Create a Virtual NNI Link Between Multi-Area Boundary Nodes

Before you begin

  • Create basic SPBM and IS-IS infrastructure.

  • Configure a CLIP interface.

About this task

Perform the following procedure to create a virtual NNI link between Multi-area boundary nodes.

Procedure

  1. Enter Loopback Interface Configuration mode

    enable

    configure terminal

    interface Loopback <1-256>

  2. Configure the loopback interface IP address to use as the source IP address for the Multi-area virtual NNI link:
    ip address {<A.B.C.D/x> | <A.B.C.D> <A.B.C.D>} multi-area-virtual-link <home | remote> [name WORD<0-64>]
  3. Exit the Loopback Configuration mode:
    exit
  4. Create a IS-IS logical interface for the Multi-area virtual NNI link:
    logical-intf isis <1-255> dest-ip <A.B.C.D> multi-area-virtual-link [name WORD<1-64>]
  5. Configure IS-IS on the logical interface:
    Note

    Note

    If you configure the loopback interface for the Multi-area virtual NNI link in the home area, you must configure IS-IS on the logical interface in the remote area, and vice versa.

    1. Create an IS-IS interface:
      isis [remote]
    2. Enable the SPBM instance on the IS-IS interface:
      isis [remote] spbm <1-100>
    3. Enable the IS-IS interface:
      isis [remote] enable
  6. Verify the configuration using the following commands:
    • show interfaces loopback
    • show isis logical-interface

Example

Configure a Multi-area virtual link NNI for the home area. To do this, create the loopback source to be redistributed in the remote area and then enable IS-IS on a virtual-link logical interface in the home area.

Switch:1>enable
Switch:1#configure terminal
Switch:1(config)#interface loopback 1
Switch:1(config-if)#ip address 2.2.2.2/32 multi-area-virtual-link remote
exit
Switch:1(config)#logical-intf isis 2 dest-ip 4.4.4.4 multi-area-virtual-link 
Switch:1(config-isis-2-4.4.4.4)#isis
Switch:1(config-isis-2-4.4.4.4)#isis spbm 1
Switch:1(config-isis-2-4.4.4.4)#isis enable
exit

Configure a Multi-area virtual NNI link for the remote area. To do this, create the loopback source to be redistributed in the home area and then enable IS-IS on a virtual-link logical interface in the remote area.

Switch:1>enable
Switch:1#configure terminal
Switch:1(config)#interface loopback 1
Switch:1(config-if)#ip address 2.2.2.2/32 multi-area-virtual-link home
exit
Switch:1(config)#logical-intf isis 2 dest-ip 4.4.4.4 multi-area-virtual-link
Switch:1(config-isis-2-4.4.4.4)#isis remote
Switch:1(config-isis-2-4.4.4.4)#isis remote spbm 1
Switch:1(config-isis-2-4.4.4.4)#isis remote enable
exit

The following example displays loopback interface information:

Switch:1#show interfaces loopback

===================================================================================================
                                Circuitless IP Interface - GlobalRouter
===================================================================================================
INTF IP_ADDRESS      NET_MASK          OSPF    PIM     AREA_ID     IF   IP             MULTI-AREA
ID                                     STATUS  STATUS              INDX NAME           VIRTUAL LINK
---------------------------------------------------------------------------------------------------
1    2.2.2.2         255.255.255.255   disable disable 0.0.0.0     1344 Virtual-link Remote
2    2.3.4.5         255.255.255.255   disable disable 0.0.0.0     1345
15   192.0.2.2       255.255.255.0     disable disable 0.0.0.0     1358 EXTR
======================================================================================================================
                                                Loopback Ipv6 Interface
======================================================================================================================
IF   VRF          Descr         VLAN PHYSICAL       ADMIN   OPER  TYPE  MTU  HOP REACHABLE   RETRANSMIT  IPSEC
INDX NAME                       ADDRESS             STATE   STATE            LMT TIME        TIME        STATE
----------------------------------------------------------------------------------------------------------------------
1234 GREEN        CLIPv6-11     00:00:00:00:00:0b   enable  up    ETHER 1500 64  30000       1000       disable
======================================================================================================================
                                                 Loopback IPv6 Address
======================================================================================================================
IPV6 ADDRESS/PREFIX LENGTH   LOOPBACK-ID  TYPE     ORIGIN     STATUS        VALID      PREF        NAME
                                                                            LIFETIME   LIFETIME
----------------------------------------------------------------------------------------------------------------------
2001:DB8:2000::1/128	     C-11	     UNICAST  MANUAL     PREFERRED     INF        INF         EXTRSER200

The following example displays logical interface information:

Switch:1>show isis logical-interface
===========================================================================================================================
                                                ISIS Logical Interfaces
===========================================================================================================================
IFIDX NAME       ENCAP L2_INFO  VIDS      TUNNEL   L3_TUNNEL_NEXT_HOP_INFO            BFD       TUNNEL    ORIGIN  ISIS  SDWAN    
                 TYPE  PORT/MLT (PRIMARY) DEST-IP  PORT/MLT      VLAN    VRF          STATUS    SRC-IP            MTU   OPER STATE
---------------------------------------------------------------------------------------------------------------------------
1 SD-WAN-1       IP     --      --       192.0.2.3    Port1/44    4047   sd-wan       disabled  192.0.2.1  ZTF     1400  UP
2 SPBoIP_T1      IP     --      --       192.0.2.15   Port1/25    500    vrf23        disabled  192.0.2.16 CONFIG  1000  N/A
3 SPBoIP_T2      IP     --      --       192.0.2.224  MLT10       2      vrf24        disabled  192.0.2.22 CONFIG  1600  N/A
4 Virtual-link-4 IP     --      --       4.4.4.4      PortRX-NNI  4051   GlobalRouter disabled  2.2.2.2    CONFIG  1600  N/A
5 Virtual-link-5 IP     --      --       5.5.5.5      Null        0      GlobalRouter disabled  2.2.2.2    CONFIG  1600  N/A
---------------------------------------------------------------------------------------------------------------------------
5 out of 5 Total Num of Logical ISIS interfaces 
---------------------------------------------------------------------------------------------------------------------------

Variable Definitions

The following table defines parameters for the ip address command.

Variable Value

<A.B.C.D/X>|<A.B.C.D> <A.B.C.D>

Specifies the IP address and subnet mask in the format A.B.C.D/X or A.B.C.D A.B.C.D.

multi-area-virtual-link

Specifies that the source IP address is used for a Mulit-area virtual NNI link.
<home | remote>

Specifies the transport area for the Multi-area virtual NNI link.

Note:

If you configure the loopback interface for the virtual NNI link in the home area, you must configure the IS-IS logical interface for the virtual NNI link in the remote area, and vice versa.

name WORD<0-64>

Specifies a name associated with the IP address.

Note:

If you do not assign a name when you configure virtual NNI links for Multi-Area boundary nodes for 7520 Series and 7720 Series, the system autogenerates the name and displays the name as Virtual-link.

The following tables define parameters for the logical-intf isis command.

Variable Value

<1-255>

Specifies the index number that uniquely identifies this logical interface.
dest-ip <A.B.C.D>

Specifies the destination IP address of the Multi-area virtual NNI link.

Note:

This IP address is the loopback source IP address.

multi-area-virtual-link

Specifies that the logical interface is used for a Multi-area virtual NNI link.

name WORD<1-64>

Specifies a name associated with the logical interface.

Note:

If you do not assign a name when you configure virtual NNI links for Multi-Area boundary nodes for 7520 Series and 7720 Series, the system autogenerates the name and displays the name as Virtual-link-x, where x is the logical interface ID.

The following tables define parameters for the isis command.

Variable Value

remote

Specifies the remote area as the IS-IS interface.

If the loopback interface for the virtual NNI link is configured in the remote area, omit this parameter.

enable

Enables the IS-IS interface for the virtual NNI link.

The default is disabled.
spbm <1-100>

Specifies the SPBM instance on the IS-IS interface.

9037806-02 Rev AB