Configuring Link Aggregation Control Protocol Hot-Standby Ports When LACP is enabled, the software, by default, tries to configure the maximum number of LACP-compatible ports in a channel, up to a maximum of 16 ports. Only eight LACP links can be active at one time; the remaining eight links are placed in hot-standby mode. If one of the active links becomes inactive, a link that is in the hot-standby mode becomes active in its place. You can override the default behavior by specifying the maximum number of active ports in a channel, in which case, the remaining ports become hot-standby ports.
For example, if you specify a maximum of five ports in a channel, up to 11 ports become hot-standby ports. Configuring EtherChannels Configuring Link Aggregation Control Protocol Hot-Standby Ports Command or Action Purpose Step 2 configure terminal Example: Device# configure terminal Enters global configuration mode. Step 3 interface interface-id Example: Device(config)# interface gigabitethernet 1/0/2 Specifies the port for transmission, and enters interface configuration mode. Step 4 pagp learn-method physical-port Example: Device(config-if)# pagp learn-method physical port Selects the PAgP learning method.
By default, aggregation-port learning is selected, which means the device sends packets to the source by using any of the ports in the EtherChannel. With aggregate-port learning, it is not important on which physical port the packet arrives. Selects physical-port to connect with another device that is a physical learner. Make sure to configure the port-channel load-balance global configuration command to src-mac. The learning method must be configured the same at both ends of the link. Step 5 pagp port-priority priority Example: Device(config-if)# pagp port-priority 200 Assigns a priority so that the selected port is chosen for packet transmission. For priority, the range is 0 to 255.
The default is 128. The higher the priority, the more likely that the port will be used for PAgP transmission. Step 6 end Example: Device(config-if)# end Returns to privileged EXEC mode. Configuring EtherChannels 20