let'suppose we have more 3750 switch in one stack combination and only one uplink to connect the central switch in a star configuration, what happens in case the switch with uplink goes down? is the stack traffic blocked?
If the stack master fails, the entire stack would be isolated. Cross-Stack EtherChannel allows the aggregation of up to eight separate physical ports from multiple switches in the stack to form one logical channel uplink. This would provide enough diversity should the master or any member of the stack fail. You could also refer to the following document.
