Cisco Systems 3560 Manual De Usuario

If any of the upstream interfaces are in the link-up state, the downstream interfaces can change to 
or remain in the link-up state.

If all of the upstream interfaces become unavailable, link-state tracking automatically puts the 
downstream interfaces in the error-disabled state. Connectivity to and from the servers is 
automatically changed from the primary server interface to the secondary server interface. 

As an example of a connectivity change from link-state group 1 to link-state group 2 on switch A, 
see 

. If the upstream link for port 6 is lost, the link states of downstream 

ports 1 and 2 do not change. However, if the link for upstream port 5 is also lost, the link state of the 
downstream ports changes to the link-down state. Connectivity to server 1 and server 2 is then 
changed from link-state group1 to link-state group 2. The downstream ports 3 and 4 do not change 
state because they are in link-group 2.

If the link-state group is configured, link-state tracking is disabled, and the upstream interfaces lose 
connectivity, the link states of the downstream interfaces remain unchanged. The server does not 
recognize that upstream connectivity has been lost and does not failover to the secondary interface. 

You can recover a downstream interface link-down condition by removing the failed downstream port 
from the link-state group. To recover multiple downstream interfaces, disable the link-state group.