LACP Hot Standby
July 22, 2012 3 Comments
LACP allows for up to 16 ports to be configure to be part of a port channel but only 8 are active at any point in time and the others are in a hot standby state.
When one port fails the switch will choose a replacement from the hot standby pool. Priorities can be assigned such that some ports will be chosen to be a part of the port channel ahead of others.
LACP chooses port based on the following
- LACP system priority
- System ID (the switch MAC address)
- LACP port priority
- Port number
Note: with LACP numerically LOWER values have a HIGHER priority
Configuring LACP priorities
Configure System ID (default is 32768)
Switch(config)#lacp system-priority 1000
Switch(config)#do sh lacp sys-id
Configure LACP Port Priority (default is 32768)
Switch(config-if)#lacp port-priority 100
This would make this port more desirable than the other ports.