Specifying an IPv6 VRRP control VLAN
VLAN termination enables an interface to remove the VLAN tags of a packet and deliver the packet to Layer 3 forwarding or other processing pipelines. The following VLAN termination categories are available:
Unambiguous termination—Terminates VLAN packets from a specified VLAN only. After receiving a packet from the VLAN, the interface that is configured with unambiguous VLAN termination removes its VLAN tag.
Ambiguous termination—Terminates VLAN packets from multiple VLANs whose VLAN IDs are in the specified range. After receiving a packet from a VLAN in the specified range, the interface that is configured with ambiguous VLAN termination removes its VLAN tag.
By default, an ambiguous termination-enabled Layer 3 subinterface drops broadcast and multicast packets that it receives. You can enable the interface to transmit broadcast packets and multicast packets as needed. The packets are transmitted within all VLANs whose VLAN packets are configured to be terminated by the subinterface.
Figure 22: IPv6 VRRP control VLAN
As shown in Figure 22, ambiguous VLAN termination is configured for VLAN 10 and VLAN 20 on the Layer 3 Ethernet subinterfaces on routers. To allow the master to regularly send IPv6 VRRP advertisements in multicast to the backups, enable the VLAN termination-enabled subinterfaces to transmit broadcast packets and multicast packets. Then, the master can send IPv6 VRRP advertisements within all VLANs whose VLAN packets are configured to be terminated by the subinterfaces. If ambiguous VLAN termination is configured on the Layer 3 Ethernet subinterfaces for a large range of VLANs, the IPv6 VRRP advertisements might overload the subinterfaces. This adversely affects the performance of the routers.
To solve this problem, perform the following tasks:
Disable the VLAN termination-enabled subinterfaces from transmitting broadcast packets and multicast packets.
Configure an IPv6 VRRP control VLAN to allow the master to send IPv6 VRRP advertisements only within the control VLAN.
The following categories of IPv6 VRRP control VLANs are available:
VLANs with a single VLAN tag—Specified for ambiguous Dot1q termination-enabled subinterfaces.
VLANs with both inner and outer VLAN tags—Specified for ambiguous QinQ termination-enabled subinterfaces.
For more information about VLAN termination, see Layer 2—LAN Switching Configuration Guide.
Configuration guidelines
When IPv6 VRRP is operating in load balancing mode, you cannot specify the IPv6 VRRP control VLAN.
Configuration procedure
To specify an IPv6 VRRP control VLAN:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Enter Layer 3 Ethernet subinterface view or Reth subinterface view. | interface interface-type interface-number | N/A |
3. Specify an IPv6 VRRP control VLAN. |
| By default, no IPv6 VRRP control VLAN is specified. The master sends IPv6 VRRP advertisements within all VLANs whose VLAN packets are configured to be terminated by the subinterface. |