Example for Configuring Centralized MAP-E

This section provides an example for configuring the centralized MAP-E function on the device that functions as a MAP BR.

Networking Requirements

In a centralized scenario shown in Figure 1, the MAP-BR and BRAS reside on different devices. The BRAS delivers MAP addresses and mapping rules to MAP-CEs in DHCPv6 IA_PD mode. Router A resides on the edge of a MAP domain and allows MAP-CEs to access the public IPv4 network through the IPv6 network that is within the MAP domain. The MAP-CEs use each other's public IPv4 address to communicate through the MAP-BR.

Figure 1 Networking diagram for configuring MAP-E

In this example, interface 1 and interface 2 are GE 0/1/8 and GE 0/1/9, respectively.

Prerequisites

The MAP function has been activated.
The MAP-BR has at least one interface board that supports the MAP function.

Configuration Roadmap

The configuration roadmap is as follows:

Configure a BR.
Configure BMR rules.
Configure a MAP-E instance and bind the BMR and BR rules to the MAP-E instance.
Configure an IPv6 prefix pool and an address pool on the BRAS.
Configure the IP address for each interface and a static route.

Data Preparation

To complete the configuration, you need the following data:

BR name (br_name), IPv6 address (2001:db8:1124::1), and prefix length (96 bits)
BMR name (bmr_name), IPv6 address (2001:db8:1::1), prefix length (48), IPv4 address (1.1.1.0), mask length (24), EA-length (16), and PSID-offset length (4)
MAP-E instance name (2) and ID (2)
Interface1's IPv6 address (2001:db8:2::1) and mask length (64 bits).
Interface2's IPv4 address (11.1.1.1) and mask length (24 bits)

Procedure

Configure the BR function on a BRAS named br_name and set the IPv6 address to 2001:db8:1124::1 and the prefix length to 96. Use the BR's IPv6 address as the destination address carried in packets sent by MAP-CEs.
```
<BRAS> system-view
[~BRAS] br-ipv6-address br_name ipv6-address 2001:db8:1124::1 prefix-length 96
[*BRAS] commit
```
Configure a BMR on the BRAS to instruct the BRAS to assign IPv6 and IPv4 addresses to the MAP-CEs. In this example, the IPv6 prefix address assigned to the MAP-CE is 2001:db8:1::1, the prefix length is 48, and the length of the EA-bits is 16. The public IPv4 prefix address allocated to the MAP-CE is 1.1.1.0 and the prefix length is 24. The offset length of the PSID field is 4, which means that ports 0 to 4096 are reserved.
```
[~BRAS] map rule bmr_name
[*BRAS-map-rule-bmr_name] rule-prefix 2001:db8:1::1 prefix-length 48 ipv4-prefix 1.1.1.0 prefix-length 24 ea-length 16 psid-offset 4
[*BRAS-map-rule-bmr_name] commit
[~BRAS-map-rule-bmr_name] quit
```
Configure an IPv6 prefix pool and an address pool on the BRAS.
- Configure an IPv6 prefix pool named pre1 and bind it to the BMR rule named bmr_name to allocate PD prefixes to MAP-CEs.
```
[~BRAS] ipv6 prefix pre1 delegation
[*BRAS-ipv6-prefix-pre1] map-rule bmr_name
[*BRAS-ipv6-prefix-pre1] commit
[~BRAS-ipv6-prefix-pre1] quit
```
- Configure an IPv6 address pool named pool1 and bind it to the prefix pool named pre1. Bind the BR name br_name to the IPv6 address pool. Then, the BRAS encapsulates the IPv6 prefix into Option 90 information (OPTION_S46_BR) carried in the IPv6 prefix into the DHCPv6 RESPONSE message sent to MAP-CEs.
```
<BRAS> system-view
[~BRAS] ipv6 pool pool1 bas delegation
[*BRAS-ipv6-pool-pool1] prefix pre1
[*BRAS-ipv6-pool-pool1] option-s46 br-ipv6-address br_name
[*BRAS-ipv6-pool-pool1] commit
[~BRAS-ipv6-pool-pool1] quit
```
On the MAP-BR, configure the BR that is the local IPv6 address as the destination address of IPv6 packets sent by MAP-CEs. Set the BR name to br_name, the IPv6 address to 2001:db8:1124::1, and the prefix length to 96.
```
<RouterA> system-view
[~RouterA] br-ipv6-address br_name ipv6-address 2001:db8:1124::1 prefix-length 96
[*RouterA] commit
```

Configure BMRs on the MAP-BR. Configure the BMR to remove the user-side IPv4 address from the IPv6 address and encapsulate IPv6 information into the IPv4 address and port number of the network-side traffic.

[~RouterA] map rule bmr_name
[*RouterA-map-rule-bmr_name] rule-prefix 2001:db8:1::1 prefix-length 48 ipv4-prefix 1.1.1.0 prefix-length 24 ea-length 16 psid-offset 4
[*RouterA-map-rule-bmr_name] commit
[~RouterA-map-rule-bmr_name] quit

Configure a MAP-E instance on the MAP-BR and bind the configured BR and BMR rules to the MAP-E instance. The BR is used to import the encapsulated traffic of MAP-CEs to an interface board, select the MAP-E instance for conversion, and bind the BMR rule to encapsulate and verify the packets in the instance.
```
[~RouterA] map-e instance 2 id 2
[*RouterA-map-e-instance-2] br-ipv6-address br_name
[*RouterA-map-e-instance-2] map-rule bmr_name
[*RouterA-map-e-instance-2] commit
[~RouterA-map-e-instance-2] quit
```

Configure IP addresses of the user- and network-side interfaces on the MAP-BR.

[~RouterA] interface GigabitEthernet0/1/8
[~RouterA-GigabitEthernet0/1/8] ipv6 enable
[*RouterA-GigabitEthernet0/1/8] ipv6 address 2001:db8:2::1 64
[*RouterA-GigabitEthernet0/1/8] commit
[~RouterA-GigabitEthernet0/1/8] quit
[~RouterA] interface GigabitEthernet0/1/9
[~RouterA-GigabitEthernet0/1/9] ip address 11.1.1.1 24
[*RouterA-GigabitEthernet0/1/9] commit
[~RouterA-GigabitEthernet0/1/9] quit
[~RouterA] ipv6 route-static 2001:db8:1::1 48 2001:db8:2::2
[*RouterA] commit

Configure an address for the interface connecting the BRAS to the MAP-BR device.

[~BRAS] interface GigabitEthernet0/1/8
[*BRAS-GigabitEthernet0/1/8] ipv6 enable
[*BRAS-GigabitEthernet0/1/8] ipv6 address 2001:db8:2::2 64
[*BRAS-GigabitEthernet0/1/8] undo shutdown
[*BRAS-GigabitEthernet0/1/8] commit
[~BRAS] ipv6 route-static 2001:db8:1124::1 64 2001:db8:2::1
[*BRAS] commit

Router A Configuration File (MAP-BR)

#
br-ipv6-address br_name ipv6-address 2001:db8:1124::1 prefix-length 96
#
map rule bmr_name
 rule-prefix 2001:db8:1::1 prefix-length 48 ipv4-prefix 1.1.1.0 prefix-length 24 ea-length 16 psid-offset 4
#
map-e instance 2 id 2
 br-ipv6-address br_name
 map-rule bmr_name
#
interface GigabitEthernet0/1/8
 undo negotiation auto
 undo shutdown
 ipv6 enable
 ipv6 address 2001:db8:2::/64
#
interface GigabitEthernet0/1/9
 undo negotiation auto
 undo shutdown
 control-flap
 ip address 11.1.1.1 255.255.255.0
#
ipv6 route-static 2001:db8:1::1 48 2001:db8:2::2
#

BRAS Configuration File

#
br-ipv6-address br_name ipv6-address 2001:db8:1124::1 prefix-length 96
#
map rule bmr_name
 rule-prefix 2001:db8:1::1 prefix-length 48 ipv4-prefix 1.1.1.0 prefix-length 24 ea-length 16 psid-offset 4
#
ipv6 prefix pre1 delegation
 map-rule bmr_name
ipv6 pool pool1 bas delegation
 prefix pre1
 option-s46 br-ipv6-address br_name
#
interface GigabitEthernet0/1/8
 undo shutdown
 ipv6 enable
 ipv6 address 2001:db8:2::2/64
#
ipv6 route-static 2001:db8:1124::1 64 2001:db8:2::1
#