200 301 vs 200 125

200 301 vs 200 125.Number of channel-groups in use: 1 Number of aggregators:Group Port-channel Protocol PortsPol(SU) FaO/14(P) FaO/15(P)Take a moment to look at the output of the two show commands in the example. First, show spanning-treecommand lists the Pol interface, which is short for PortChannel1. Since the channel-group command uses parameter 1, this interface appears. STP no longer operates on the physical interfaces F0/14 and F0/15, but on the PortChannel1 interface, so only that interface appears in the output.Next, see the show etherchannel 1summary command. It is titled "Portchannel" and underneath it is Pol. In addition, F0/14 and F0/15 are listed in the port list, and a letter (P) appears next to each port, which is said to mean that the port is bound to that port channel. This code means that the ports have passed all configuration checks and can be included in the channel.Configuring Dynamic Ethernet ChannelsCisco switches support two different protocols, both of which allow switches to negotiate between themselves to determine whether a particular link can be part of an Ethernet channel. Essentially, the configuration enables the protocol for a particular channel group number. At that point, the switch can use the protocol in order to send and receive messages to and from each other and neighboring switches, and to check that their configurations have passed all checks. If a physical link passes the checks, it is added to the Ethernet channel; if not, it remains out of service and not used until the configuration inconsistency is resolved.So far, this section of the book focuses on how to make the Ethernet channel work properly, and later, in the "Troubleshooting the Ethernet Channel" section, several settings that can cause it to fail are discussed.Cisco switches support Cisco's proprietary Port Aggregation Protocol (PAgP) and the IEEE standard Link Aggregation Control Protocol (LACP) in accordance with IEEE standard 802.3ad. Despite the differences between these two, they both accomplish the same task in the depth of this discussion: negotiating to ensure that only configuration-checked links are included in the Ethernet channel.To configure either of these protocols, use the channel-group configuration command on each switch, and use a command that either says "use this protocol and beginnegotiations" or use this protocol and beginnegotiations" or "use this protocol and wait for the other switch to begin negotiations". As shown in Figure 2-7, the desirable and auto keywords enable PAgP, while the active and passive keywords enable LACP. with these options, at least one party must begin negotiations. In other words, for PAgP,one of the two parties to