Example for Importing IPv6 NDP Vlink Direct Routes to BGP4+

By importing IPv6 NDP Vlink direct routes to BGP4+, you can enable the remote device to obtain information about detailed routes in the VLAN, allowing precise control of data traffic.

Networking Requirements

As networks develop, the VLAN technology is widely used. If a user outside a VLAN needs to communicate with users within the VLAN, advertising routes destined for the network segment of the VLAN can achieve this purpose. When users outside the VLAN need to know the IPv6 NDP Vlink direct routes of the VLAN, and apply different traffic policies to routes of the VLAN users, advertising the routes destined for the network segment of the VLAN cannot meet this requirement. In this case, you can enable the function of IPv6 NDP Vlink direct route advertisement.

As shown in Figure 1, DeviceC is connected to two VLAN sites through VLANIF interfaces. DeviceD communicates with DeviceB, but not with DeviceA. You can enable the function of IPv6 NDP Vlink direct route advertisement on DeviceC, and use a route-policy to filter out the routes to the network segment of the VLAN and the route to DeviceA.

Figure 1 Networking diagram of importing IPv6 NDP Vlink direct routes to BGP4+

Interfaces 1 through 3 in this example represent GE 0/1/0, GE 0/1/8, and GE 0/1/16, respectively.



Configuration Roadmap

The configuration roadmap is as follows:

  1. Create VLANIF interfaces on SwitchA and DeviceC and assign IPv6 addresses to the VLANIF interfaces, and ensure that DeviceA, DeviceB, SwitchA, and DeviceC can communicate with each other.

  2. Enable BGP4+ on DeviceC and DeviceD, ensuring that DeviceC and DeviceD are able to advertise IPv6 routes to each other.

  3. Enable the function of IPv6 NDP Vlink direct route advertisement on DeviceC.

  4. Configure a route-policy on DeviceC, allowing IPv6 routes only from DeviceB to pass through.

  5. Enable BGP4+ on DeviceC and import IPv6 direct routes to BGP4+, and use the route-policy to import IPv6 routes only from DeviceB to BGP4+.

  6. Associate BGP4+ with the route-policy on DeviceC to filter out the network segment route of the VLAN so that DeviceD cannot learn the network segment route and can communicate with VLAN users based only on IPv6 NDP Vlink direct routes.

Data Preparation

To complete the configuration, you need the following data:

  • ID of the VLAN in which SwitchA and DeviceC reside (the VLAN ID is 10 in this example)

  • Router IDs and AS numbers of Devices C and D (router ID of DeviceC is 1.1.1.1 and router ID of DeviceD is 2.2.2.2, and Devices C and D are in AS 100 in this example)

  • Route-policy used to filter direct routes (the route-policy is policy1 in this example)

  • Route-policy used to advertise BGP4+ routes on DeviceC (the route-policy is policy2 in this example)

Procedure

  1. Configure an IP address for each interface.

    # Configure DeviceA.

    <HUAWEI> system-view
[~HUAWEI] sysname DeviceA
[*HUAWEI] commit
[~DeviceA] interface GigabitEthernet 0/1/0
[*DeviceA-GigabitEthernet0/1/0] ipv6 enable
[*DeviceA-GigabitEthernet0/1/0] ipv6 address 2001:db8:2000::3 64
[*DeviceA-GigabitEthernet0/1/0] commit
[~DeviceA-GigabitEthernet0/1/0] quit

    # Configure DeviceB.

    <HUAWEI> system-view
[~HUAWEI] sysname DeviceB
[*HUAWEI] commit
[~DeviceB] ipv6
[*DeviceB] interface GigabitEthernet 0/1/0
[*DeviceB-GigabitEthernet0/1/0] undo shutdown
[*DeviceB-GigabitEthernet0/1/0] ipv6 enable
[*DeviceB-GigabitEthernet0/1/0] ipv6 address 2001:db8:2000::4 64
[*DeviceB-GigabitEthernet0/1/0] commit
[~DeviceB-GigabitEthernet0/1/0] quit

    # Configure DeviceC.

    <HUAWEI> system-view
[~HUAWEI] sysname DeviceC
[*HUAWEI] commit
[~DeviceC] interface GigabitEthernet 0/1/8
[*DeviceC-GigabitEthernet0/1/8] ipv6 enable
[*DeviceC-GigabitEthernet0/1/8] ipv6 address 2001:db8:2001::1 64
[*DeviceC-GigabitEthernet0/1/8] commit
[~DeviceC-GigabitEthernet0/1/8] quit

    # Configure DeviceD.

    <HUAWEI> system-view
[~HUAWEI] sysname DeviceD
[*HUAWEI] commit
[~DeviceD] interface GigabitEthernet 0/1/0
[*DeviceD-GigabitEthernet0/1/0] ipv6 enable
[*DeviceD-GigabitEthernet0/1/0] ipv6 address 2001:db8:2001::2 64
[*DeviceD-GigabitEthernet0/1/0] commit
[~DeviceD-GigabitEthernet0/1/0] quit

  2. Configure basic VLAN functions. Create VLANIF 10 on SwitchA and DeviceC and assign IP addresses to the VLANIF interfaces.

    # Configure SwitchA.

    <HUAWEI> system-view
[~HUAWEI] sysname SwitchA
[*HUAWEI] commit
[~SwitchA] vlan 10
[*SwitchA-vlan10] quit
[*SwitchA] interface GigabitEthernet 0/1/0
[*SwitchA-GigabitEthernet0/1/0] portswitch
[*SwitchA-GigabitEthernet0/1/0] port link-type access
[*SwitchA-GigabitEthernet0/1/0] port default vlan 10
[*SwitchA-GigabitEthernet0/1/0] quit
[*SwitchA] interface GigabitEthernet 0/1/8
[*SwitchA-GigabitEthernet0/1/8] portswitch
[*SwitchA-GigabitEthernet0/1/8] port link-type access
[*SwitchA-GigabitEthernet0/1/8] port default vlan 10
[*SwitchA-GigabitEthernet0/1/8] quit
[*SwitchA] interface GigabitEthernet 0/1/16
[*SwitchA-GigabitEthernet0/1/16] portswitch
[*SwitchA-GigabitEthernet0/1/16] port link-type access
[*SwitchA-GigabitEthernet0/1/16] port default vlan 10
[*SwitchA-GigabitEthernet0/1/16] quit
[*SwitchA] interface Vlanif 10
[*SwitchA-Vlanif10] ipv6 enable
[*SwitchA-Vlanif10] ipv6 address 2001:db8:2000::2 64
[*SwitchA-Vlanif10] commit
[~SwitchA-Vlanif10] quit

    # Configure DeviceC.

    [~DeviceC] vlan 10
[*DeviceC-vlan10] quit
[*DeviceC] interface GigabitEthernet 0/1/0
[*DeviceC-GigabitEthernet0/1/0] portswitch
[*DeviceC-GigabitEthernet0/1/0] port link-type access
[*DeviceC-GigabitEthernet0/1/0] port default vlan 10
[*DeviceC-GigabitEthernet0/1/0] quit
[*DeviceC] interface Vlanif 10
[*DeviceC-Vlanif10] ipv6 enable
[*DeviceC-Vlanif10] ipv6 address 2001:db8:2000::1 64
[*DeviceC-Vlanif10] commit
[~DeviceC-Vlanif10] quit

  3. Configure BGP4+ between DeviceC and DeviceD.

    # Configure DeviceC.

    [~DeviceC] bgp 100
[*DeviceC-bgp] router-id 1.1.1.1
[*DeviceC-bgp] peer 2001:db8:2001::2 as-number 100
[*DeviceC-bgp] ipv6-family unicast
[*DeviceC-bgp-af-ipv6] peer 2001:db8:2001::2 enable
[*DeviceC-bgp-af-ipv6] commit
[~DeviceC-bgp-af-ipv6] quit
[~DeviceC-bgp] quit

    # Configure DeviceD.

    [~DeviceD] bgp 100
[*DeviceD-bgp] router-id 2.2.2.2
[*DeviceD-bgp] peer 2001:db8:2001::1 as-number 100
[*DeviceD-bgp] ipv6-family unicast
[*DeviceD-bgp-af-ipv6] peer 2001:db8:2001::1 enable
[*DeviceD-bgp-af-ipv6] commit
[~DeviceD-bgp-af-ipv6] quit
[~DeviceD-bgp] quit

    After the configuration is complete, run the display bgp ipv6 peer command to view statuses of IPv6 IBGP peer relationships. The command output shows that the IBGP peer relationship has been established between DeviceC and DeviceD. Use the display on DeviceD as an example.

    [~DeviceD] display bgp ipv6 peer
 BGP local router ID : 2.2.2.2
 Local AS number : 100
 Total number of peers : 1                 Peers in established state : 1

  Peer            V          AS  MsgRcvd  MsgSent  OutQ  Up/Down       State PrefRcv

  2001:db8:2001::1         4         100       64       59     0 00:52:15 Established       0

  4. Configure BGP4+ on DeviceC and import direct routes to BGP4+. Then view the routing tables of Devices C and D.

    # Configure DeviceC.

    [~DeviceC] bgp 100
[*DeviceC-bgp] ipv6-family unicast
[*DeviceC-bgp-af-ipv6] import-route direct
[*DeviceC-bgp-af-ipv6] commit
[~DeviceC-bgp-af-ipv6] quit
[~DeviceC-bgp] quit

    # Display the BGP4+ routing table of DeviceC.

    [~DeviceC] display bgp ipv6 routing-table
 BGP Local router ID is 1.1.1.1
 Status codes: * - valid, > - best, d - damped, x - best external, a - add path,
               h - history,  i - internal, s - suppressed, S - Stale
               Origin : i - IGP, e - EGP, ? - incomplete
 RPKI validation codes: V - valid, I - invalid, N - not-found

 Total Number of Routes: 12
 *>  Network  : ::1                                      PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : 2001:db8:2000::                          PrefixLen : 64
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : 2001:db8:2000::1                         PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : 2001:db8:2000::2                         PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : 2001:db8:2001::                          PrefixLen : 64
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : 2001:db8:2001::1                         PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : FE80::                                   PrefixLen : 10
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : FE80::2E0:39FF:FE18:8300                 PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : FE80::2E0:91FF:FE4F:8100                 PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : FE80::2E0:9BFF:FE7E:7800                 PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?

    # Display the BGP4+ routing table of DeviceD.

    [~DeviceD] display bgp ipv6 routing-table
 BGP Local router ID is 2.2.2.2
 Status codes: * - valid, > - best, d - damped, x - best external, a - add path,
               h - history,  i - internal, s - suppressed, S - Stale
               Origin : i - IGP, e - EGP, ? - incomplete
 RPKI validation codes: V - valid, I - invalid, N - not-found

 Total Number of Routes: 2
 *>i Network  : 2001:db8:2000::                          PrefixLen : 64
     NextHop  : 2001:db8:2001::1                         LocPrf    : 100
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
   i Network  : 2001:db8:2001::                          PrefixLen : 64
     NextHop  : 2001:db8:2001::1                         LocPrf    : 100
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?

    You can see that DeviceD has not learned the two IPv6 NDP Vlink direct routes 2001:db8:2000::3/128 and 2001:db8:2000::4/128.

  5. Enable the function of IPv6 NDP Vlink direct route advertisement on DeviceC and configure the route-policy policy1 to filter out the routes to the network segment of the VLAN and the IPv6 NDP Vlink direct route from DeviceA, 2001:db8:2000::3/128.

    # Configure DeviceC.

    [~DeviceC] ip ipv6-prefix prefix1 permit 2001:db8:2000::4 128
[*DeviceC] route-policy policy1 permit node 10
[*DeviceC-route-policy] if-match ipv6 address prefix-list prefix1
[*DeviceC-route-policy] quit
[*DeviceC] ipv6 nd vlink-direct-route advertise route-policy policy1
[*DeviceC] commit

    # Display the BGP4+ routing table of DeviceC.

    [~DeviceC] display bgp ipv6 routing-table
 BGP Local router ID is 1.1.1.1
 Status codes: * - valid, > - best, d - damped, x - best external, a - add path,
               h - history,  i - internal, s - suppressed, S - Stale
               Origin : i - IGP, e - EGP, ? - incomplete
 RPKI validation codes: V - valid, I - invalid, N - not-found

 Total Number of Routes: 12
 *>  Network  : ::1                                      PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : 2001:db8:2000::                          PrefixLen : 64
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : 2001:db8:2000::1                         PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : 2001:db8:2000::2                         PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : 2001:db8:2000::3                         PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : 2001:db8:2000::4                         PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : 2001:db8:2001::                          PrefixLen : 64
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : 2001:db8:2001::1                         PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : FE80::                                   PrefixLen : 10
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : FE80::2E0:39FF:FE18:8300                 PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : FE80::2E0:91FF:FE4F:8100                 PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>  Network  : FE80::2E0:9BFF:FE7E:7800                 PrefixLen : 128
     NextHop  : ::                                       LocPrf    :
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?

    # Display the BGP4+ routing table of DeviceD.

    [~DeviceD] display bgp ipv6 routing-table
 BGP Local router ID is 2.2.2.2
 Status codes: * - valid, > - best, d - damped, x - best external, a - add path,
               h - history,  i - internal, s - suppressed, S - Stale
               Origin : i - IGP, e - EGP, ? - incomplete
 RPKI validation codes: V - valid, I - invalid, N - not-found

 Total Number of Routes: 3
 *>i Network  : 2001:db8:2000::                          PrefixLen : 64
     NextHop  : 2001:db8:2001::1                         LocPrf    : 100
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
 *>i Network  : 2001:db8:2000::4                         PrefixLen : 128
     NextHop  : 2001:db8:2001::1                         LocPrf    : 100
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
   i Network  : 2001:db8:2001::                          PrefixLen : 64
     NextHop  : 2001:db8:2001::1                         LocPrf    : 100
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?

    You can see that DeviceD has learned the IPv6 NDP Vlink direct route 2001:db8:2000::4/128, whereas the route 2001:db8:2000::3/128 has been filtered out.

  6. Use the route-policy policy2 to filter out the network segment route 2001:db8:2000::/64 on DeviceC when BGP4+ routes are advertised.

    # Configure DeviceC.

    [~DeviceC] ip ipv6-prefix prefix2 index 10 deny 2001:db8:2000:: 64
[*DeviceC] ip ipv6-prefix prefix2 index 20 permit :: 0 less-equal 128
[*DeviceC] route-policy policy2 permit node 10
[*DeviceC-route-policy] if-match ipv6 address prefix-list prefix2
[*DeviceC-route-policy] quit
[*DeviceC] bgp 100
[*DeviceC-bgp] ipv6-family unicast
[*DeviceC-bgp-af-ipv6] peer 2001:db8:2001::2 route-policy policy2 export
[*DeviceC-bgp-af-ipv6] commit
[~DeviceC-bgp-af-ipv6] quit
[~DeviceC-bgp] quit
[~DeviceC] quit
<DeviceC> refresh bgp all export

    # Display the BGP4+ routing table of DeviceD.

    [~DeviceD] display bgp ipv6 routing-table
 BGP Local router ID is 2.2.2.2
 Status codes: * - valid, > - best, d - damped, x - best external, a - add path,
               h - history,  i - internal, s - suppressed, S - Stale
               Origin : i - IGP, e - EGP, ? - incomplete
 RPKI validation codes: V - valid, I - invalid, N - not-found

 Total Number of Routes: 2
 *>i Network  : 2001:db8:2000::4                         PrefixLen : 128
     NextHop  : 2001:db8:2001::1                         LocPrf    : 100
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?
   i Network  : 2001:db8:2001::                          PrefixLen : 64
     NextHop  : 2001:db8:2001::1                         LocPrf    : 100
     MED      : 0                                        PrefVal   : 0
     Label    :
     Path/Ogn : ?

    You can see that the route 2001:db8:2000::/64 does not exist in the BGP4+ routing table of DeviceD. As a result, DeviceD can communicate with DeviceB, but cannot communicate with DeviceA.

Configuration Files

  • Configuration file of SwitchA

    #
sysname switchA
#
vlan batch 10
#
interface Vlanif10
 ipv6 enable
 ipv6 address 2001:db8:2000::2/64
#
interface GigabitEthernet0/1/0
 portswitch
 undo shutdown
 port link-type access
 port default vlan 10
#
interface GigabitEthernet0/1/8
 portswitch
 undo shutdown
 port link-type access
 port default vlan 10
#
interface GigabitEthernet0/1/16
 portswitch
 undo shutdown
 port link-type access
 port default vlan 10
#
return

  • Configuration file of DeviceA

    #
sysname DeviceA
#
interface GigabitEthernet0/1/0
 undo shutdown
 ipv6 enable
 ipv6 address 2001:db8:2000::3/64
#
return

  • Configuration file of DeviceB

    #
sysname DeviceB
#
interface GigabitEthernet0/1/0
 undo shutdown
 ipv6 enable
 ipv6 address 2001:db8:2000::4/64
#
return

  • Configuration file of DeviceC

    #
sysname DeviceC
#
ip ipv6-prefix prefix1 index 10 permit 2001:db8:2000::4 128
ip ipv6-prefix prefix2 index 10 deny 2001:db8:2000:: 64
ip ipv6-prefix prefix2 index 20 permit :: 0 less-equal 128
#
route-policy policy1 permit node 10
 if-match ip-prefix prefix1
 if-match ipv6 address prefix-list prefix1
#
route-policy policy2 permit node 10
 if-match ipv6 address prefix-list prefix2
#
ipv6 nd vlink-direct-route advertise route-policy policy1
#
vlan batch 10
#
interface Vlanif10
 ipv6 enable
 ipv6 address 2001:db8:2000::1/64
#
interface GigabitEthernet0/1/0
 portswitch
 undo shutdown
 port link-type access
 port default vlan 10
#
interface GigabitEthernet0/1/8
 undo shutdown
 ipv6 enable
 ipv6 address 2001:db8:2001::1/64
#
bgp 100
 router-id 1.1.1.1
 peer 2001:db8:2001::2 as-number 100
 #
 ipv4-family unicast
  undo synchronization 
 #
 ipv6-family unicast
  undo synchronization 
  import-route direct
  peer 2001:db8:2001::2 enable
  peer 2001:db8:2001::2 route-policy policy2 export
#
return

  • Configuration file of DeviceD

    #
sysname DeviceD
#
interface GigabitEthernet0/1/0
 undo shutdown
 ipv6 enable
 ipv6 address 2001:db8:2001::2/64
#
bgp 100
 router-id 2.2.2.2
 peer 2001:db8:2001::1 as-number 100
 #
 ipv4-family unicast
  undo synchronization 
 #
 ipv6-family unicast
  undo synchronization 
  peer 2001:db8:2001::1 enable
#
return
Parent Topic: Configuration Examples for IP Routing Basis
Copyright © Huawei Technologies Co., Ltd.
Copyright © Huawei Technologies Co., Ltd.
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