In this article, we will discuss in detail the term Port-Channel, Ether-Channel or Link Aggregation. We will here also discuss the different modes of Ether-Channel or Channel Group.
A port-channel bundles physical links into a channel group to create a single logical link that provides the aggregate bandwidth of up to eight physical links. If a member port within a port channel fails, the traffic previously carried over the failed link switches to the remaining member ports within the port channel. A Port Channel can bundle up to eight ports into a static port channel without using any aggregation protocol.
All the ports in a port channel must be compatible; they must use the same speed and duplex. If no aggregation protocol is used, then the physical links are all in the “on” channel mode.
EtherChannel is group of multiple physical interfaces. It is a Cisco trademarked term. It’s the technology same as used by other vendors as Link Aggregation. Ether-Channel is what Cisco called Ethernet link bond initially. We can create Etherchannel using PAgP, LACP, or On. PAgP being Cisco’s proprietary protocol and LACP being the open standard
Types Of Channel Mode
An individual interface of a port channel is configured with channel mode. If no aggregation mode is used then the interface will set to “on“.
Active: Enable LACP unconditionally. A port in active mode can form a port channel successfully
with another port that is in active or passive mode.
Passive: Enable LACP only if a LACP device is detected. A port in passive mode cannot form a port
channel with another port that is also in passive mode, because neither port will initiate
On: Enable Etherchannel only. All static port channels (that are not running LACP) remain in
this mode. When an LACP attempts to negotiate with an interface in the "on" state, it does
not receive any LACP packets and becomes an individual link with that interface; it does
not join the LACP channel group. The default port channel mode is on.
Auto: Enable PAgP only if a PAgP device is detected
Desirable: Enable PAgP unconditionally
In short, we can say that “Ether-Channel = Port-Channel = Link Aggregation“
Refer to the article to know how to configure Ether-channel or port-channel on Cisco switches and also Ether-Channel or Port-Channel configuration on Dell Switches.