Configuring UCMP
- Support not only routing UCMP, but also LSP/Tunnel UCMP which supports L2VPN and MPLS P scenarios.
- You are not advised to configure UCMP between WAN and LAN interfaces. If UCMP is configured between WAN and LAN interfaces (such as 10GE interfaces), a packet header overhead is generated because of SDH or SONET encapsulation during packet transmission on the WAN interface. As a result, the bandwidth ratio between the WAN and LAN interfaces is about 93:100. In this case, traffic is balanced among links based on the bandwidth ratio of 93:100. Therefore, the consumed forwarding resources increase to 193. If a large number of such scenarios occur, large amounts of forwarding resources are consumed, causing insufficient resources.
Routing UCMP can be deployed in two methods.
Method 1: Enable Routing UCMP globally
- Run system-view
The system view is displayed.
Run load-balance unequal-cost enable
UCMP is enabled globally.
By default, UCMP is not enabled in the system.
When the UCMP is enabled globally, the UCMP takes effect on Ethernet interfaces, Gigabit Ethernet interfaces, Eth-Trunk interfaces, and TE tunnel interfaces.
- Run commit
The configuration is committed.
Method 2: Enable UCMP on the interfaces
- Run system-view
The system view is displayed.
- Run interface interface-type interface-number
The interface view is displayed.
Run load-balance unequal-cost enable
UCMP is enabled on the interface.
This command cannot be enabled on logical interfaces. It can be enabled only on physical interfaces.
- Run shutdown and undo shutdown
The interface is restarted so that the UCMP configuration takes effect.
Routes and FIB entries are refreshed only when you restart the interface after UCMP is enabled or disabled on the interface.
- Run commit
The configuration is committed.
Enable UCMP for LSP/Tunnel
Views |
Command Format |
Function and Scenarios |
|---|---|---|
System view |
load-balance mpls unequal-cost enable |
Enables UCMP for LSPs on an MPLS P node (excluding BGP P nodes) If UCMP is enabled and the MPLS P nodes (excluding BGP P nodes) have multiple outbound interfaces, UCMP is performed among the outbound interfaces based on bandwidth weights. If UCMP is disabled and the MPLS P nodes have multiple outbound interfaces, ECMP is performed among the outbound interfaces. To enable UCMP for MPLS P nodes (excluding BGP P nodes), run the load-balance mpls unequal-cost enable command. In an SR-MPLS TE Policy scenario, you can also enable UCMP on the ingress of an SR-MPLS TE Policy. |
Follow-up Procedure
Run the save command to save the current configuration to the configuration file when a set of configuration is finished and the expected functions have been achieved.