multicast load-splitting
Function
The multicast load-splitting command enables load splitting among multicast routes.
The undo multicast load-splitting command restores the default configuration.
Format
multicast load-splitting { balance-preferred | stable-preferred | group | source | source-group }
undo multicast load-splitting
Parameters
| Parameter | Description | Value |
|---|---|---|
| balance-preferred | Indicates balance-preferred load splitting. This policy is applicable to the scenario where hosts frequently join or leave groups, which requires automatic load adjustment. | - |
| stable-preferred | Indicates stable-preferred load splitting. This policy is applicable to stable multicast networking. | - |
| group | Indicates group address-based load splitting. This policy is applicable to the scenario of one source to multiple groups. | - |
| source | Indicates source address-based load splitting. This policy is applicable to the scenario of multiple sources to one group. | - |
| source-group | Indicates source and group addresses-based load splitting. This policy is applicable to the scenario of multiple sources to multiple groups. | - |
Usage Guidelines
By default, load splitting among multicast routes is disabled.
If multiple equal-cost routes exist over the network, you can run the multicast load-splitting command to realize load splitting among the equal-cost routes. The FW determines the routing table for creating multicast routing entries based on the mask lengths and preferences of routes. All equal cost routes in the determined routing table can then take part in load splitting. The FW supports load splitting among the routes in a single routing table.
If balance-preferred or stable-preferred is specified, the FW runs the load splitting algorithm based on the actual network status and splits (*, G) and (S, G) entries into the corresponding equal-cost routes to achieve load splitting.
If balance-preferred is specified, the FW automatically adjusts and balances the entries on the equal-cost routes when equal-cost routes are added or deleted, multicast routing entries are deleted, or load splitting weights on the interfaces are changed.
If stable-preferred is specified, the FW automatically adjusts and balances the entries when equal-cost routes are added or deleted. However, when multicast routing entries are deleted or load splitting weights on the interfaces are changed, the FW does not automatically adjust the entries on the equal-cost routes.
The default value of a multicast load splitting timer is 1800 seconds. To specify the value of a multicast load splitting timer, run the multicast load-splitting-timer command. To prevent multicast route flapping, do not set the value to a very small value. The multicast load-splitting-timer command applies to stable-preferred and balance-preferred load splitting scenarios.
If group, source, or source-group is specified, fixed algorithms are used for load splitting. When multicast routing entries and network configurations are stable, Reverse Path Forwarding (RPF) interfaces and RPF neighbors stay unchanged.
Adopt a fixed multicast load splitting policy based on actual networking. The balance-preferred or stable-preferred policy is preferred.
Because the forwarding capabilities of equal-cost routes are different from the actual load bearing situation on the equal-cost routes, even load splitting cannot meet network requirements in some scenarios. Then, you can run the multicast load-splitting weight command to configure the multicast load splitting weight on the interface to realize unbalanced load splitting.
You must run the multicast routing-enable command to enable the multicast function before using the command.
balance-preferred or stable-preferred cannot be configured on an interface enabled with PIM-DM.
Example
<sysname> system-view [sysname] multicast routing-enable [sysname] multicast load-splitting balance-preferred
<sysname> system-view
[sysname] multicast routing-enable
[sysname] ip vpn-instance mytest
[sysname-vpn-instance-mytest] ipv4-family
[sysname-vpn-instance-mytest-af-ipv4] multicast load-splitting balance-preferred