(Optional) Enabling Next-Hop-based Label Allocation on the ASBR

To save label resources on an ASBR, you can enable next-hop-based label allocation on the ASBR. Note that next-hop-based label allocation and one label per instance need to be used together on the ASBR.

Context

In a VPN Option B scenario, after next-hop-based label allocation is enabled on the ASBR, the ASBR allocates only one label for the IPv4 VPN routes with the same next hop and outgoing label. Compared with allocating a label for each IPv4 VPN route, next-hop-based label allocation saves label resources.

Perform the following steps on the ASBR.

Procedure

Access the system view.
```
system-view
```
Access the BGP view.
```
bgp { as-number-plain | as-number-dot }
```
Access the BGP VPNv4 view.
```
ipv4-family vpnv4
```
Enable the next-hop-based label allocation for IPv4 VPN routes on the ASBR.
```
apply-label per-nexthop
```
After next-hop-based label allocation is enabled or disabled, the label allocated by the ASBR for a route changes, which leads to packet loss.