Exam 200-301 topic 1 question 190 discussion

on Mode that forces the LAN port to channel unconditionally. In the on mode, a usable EtherChannel exists only when a LAN port group in the on mode is connected to another LAN port group in the on mode. Because ports configured in the on mode do not negotiate, there is no negotiation traffic between the ports. You cannot configure the on mode with an EtherChannel protocol. If one end uses the on mode, the other end must also. auto PAgP mode that places a LAN port into a passive negotiating state, in which the port responds to PAgP packets it receives but does not initiate PAgP negotiation. (Default) desirable PAgP mode that places a LAN port into an active negotiating state, in which the port initiates negotiations with other LAN ports by sending PAgP packets. passive LACP mode that places a port into a passive negotiating state, in which the port responds to LACP packets it receives but does not initiate LACP negotiation. (Default) active LACP mode that places a port into an active negotiating state, in which the port initiates negotiations with other ports by sending LACP packets.

What helped me on this one was to think about what the other device would have to be configured to. For active, auto, and desirable, the other device would have to negotiate. However, with the "on" mode. There's no negotiation.

B is correct

Correct answer

https://www.cisco.com/en/US/docs/switches/lan/catalyst3850/software/release/3.2_0_se/multibook/configuration_guide/b_consolidated_config_guide_3850_chapter_0111110.pdf EtherChannel Modes You can configure an EtherChannel in one of these modes: Port Aggregation Protocol (PAgP), Link Aggregation Control Protocol (LACP), or On. Configure both ends of the EtherChannel in the same mode: • When you configure one end of an EtherChannel in either PAgP or LACP mode, the system negotiates with the other end of the channel to determine which ports should become active. If the remote port cannot negotiate an EtherChannel, the local port is put into an independent state and continues to carry data traffic as would any other single link. The port configuration does not change, but the port does not participate in the EtherChannel. • When you configure an EtherChannel in the on mode, no negotiations take place. The switch forces all compatible ports to become active in the EtherChannel. The other end of the channel (on the other switch) must also be configured in the on mode; otherwise, packet loss can occur.

Ref: Cisco IOS Software Configuration Guide, Release 12.2(33)SXH and Later Releases “CHAPTER 15 Configuring EtherChannels ... EtherChannel Configuration Overview .. Table 15-1 EtherChannel Modes On Mode that forces the LAN port to channel unconditionally. In the on mode, a usable EtherChannel exists only when a LAN port group in the on mode is connected to another LAN port group in the on mode. Because ports configured in the on mode do not negotiate, there is no negotiation traffic between the ports. You cannot configure the on mode with an EtherChannel protocol. If one end uses the on mode, the other end must also. ...” A. active Wrong answer. B. on Correct answer. C. auto Wrong answer. D. desirable Wrong answer.

B is correct!

B is correct

NO negotiation mode= ON NO = ON

Ref: https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/12-2/3-1-1SG/configuration/guide/config/channel.html

PAgP Cisco Proprietary protocol LACP Open Standard used by most of Vendors ON Forced to form Etherchannel without using negotiation protocol