Example for Configuring Inter-AS Seamless MPLS+HVPN

In the inter-AS seamless MPLS+HVPN networking, an HVPN connection between a CSG and AGG is established, and an inter-AS seamless MPLS LSP between an AGG and MASG is established. The inter-AS seamless MPLS+HVPN networking obtains the collective advantages of the inter-AS seamless MPLS network and HVPN.

Networking Requirements

In Figure 1, the access and aggregation layers belong to one AS, and the core layer belongs to another AS. Before VPN services is provisioned, the inter-AS seamless MPLS+HVPN networking can be deployed. This networking allows NodeBs and the RNC to communicate and has low networking construction costs because of HVPN techniques. An HVPN connection between each pair of a CSG and AGG is established, and an inter-AS seamless MPLS LSP between each pair of an AGG and MASG is established.

Figure 1 Inter-AS seamless MPLS+HVPN networking (1)

Addresses of interfaces are planned for the CSGs, AGGs, AGG ASBRs, core ASBRs, and MASGs shown in Figure 2.

Figure 2 Inter-AS seamless MPLS+HVPN networking (2)

Configuration Roadmap

The configuration roadmap is as follows:

Configure IGP protocols at the access, aggregation, and core layers to implement network connectivity at each layer.
Configure MPLS and MPLS LDP and establish MPLS LSPs at the access, aggregation, and core layers.
Establish IBGP peer relationships at the aggregation and core layers and enable devices to exchange labeled routes.
Configure an EBGP peer relationship between each pair of an AGG ASBR and core ASBR and enable these devices to exchange labeled routes across ASs.
Configure a routing policy to control label distribution for a BGP LSP to be established on each device, except CGSs. The egress of the BGP LSP to be established needs to assign an MPLS label to the route advertised to an upstream node. If a transit node receives a labeled IPv4 route from downstream, the downstream node must re-assign an MPLS label to the transit node.
Configure an MP-EBGP peer relationship between an AGG and MASG to allow these devices to exchange VPNv4 route information.
Configure an MP-IBGP peer relationship between an CSG and AGG to allow these devices to exchange VPNv4 route information.
Configure VPN instances on each CSG, AGG, and MASG.
Configure a default route and an IP address prefix list on each AGG so that the AGG only advertises the default route to its directly connected CSG.

Data Preparation

To complete the configuration, you need the following data:

OSPF process ID (1) at the access layer, IS-IS process ID (1) at the aggregation layer, and OSPF process ID (2) at the core layer
MPLS LSR IDs: 1.1.1.1 for the CSG, 2.2.2.2 for the AGG, 3.3.3.3 for the AGG ASBR, 4.4.4.4 for the core ASBR, and 5.5.5.5 for the MASG.
Name of a routing policy (policy1)

Procedure

Assign an IP address to each interface.

Assign an IP address and its mask to every physical interface; configure a loopback interface address as an LSR ID on every device shown in Figure 2; configure OSPF and IS-IS to advertise the route to the network segment of each interface and a host route to each loopback interface address (LSR ID). For configuration details, see Configuration Files in this section.

Enable MPLS and LDP globally on each device.

# Configure the CSG.

[~CSG] mpls lsr-id 1.1.1.1

[*CSG] mpls

[*CSG-mpls] quit

[*CSG] mpls ldp

[*CSG-mpls-ldp] quit

[*CSG] interface GigabitEthernet 0/1/0

[*CSG-GigabitEthernet0/1/0] mpls

[*CSG-GigabitEthernet0/1/0] mpls ldp

[*CSG-GigabitEthernet0/1/0] quit

[*CSG] commit

# Configure the AGG.

[~AGG] mpls lsr-id 2.2.2.2

[*AGG] mpls

[*AGG-mpls] quit

[*AGG] mpls ldp

[*AGG-mpls-ldp] quit

[*AGG] interface GigabitEthernet 0/1/0

[*AGG-GigabitEthernet0/1/0] mpls

[*AGG-GigabitEthernet0/1/0] mpls ldp

[*AGG-GigabitEthernet0/1/0] quit

[*AGG] interface GigabitEthernet 0/2/0

[*AGG-GigabitEthernet0/2/0] mpls

[*AGG-GigabitEthernet0/2/0] mpls ldp

[*AGG-GigabitEthernet0/2/0] quit

[*AGG] commt

# Configure the AGG ASBR.

[~AGG ASBR] mpls lsr-id 3.3.3.3

[*AGG ASBR] mpls

[*AGG ASBR-mpls] quit

[*AGG ASBR] mpls ldp

[*AGG ASBR-mpls-ldp] quit

[*AGG ASBR] interface GigabitEthernet 0/1/0

[*AGG ASBR-GigabitEthernet0/1/0] mpls

[*AGG ASBR-GigabitEthernet0/1/0] mpls ldp

[*AGG ASBR-GigabitEthernet0/1/0] quit

[*AGG ASBR] commit

# Configure the core ASBR.

[~Core ASBR] mpls lsr-id 4.4.4.4

[*Core ASBR] mpls

[*Core ASBR-mpls] quit

[*Core ASBR] mpls ldp

[*Core ASBR-mpls-ldp] quit

[*Core ASBR] interface GigabitEthernet 0/2/0

[*Core ASBR-GigabitEthernet0/2/0] mpls

[*Core ASBR-GigabitEthernet0/2/0] mpls ldp

[*Core ASBR-GigabitEthernet0/2/0] quit

[*Core ASBR] commit

# Configure the MASG.

[~MASG] mpls lsr-id 5.5.5.5

[*MASG] mpls

[*MASG-mpls] quit

[*MASG] mpls ldp

[*MASG-mpls-ldp] quit

[*MASG] interface GigabitEthernet 0/1/0

[*MASG-GigabitEthernet0/1/0] mpls

[*MASG-GigabitEthernet0/1/0] mpls ldp

[*MASG-GigabitEthernet0/1/0] quit

[*MASG] commit

Establish IBGP peer relationships at the aggregation and core layers and enable devices to exchange labeled routes.

# Configure the AGG.

[~AGG] bgp 100

[*AGG-bgp] peer 3.3.3.3 as-number 100

[*AGG-bgp] peer 3.3.3.3 connect-interface LoopBack 1

[*AGG-bgp] peer 3.3.3.3 label-route-capability

[*AGG-bgp] network 2.2.2.2 32

[*AGG-bgp] quit

[*AGG] commit

# Configure the AGG ASBR.

[~AGG ASBR] bgp 100

[*AGG ASBR-bgp] peer 2.2.2.2 as-number 100

[*AGG ASBR-bgp] peer 2.2.2.2 connect-interface LoopBack 1

[*AGG ASBR-bgp] peer 2.2.2.2 label-route-capability

[*AGG ASBR-bgp] quit

[*AGG ASBR] commit

# Configure the core ASBR.

[~Core ASBR] bgp 200

[*Core ASBR-bgp] peer 5.5.5.5 as-number 200

[*Core ASBR-bgp] peer 5.5.5.5 connect-interface LoopBack 1

[*Core ASBR-bgp] peer 5.5.5.5 label-route-capability

[*Core ASBR-bgp] quit

[*Core ASBR] commit

# Configure the MASG.

[~MASG] bgp 200

[*MASG-bgp] peer 4.4.4.4 as-number 200

[*MASG-bgp] peer 4.4.4.4 connect-interface LoopBack 1

[*MASG-bgp] peer 4.4.4.4 label-route-capability

[*MASG-bgp] network 5.5.5.5 32

[*MASG-bgp] quit

[*MASG] commit

Establish an EBGP peer relationship between each pair of an AGG ASBR and core ASBR and enable these devices to exchange labeled routes.

# Configure the AGG ASBR.

[~AGG ASBR] interface GigabitEthernet 0/2/0

[~AGG ASBR-GigabitEthernet0/2/0] ip address 20.3.1.1 24

[*AGG ASBR-GigabitEthernet0/2/0] mpls

[*AGG ASBR-GigabitEthernet0/2/0] quit

[*AGG ASBR] bgp 100

[*AGG ASBR-bgp] peer 20.3.1.2 as-number 200

[*AGG ASBR-bgp] peer 20.3.1.2 label-route-capability check-tunnel-reachable

[*AGG ASBR-bgp] quit

[*AGG ASBR] commit

# Configure the core ASBR.

[~Core ASBR] interface GigabitEthernet 0/1/0

[~Core ASBR-GigabitEthernet0/1/0] ip address 20.3.1.2 24

[*Core ASBR-GigabitEthernet0/1/0] mpls

[*Core ASBR-GigabitEthernet0/1/0] quit

[*Core ASBR] bgp 200

[*Core ASBR-bgp] peer 20.3.1.1 as-number 100

[*Core ASBR-bgp] peer 20.3.1.1 label-route-capability check-tunnel-reachable

[*Core ASBR-bgp] quit

[*Core ASBR] commit

Configure an MP-EBGP peer relationship between each pair of an AGG and MASG.

# Configure the AGG.

[~AGG] bgp 100

[~AGG-bgp] peer 5.5.5.5 as-number 200

[*AGG-bgp] peer 5.5.5.5 connect-interface LoopBack 1

[*AGG-bgp] peer 5.5.5.5 ebgp-max-hop 10

[*AGG-bgp] ipv4-family vpnv4

[*AGG-bgp-af-vpnv4] peer 5.5.5.5 enable

[*AGG-bgp-af-vpnv4] quit

[*AGG-bgp] quit

[*AGG] commit

# Configure the MASG.

[~MASG] bgp 200

[~MASG-bgp] peer 2.2.2.2 as-number 100

[*MASG-bgp] peer 2.2.2.2 connect-interface LoopBack 1

[*MASG-bgp] peer 2.2.2.2 ebgp-max-hop 10

[*MASG-bgp] ipv4-family vpnv4

[*MASG-bgp-af-vpnv4] peer 2.2.2.2 enable

[*MASG-bgp-af-vpnv4] quit

[*MASG-bgp] quit

[*MASG] commit

Configure a routing policy to establish a BGP LSP.

# Configure a routing policy for advertising routes matching Route-Policy conditions to the AGG’s BGP peer.

<AGG> system-view

[~AGG] route-policy policy1 permit node 1

[*AGG-route-policy] apply mpls-label

[*AGG-route-policy] quit

[*AGG] bgp 100

[*AGG-bgp] peer 3.3.3.3 route-policy policy1 export

[*AGG-bgp] quit

[*AGG] commit

Repeat this step for the MASG. For configuration details, see Configuration Files in this section.

# Configure a routing policy for advertising routes matching Route-Policy conditions to the AGG ASBR’s BGP peer.

[~AGG ASBR] route-policy policy1 permit node 1

[*AGG ASBR-route-policy] if-match mpls-label

[*AGG ASBR-route-policy] apply mpls-label

[*AGG ASBR-route-policy] quit

[*AGG ASBR] bgp 100

[*AGG ASBR-bgp] peer 2.2.2.2 route-policy policy1 export

[*AGG ASBR-bgp] peer 20.3.1.2 route-policy policy1 export

[*AGG ASBR-bgp] quit

[*AGG ASBR] commit

Repeat this step for the core ASBR. For configuration details, see Configuration Files in this section.

After completing the preceding configurations, run the ping lsp command on an AGG or MASG. The command output shows that the AGG and MASG can ping each other. This indicates that the BGP LSP between the ASS and MASG has been established.

The following example uses the command output on the AGG.

<AGG> ping lsp bgp 5.5.5.5 32

  LSP PING FEC: BGP LABLED IPV4 PREFIX 5.5.5.5/32/ : 100  data bytes, press CTRL_C to break
    Reply from 5.5.5.5: bytes=100 Sequence=1 time=870 ms
    Reply from 5.5.5.5: bytes=100 Sequence=2 time=40 ms
    Reply from 5.5.5.5: bytes=100 Sequence=3 time=110 ms
    Reply from 5.5.5.5: bytes=100 Sequence=4 time=80 ms
    Reply from 5.5.5.5: bytes=100 Sequence=5 time=110 ms

  --- FEC: BGP LABLED IPV4 PREFIX 5.5.5.5/32 ping statistics ---
    5 packet(s) transmitted
    5 packet(s) received
    0.00% packet loss
    round-trip min/avg/max = 40/242/870 ms

Configure an MP-EBGP peer relationship between each pair of a CSG and MASG.

# Configure the CSG.

[~CSG] bgp 100

[~CSG-bgp] peer 2.2.2.2 as-number 100

[*CSG-bgp] peer 2.2.2.2 connect-interface LoopBack 1

[*CSG-bgp] network 1.1.1.1 32

[*CSG-bgp] ipv4-family vpnv4

[*CSG-bgp-af-vpnv4] peer 2.2.2.2 enable

[*CSG-bgp-af-vpnv4] quit

[*CSG-bgp] quit

[*CSG] commit

# Configure the AGG.

[~AGG] bgp 100

[~AGG-bgp] peer 1.1.1.1 as-number 100

[*AGG-bgp] peer 1.1.1.1 connect-interface LoopBack 1

[*AGG-bgp] ipv4-family vpnv4

[*AGG-bgp-af-vpnv4] peer 1.1.1.1 enable

[*AGG-bgp] quit

[*AGG] commit

Configure a VPN instance and bind an interface of each device to the VPN instance.

# Configure the CSG.

[~CSG] ip vpn-instance vpn1

[*CSG-vpn-instance-vpn1] ipv4-family

[*CSG-vpn-instance-vpn1-af-ipv4] route-distinguisher 100:1

[*CSG-vpn-instance-vpn1-af-ipv4] vpn-target 1:1

[*CSG-vpn-instance-vpn1-af-ipv4] quit

[*CSG-vpn-instance-vpn1] quit

[*CSG] interface GigabitEthernet 0/2/0

[*CSG-GigabitEthernet0/2/0] ip binding vpn-instance vpn1

[*CSG-GigabitEthernet0/2/0] ip address 10.1.1.1 255.255.255.0

[*CSG-GigabitEthernet0/2/0] quit

[*CSG] bgp 100

[*CSG-bgp] ipv4-family vpn-instance vpn1

[*CSG-bgp-vpn1] import-route direct

[*CSG-bgp-vpn1] quit

[*CSG-bgp] quit

[*CSG] commit

[~CSG] quit

Repeat this step for the MASG. For configuration details, see Configuration Files in this section.

# Configure the AGG.

[~AGG] ip vpn-instance vpn1

[*AGG-vpn-instance-vpn1] ipv4-family

[*AGG-vpn-instance-vpn1-af-ipv4] route-distinguisher 100:1

[*AGG-vpn-instance-vpn1-af-ipv4] vpn-target 1:1

[*AGG-vpn-instance-vpn1-af-ipv4] quit

[*AGG-vpn-instance-vpn1] quit

[*AGG] commit

Configure a default route and an IP address prefix list on each AGG so that the AGG only advertises the default route to its directly connected CSG.

[~AGG] ip route-static vpn-instance vpn1 0.0.0.0 0.0.0.0 NULL0

[*AGG] ip ip-prefix default index 10 permit 0.0.0.0 0

[*AGG] bgp 100

[*AGG-bgp] ipv4-family vpnv4

[*AGG-bgp-af-vpnv4] peer 1.1.1.1 ip-prefix default export

[*AGG-bgp-af-vpnv4] quit

[*AGG-bgp] ipv4-family vpn-instance vpn1

[*AGG-bgp-vpn1] network 0.0.0.0 0

[*AGG-bgp-vpn1] quit

[*AGG-bgp] quit

[*AGG] commit

Verify the configuration.

After completing the preceding configurations, run the display ip routing-table command on the CSG. The command output shows that the CSG has a default route with its directly connected AGG as the next hop, but does not have a VPN route to the MME or SGW. In addition, the CSG can ping the MME or SGW.

The following example uses the command output on the CSG.

<CSG> display ip routing-table vpn-instance vpn1

Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Routing Table : vpn1
         Destinations : 5        Routes : 5

Destination/Mask    Proto   Pre  Cost        Flags NextHop         Interface

        0.0.0.0/0   IBGP    255  0             RD 2.2.2.2         LDP LSP
       10.1.1.0/24  Direct  0    0             D  10.1.1.1        GigabitEthernet0/2/0
       10.1.1.1/32  Direct  0    0             D  127.0.0.1       GigabitEthernet0/2/0
     10.1.1.255/32  Direct  0    0             D  127.0.0.1       GigabitEthernet0/2/0
255.255.255.255/32  Direct  0    0             D  127.0.0.1       InLoopBack0

<CSG> ping -vpn-instance vpn1 10.2.1.1

  PING 10.2.1.0: 56  data bytes, press CTRL_C to break
    Reply from 10.2.1.0: bytes=56 Sequence=1 ttl=252 time=6 ms
    Reply from 10.2.1.0: bytes=56 Sequence=2 ttl=252 time=3 ms
    Reply from 10.2.1.0: bytes=56 Sequence=3 ttl=252 time=3 ms
    Reply from 10.2.1.0: bytes=56 Sequence=4 ttl=252 time=4 ms
    Reply from 10.2.1.0: bytes=56 Sequence=5 ttl=252 time=2 ms

  --- 10.2.1.1 ping statistics ---
    5 packet(s) transmitted
    5 packet(s) received
    0.00% packet loss
    round-trip min/avg/max = 2/3/6 ms

Configuration Files

CSG configuration file

#
sysname CSG
#
ip vpn-instance vpn1
 ipv4-family
  route-distinguisher 100:1
  vpn-target 1:1 export-extcommunity
  vpn-target 1:1 import-extcommunity
#
mpls lsr-id 1.1.1.1
#
mpls
#
mpls ldp
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 20.1.1.1 255.255.255.0
 mpls
 mpls ldp
#
interface GigabitEthernet0/2/0
 undo shutdown
 ip binding vpn-instance vpn1
 ip address 10.1.1.1 255.255.255.0
#
interface LoopBack1
 ip address 1.1.1.1 255.255.255.255
#
bgp 100
 peer 2.2.2.2 as-number 100
 peer 2.2.2.2 connect-interface LoopBack1
 #
 ipv4-family unicast
  undo synchronization
  peer 2.2.2.2 enable
 #
 ipv4-family vpnv4
  policy vpn-target
  peer 2.2.2.2 enable
 #
 ipv4-family vpn-instance vpn1
  import-route direct
#
ospf 1
 area 0.0.0.0
  network 1.1.1.1 0.0.0.0
  network 20.1.1.0 0.0.0.255
#
route-policy policy1 permit node 1
 apply mpls-label
#
return

AGG configuration file

#
sysname AGG
#
ip vpn-instance vpn1
 ipv4-family
  route-distinguisher 100:1
  vpn-target 1:1 export-extcommunity
  vpn-target 1:1 import-extcommunity
#
mpls lsr-id 2.2.2.2
#
mpls
#
mpls ldp
#
isis 1
 network-entity 10.0000.0000.0000.0010.00
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 20.1.1.2 255.255.255.0
 mpls
 mpls ldp
#
interface GigabitEthernet0/2/0
 undo shutdown
 ip address 20.2.1.1 255.255.255.0
 isis enable 1
 mpls
 mpls ldp
#
interface LoopBack1
 ip address 2.2.2.2 255.255.255.255
 isis enable 1
#
bgp 100
 peer 1.1.1.1 as-number 100
 peer 1.1.1.1 connect-interface LoopBack1
 peer 3.3.3.3 as-number 100
 peer 3.3.3.3 connect-interface LoopBack1
 peer 5.5.5.5 as-number 200
 peer 5.5.5.5 ebgp-max-hop 10
 peer 5.5.5.5 connect-interface LoopBack1
 #
 ipv4-family unicast
  undo synchronization
  network 2.2.2.2 255.255.255.255
  peer 1.1.1.1 enable
  peer 3.3.3.3 enable
  peer 3.3.3.3 route-policy policy1 export
  peer 3.3.3.3 label-route-capability
  peer 5.5.5.5 enable
 #
 ipv4-family vpnv4
  policy vpn-target
  peer 1.1.1.1 enable
  peer 1.1.1.1 ip-prefix default export
  peer 5.5.5.5 enable
 #
 ipv4-family vpn-instance vpn1
  network 0.0.0.0
#
ospf 1
 area 0.0.0.0
  network 2.2.2.2 0.0.0.0
  network 20.1.1.0 0.0.0.255
#
route-policy policy1 permit node 1
 apply mpls-label
#
ip ip-prefix default index 10 permit 0.0.0.0 0
#
ip route-static vpn-instance vpn1 0.0.0.0 0.0.0.0 NULL0
#
return

AGG ASBR configuration file

#
sysname AGG ASBR
#
mpls lsr-id 3.3.3.3
#
mpls
#
mpls ldp
#
isis 1
 network-entity 10.0000.0000.0000.0020.00
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 20.2.1.2 255.255.255.0
 isis enable 1
 mpls
 mpls ldp
#
interface GigabitEthernet0/2/0
 undo shutdown
 ip address 20.3.1.1 255.255.255.0
 mpls
#
interface LoopBack1
 ip address 3.3.3.3 255.255.255.255
 isis enable 1
#
bgp 100
 peer 2.2.2.2 as-number 100
 peer 2.2.2.2 connect-interface LoopBack1
 peer 20.3.1.2 as-number 200
 #
 ipv4-family unicast
  undo synchronization
  peer 2.2.2.2 enable
  peer 2.2.2.2 route-policy policy1 export
  peer 2.2.2.2 label-route-capability
  peer 20.3.1.2 enable
  peer 20.3.1.2 route-policy policy1 export
  peer 20.3.1.2 label-route-capability check-tunnel-reachable
#
route-policy policy1 permit node 1
 if-match mpls-label
 apply mpls-label
#
return

Core ASBR configuration file

#
sysname Core ASBR
#
mpls lsr-id 4.4.4.4
#
mpls
#
mpls ldp
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip address 20.3.1.2 255.255.255.0
 mpls
#
interface GigabitEthernet0/2/0
 undo shutdown
 ip address 20.4.1.1 255.255.255.0
 mpls
 mpls ldp
#
interface LoopBack1
 ip address 4.4.4.4 255.255.255.255
#
bgp 200
 peer 5.5.5.5 as-number 200
 peer 5.5.5.5 connect-interface LoopBack1
 peer 20.3.1.1 as-number 100
 #
 ipv4-family unicast
  undo synchronization
  peer 5.5.5.5 enable
  peer 5.5.5.5 route-policy policy1 export
  peer 5.5.5.5 label-route-capability
  peer 20.3.1.1 enable
  peer 20.3.1.1 route-policy policy1 export
  peer 20.3.1.1 label-route-capability check-tunnel-reachable
#
ospf 2
 area 0.0.0.0
  network 4.4.4.4 0.0.0.0
  network 20.4.1.0 0.0.0.255
#
route-policy policy1 permit node 1
 if-match mpls-label
 apply mpls-label
#
return

MASG configuration file

#
sysname MASG
#
ip vpn-instance vpn1
 ipv4-family
  route-distinguisher 100:1
  vpn-target 1:1 export-extcommunity
  vpn-target 1:1 import-extcommunity
#
mpls lsr-id 5.5.5.5
#
mpls
#
mpls ldp
#
interface GigabitEthernet0/1/0
 undo shutdown
 ip binding vpn-instance vpn1
 ip address 10.2.1.1 255.255.255.0
#
interface GigabitEthernet0/2/0
 undo shutdown
 ip address 20.4.1.2 255.255.255.0
 mpls
 mpls ldp
#
interface LoopBack1
 ip address 5.5.5.5 255.255.255.255
#
bgp 200
 peer 2.2.2.2 as-number 100
 peer 2.2.2.2 ebgp-max-hop 10
 peer 2.2.2.2 connect-interface LoopBack1
 peer 4.4.4.4 as-number 200
 peer 4.4.4.4 connect-interface LoopBack1
 #
 ipv4-family unicast
  undo synchronization
  network 5.5.5.5 255.255.255.255
  peer 2.2.2.2 enable
  peer 4.4.4.4 enable
  peer 4.4.4.4 route-policy policy1 export
  peer 4.4.4.4 label-route-capability
 #
 ipv4-family vpnv4
  policy vpn-target
  peer 2.2.2.2 enable
 #
 ipv4-family vpn-instance vpn1
  import-route direct
#
ospf 2
 area 0.0.0.0
  network 5.5.5.5 0.0.0.0
  network 20.4.1.0 0.0.0.255
#
route-policy policy1 permit node 1
 apply mpls-label
#
return

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Networking Requirements

Configuration Roadmap

Data Preparation

Procedure

Configuration Files

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