以太通道 链路聚合.ppt

以太通道（EtherChannel） 以太通道（EtherChannel）的动态协商协议 以太通道配置命令 配置二层以太通道（L2 EtherChannel） EtherChannel指导原则 若通过PAgP或LACP进行动态协商，需要满足以下条件： 1）vlan特性 (access/trunk) 2）trunk特性 (fa0/1:vlan 1-10, fa0/2:vlan1-5) 3）速率 (10M/100M) 4）双工模式 (半双工/全双工) 配置三层以太通道（L3 EtherChannel） 查看EtherChannel 查看EtherChannel(续) 以太通道配置实例 总结 When the EtherChannel becomes one entity, the traffic is load balanced across multiple links. This subsection describes the configuration of load balancing among the ports included in an EtherChannel. Load balancing traffic across port members of the same EtherChannel is a key element in an EtherChannel configuration. As shown in the figure, two workstations communicate with a router through a switch. The link between the router and the switch is an EtherChannel link relying on two physical ports. Suppose that the majority of the traffic is going from the PCs toward the router. How should the traffic be load balanced across the two physical links? If load balancing is based on the destination IP address, most traffic will go through the same physical link. Because the router has only one single IP address for its bundled interface, this IP address will be associated to a first physical port, and all traffic destined to it will go through a single physical link. This renders the load-balancing mechanism inefficient. On the other hand, if load balancing is based on the source MAC address, the traffic might be far better balanced across both physical links because each PC has its MAC address seen on the switch. As a rule, use the load-balancing option that provides the greatest variety in your configuration. For example, if the traffic on a channel is going to only a single MAC address, using the destination-MAC address always chooses the same link in the channel; using source addresses might result in better load balancing. Note: EtherChannel balances traffic load across the links in a channel. The default and the load balancing methods available can vary among