0.1 tag-switching NRP2(config-if)# ip unnumbered Loopback0 NRP2(config-if)# tag-switching atm vpi 7-10 NRP2(config-if)# tag-switching ip
To complete the VPI range connection between NRP1 and NRP2 in Figure 1, the NSPs must be configured to set the path through the switch fabric and node line cards (NLCs). PVP 0 is used to set up the control channels.
The following example shows the VP-switch configuration for NSP1 in Cisco 6400 A:
NSP# configure terminal NSP(config)# interface ATM1/0/0 NSP(config-if)# atm pvp 7 interface ATM8/0/0 7 NSP(config-if)# atm pvp 8 interface ATM8/0/0 8 NSP(config-if)# atm pvp 9 interface ATM8/0/0 9 NSP(config-if)# atm pvp 10 interface ATM8/0/0 10 NSP(config-if)# atm pvp 0 interface ATM8/0/0 0
The following example shows the VP-switch configuration for NSP2 in Cisco 6400 B:
NSP# configure terminal NSP(config)# interface ATM1/0/0 NSP(config-if)# atm pvp 7 interface ATM8/0/0 7 NSP(config-if)# atm pvp 8 interface ATM8/0/0 8 NSP(config-if)# atm pvp 9 interface ATM8/0/0 9 NSP(config-if)# atm pvp 10 interface ATM8/0/0 10 NSP(config-if)# atm pvp 0 interface ATM8/0/0 0
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Note This example uses the default control channel PVC 0/32. You can also use a channel within the configured VPI range by using the tag-switching atm control-vc interface configuration command on the NRPs. For example, if you want to use the control channel PVC 7/32, then enter tag-switching atm control-vc 7 32 on both NRP1 and NRP2. |
MPLS Virtual Private Networks
For general MPLS VPN configuration tasks, examples, and command references, see the "Multiprotocol Label Switching" chapter in the Cisco IOS Switching Services Configuration Guide.
In addition to these configurations, you must configure the NSP to create paths through the switch fabric of the Cisco 6400. The switch fabric provides connectivity between the NRPs and the external ports on the node line cards (NLCs). For general configuration tasks, examples, and command references for configuring paths through the switch fabric, see the "Configuring Virtual Connections" chapter in the ATM Switch Router Software Configuration Guide.
The examples in this section illustrate the configurations necessary to enable MPLS VPN on a Cisco 6400.
Basic MPLS VPN Configuration Example
This section presents a basic Cisco 6400 MPLS VPN configuration. As shown in Figure 3-5, three customer edge (CE) routers are connected to the service provider backbone through three provider edge (PE) routers. Two of the PE routers are NRPs in the Cisco 6400, while the third PE router is a Cisco 7200. CE1 uses dual homing with PE1 and PE3.
CE1 and CE2 are devices in VPN1, while CE3 is in VPN2. PE1, or NRP1 in the Cisco 6400, handles the CE1 portion of VPN1. PE2, or NRP2 in the Cisco 6400, handles VPN2 as well as the CE2 portion of VPN1.
Figure 3-5: Basic Cisco 6400 MPLS VPN Topology
To enable a Cisco 6400 NRP to participate in a VPN, you must configure the NSP to create paths from the NRP through the Cisco 6400 switch fabric. The switch fabric provides the only connection between the NRP and an external port on a network line card (NLC). The switch fabric also provides the only connection between NRPs in the same Cisco 6400. Figure 3-6 shows a detailed schematic of the configuration used in the topology shown in Figure 3-5.
As shown in the accompanying configurations, you can use routed (in compliance with RFC 1483) PVCs for the CE to PE connections, as long as the CE router is capable of performing routing in compliance with RFC 1483 (aal5snap).
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Note Each NRP in a Cisco 6400 is capable of handling multiple VPNs. |
Figure 3-6: Detailed Schematic of the MPLS VPN Configuration Shown in Figure 3-5
PE1: Cisco 6400 NRP1
PE1 in Figure 3-6 is connected to PE3, through VP 42, and CE1, through PVC 35/70. In addition, PE1 and PE2, both NRPs in the same Cisco 6400, are connected to each other through VP40.
The following example shows the complete configuration for PE1 (Cisco 6400 NRP1):
! ip cef ip classless ! interface Loopback0 ip address 10.10.10.10 255.255.255.255 no ip directed-broadcast ! !The following fragment defines a VPN routing/forwarding (VRF) instance on PE1
!and imports routes from VPN2 to the VRF VPN1 routing table. ! ip vrf vpn1 rd 100:1 route-target export 100:1 route-target import 100:1 route-target import 200:1 no tag-switching aggregate-statistics ! !The following fragment creates VP 40 and VP 42 through the MPLS cloud. ! interface ATM0/0/0.1 tag-switching ip unnumbered Loopback0 no ip directed-broadcast ip split-horizon atm pvc 40 40 0 aal5snap tag-switching atm vp-tunnel 40 tag-switching ip ! interface ATM0/0/0.3 tag-switching ip unnumbered Loopback0 no ip directed-broadcast ip split-horizon atm pvc 42 42 0 aal5snap tag-switching atm vp-tunnel 42 tag-switching ip ! !The following fragment associates an interface with a VRF on PE1. ! interface ATM0/0/0.2 point-to-point ip vrf forwarding vpn1 ip address 10.30.0.1 255.255.0.0 no ip directed-broadcast ip split-horizon atm pvc 70 35 70 aal5snap ! !The following fragment configures Interior Gateway Protocol (IGP) routing on PE1. ! router ospf 100 passive-interface ATM0/0/0.2 network 10.0.0.0 0.255.255.255 area 100 ! !The following fragment configures Routing Information Protocol (RIP)
!between PE1 and CE1. You can also use Border Gateway Protocol (BGP) or
!static routing instead of RIP. ! router rip version 2 ! address-family ipv4 vrf vpn1 version 2 redistribute bgp 100 metric transparent network 10.30.0.0 no auto-summary exit-address-family ! !The following fragment configures internal BGP sessions among the PE routers. ! router bgp 100 no synchronization no bgp default ipv4-unicast neighbor 10.11.11.11 remote-as 100 neighbor 10.11.11.11 update-source Loopback0 neighbor 10.12.12.12 remote-as 100 neighbor 10.12.12.12 update-source Loopback0 ! address-family ipv4 vrf vpn1 redistribute rip no auto-summary no synchronization exit-address-family ! address-family vpnv4 neighbor 10.11.11.11 activate neighbor 10.11.11.11 send-community extended neighbor 10.12.12.12 activate neighbor 10.12.12.12 send-community extended exit-address-family !
PE2: Cisco 6400 NRP2
PE2 in Figure 3-6 is connected to CE2, through PVC 55/60, and CE3, through PVC 45/50. In addition, PE1 and PE2, both NRPs in the same Cisco 6400, are connected to each other through VP40.
The following example shows the complete configuration for PE2 (Cisco 6400 NRP2):
! ip cef ip classless ! interface Loopback0 ip address 10.11.11.11 255.255.255.255 no ip directed-broadcast ! !The following fragment defines the VRF instances on PE2. The fragment also
!imports the routes from VPN2 to the VRF VPN1 routing table and imports the
!routes from VPN1 to the VRF VPN2 routing table. ! ip vrf vpn1 rd 100:1 route-target export 100:1 route-target import 100:1 route-target import 200:1 ! ip vrf vpn2 rd 200:1 route-target export 200:1 route-target import 200:1 route-target import 100:1 ! !The following fragment creates VP 40 through the MPLS cloud. ! interface ATM0/0/0.1 tag-switching ip unnumbered Loopback0 no ip directed-broadcast ip split-horizon atm pvc 40 40 0 aal5snap tag-switching atm vp-tunnel 40 tag-switching ip ! !The following fragment associates interfaces with VRFs on PE2. ! interface ATM0/0/0.2 point-to-point ip vrf forwarding vpn2 ip address 10.32.0.1 255.255.0.0 no ip directed-broadcast ip split-horizon atm pvc 50 45 50 aal5snap ! interface ATM0/0/0.3 point-to-point ip vrf forwarding vpn1 ip address 10.31.0.1 255.255.0.0 no ip directed-broadcast ip split-horizon atm pvc 60 55 60 aal5snap ! !The following fragment configures IGP routing on PE2. ! router ospf 100 passive-interface ATM0/0/0.2 passive-interface ATM0/0/0.3 network 10.11.0.0 0.0.255.255 area 100 ! !The following fragment configures RIP between PE2 and CE2, as well as
!between PE2 and CE3. You can also use Border Gateway Protocol (BGP) or
!static routing instead of RIP. ! router rip version 2 ! address-family ipv4 vrf vpn2 version 2 redistribute bgp 100 metric transparent network 10.32.0.0 no auto-summary exit-address-family ! address-family ipv4 vrf vpn1 version 2 redistribute bgp 100 metric transparent network 10.31.0.0 no auto-summary exit-address-family ! !The following fragment configures internal BGP sessions among the PE routers. ! router bgp 100 no synchronization no bgp default ipv4-unicast neighbor 10.10.10.10 remote-as 100 neighbor 10.10.10.10 update-source Loopback0 neighbor 10.12.12.12 remote-as 100 neighbor 10.12.12.12 update-source Loopback0 ! address-family ipv4 vrf vpn2 redistribute rip no auto-summary no synchronization exit-address-family ! address-family ipv4 vrf vpn1 redistribute rip no auto-summary no synchronization exit-address-family ! address-family vpnv4 neighbor 10.10.10.10 activate neighbor 10.10.10.10 send-community extended neighbor 10.12.12.12 activate neighbor 10.12.12.12 send-community extended exit-address-family !
PE1 and PE2 Connectivity: Cisco 6400 NSP
The following example shows the configuration necessary for the PE Cisco 6400 NSP to create the paths in the switch fabric between the NRPs and the OC3 line cards shown in Figure 3-6.
!The following fragment creates VP 42 between
!an OC3 (slot 8, card 1, port 0) and NRP1. ! interface ATM8/1/0 atm pvp 42 interface ATM1/0/0 42 ! !The following fragment creates PVC 35/70 between
!an OC3 (slot 8, card 0, port 0) and NRP1. ! interface ATM8/0/0 atm pvc 35 70 interface ATM1/0/0 35 70 ! !The following fragment creates VP 40 between NRP1 in Slot 1
!and NRP2 in Slot 3.: ! interface ATM3/0/0 atm pvp 40 interface ATM1/0/0 40 ! !The following fragment creates PVC 55/60 between
!an OC3 (slot 8, card 1, port 1) and NRP2. ! interface ATM8/1/1 atm pvc 55 60 interface ATM3/0/0 55 60 ! !The following fragment creates PVC 45/50 between
!an OC3 (slot 8, card 0, port 1) and NRP2. ! interface ATM8/0/1 atm pvc 45 50 interface ATM3/0/0 45 50 !
PE3: Cisco 7200
PE3 in Figure 3-6 is connected to PE1, through VP 42, and CE1, through a packet over SONET (POS) link.
The following example shows the complete configuration for PE3 (Cisco 7200):
ip cef ip classless ! interface Loopback0 ip address 10.12.12.12 255.255.255.255 no ip directed-broadcast ! !The following fragment defines the VRF instances on PE3. ! ip vrf vpn1 rd 100:1 route-target export 100:1 route-target import 100:1 route-target import 200:1 isdn voice-call-failure 0 ! !The following fragment associates a POS interface with a VRF on PE3. ! interface POS3/0 ip vrf forwarding vpn1 ip address 10.33.0.1 255.255.0.0 no ip directed-broadcast no keepalive clock source internal ! !The following fragment creates VP 42 through the MPLS cloud. ! interface ATM2/0.1 tag-switching ip unnumbered Loopback0 no ip directed-broadcast ip split-horizon atm pvc 42 42 0 aal5snap tag-switching atm vp-tunnel 42 tag-switching ip ! !The following fragment configures IGP routing on PE3. ! router ospf 100 passive-interface POS3/0 network 10.12.0.0 0.0.255.255 area 100 ! !The following fragment configures RIP between PE3 and CE1.
!You can also use BGP or static routing instead of RIP. ! router rip version 2 ! address-family ipv4 vrf vpn1 version 2 redistribute bgp 100 metric transparent network 10.33.0.0 no auto-summary exit-address-family ! !The following fragment configures internal BGP sessions
!among the PE routers. ! router bgp 100 no synchronization no bgp default ipv4-unicast neighbor 10.10.10.10 remote-as 100 neighbor 10.10.10.10 update-source Loopback0 neighbor 10.11.11.11 remote-as 100 neighbor 10.11.11.11 update-source Loopback0 ! address-family ipv4 vrf vpn1 redistribute rip no auto-summary no synchronization exit-address-family ! address-family vpnv4 neighbor 10.10.10.10 activate neighbor 10.10.10.10 send-community extended neighbor 10.11.11.11 activate neighbor 10.11.11.11 send-community extended exit-address-family !
CE1: Cisco 7500
CE1 in Figure 3-6 is connected to PE1, through PVC 35/70, and PE3, through a packet over SONET (POS) link.
The following example shows the configuration for CE1 (Cisco 7500):
! ip cef ip classless ! interface Loopback0 ip address 10.13.13.13 255.255.255.255 no ip directed-broadcast ! !The following fragment creates the POS link between CE1 and PE3. ! interface POS4/0/0 ip address 10.33.0.2 255.255.0.0 no ip directed-broadcast no ip route-cache distributed no keepalive clock source internal ! !The following fragment creates PVC 35/70. ! interface ATM2/0/0.2 point-to-point ip address 10.30.0.2 255.255.0.0 no ip directed-broadcast ip split-horizon atm pvc 70 35 70 aal5snap ! !The following fragment configures RIP on CE1.
!You can also use BGP or static routing instead of RIP: ! router rip version 2 network 10.13.0.0 network 10.30.0.0 network 10.33.0.0 !
CE2: Cisco 7200
CE2 in Figure 3-6 is connected to PE2, through PVC 55/60.
The following example shows the configuration for the CE2 (Cisco 7200):
! ip cef ip classless ! interface Loopback0 ip address 10.15.15.15 255.255.255.255 no ip directed-broadcast ! !The following fragment creates PVC 55/60. ! interface ATM2/0.2 point-to-point ip address 10.31.0.2 255.255.0.0 no ip directed-broadcast ip split-horizon atm pvc 60 55 60 aal5snap ! !The following fragment configures RIP on CE2.
!You can also use BGP or static routing instead of RIP: ! router rip version 2 network 10.15.0.0 network 10.31.0.0 !
CE3: Cisco 7500
CE3 in Figure 3-6 is connected to PE2, through PVC 45/50.
The following example shows the configuration for CE3 (Cisco 7500):
! ip cef ip classless ! interface Loopback0 ip address 10.14.14.14 255.255.255.255 no ip directed-broadcast ! !The following fragment creates PVC 45/50. ! interface ATM1/0/0.1 point-to-point ip address 10.32.0.2 255.255.0.0 no ip directed-broadcast ip split-horizon atm pvc 50 45 50 aal5snap ! !The following fragment configures RIP on CE3.
!You can also use BGP or static routing instead of RIP. ! router rip version 2 network 10.14.0.0 network 10.32.0.0 !
Split Horizon and RIP Example
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Note Split horizon is disabled by default on ATM interfaces. If you are running RIP in your VPNs, you must enable split horizon. |
The following example shows a typical configuration for an ATM subinterface on an NRP:
NRP# configure terminal NRP(config)# interface ATM0/0/0.1 tag-switching NRP(config-if)# ip unnumbered Loopback0 NRP(config-if)# ip split-horizon NRP(config-if)# no ip directed-broadcast NRP(config-if)# atm pvc 40 40 0 aal5snap NRP(config-if)# tag-switching atm vp-tunnel 40 NRP(config-if)# tag-switching ip