R0106-HP MSR Router Series MPLS Configuration Guide(V7)

Configure LDP to establish LSPs only on the link Router A—Router B—Router C to forward traffic between

subnets 11.1.1.0 / 24 a n d 21.1.1.0 / 24 .

Figure 19 Network diagram

Requirements analysis

• To ensure that the LSRs establish LSPs automatically, enable LDP on each LSR.

• To establish LDP LSPs, configure a routing protocol to ensure IP connectivity between the LSRs. This

example uses OSPF.

• To ensure that LDP establishes LSPs only for the routes 11.1.1.0 / 24 a n d 21.1.1.0 / 24, c o n f ig u r e L SP

generation policies on each LSR.

• To ensure that LDP establishes LSPs only over the link Router A—Router B—Router C, configure label

advertisement policies as follows:

{ Router A advertises only the label mapping for FEC 11.1.1.0 / 24 t o Ro u t er B .

{ Router C advertises only the label mapping for FEC 21.1.1.0/24 to Router B.

{ Router D does not advertise label mapping for FEC 21.1.1.0/24 to Router A. Router D does not

advertise label mapping for FEC 11.1.1.0 / 24 t o R o ut e r C .

Configuration procedure

1. Configure IP addresses and masks for interfaces, including the loopback interfaces, as shown

in Figure 19. (Details not sh

own.)

2. Configure OSPF on each router to ensure IP connectivity between them. (Details not shown.)

3. Enable MPLS and LDP:

# Configure Router A.

<RouterA> system-view

[RouterA] mpls lsr-id 1.1.1.9

[RouterA] mpls ldp

[RouterA-ldp] quit

[RouterA] interface serial 2/1/0

[RouterA-Serial2/1/0] mpls enable

[RouterA-Serial2/1/0] mpls ldp enable

[RouterA-Serial2/1/0] quit