TechKnowSurge
Cisco CCNA 2.4 Cisco CCNA 2.2
TechKnowSurge Catalog Videos DEMO: EtherChannels on Routed Ports
VideoNetworkFree

DEMO: EtherChannels on Routed Ports

EtherChannel configuration between a Layer 3 switch and a router increases available bandwidth by bundling multiple physical links into a single logical routed port channel.

⚑ Complete this video to capture a CTF flag worth 1 point.

About this video

EtherChannel can be deployed between a Layer 3 switch and a router to increase available bandwidth beyond what a single physical link provides. Before beginning configuration, it is important to verify that duplex settings and interface speeds match on both ends, as mismatches will prevent the channel from forming correctly. The process on the switch starts with creating a port channel interface, issuing the no switchport command to convert it from a Layer 2 switchport to a routed port, and then assigning it an IP address since routed ports require one to operate at Layer 3. Each physical interface that will participate in the channel must also be converted to a routed port, have any existing IP address removed, and be bound to the channel group. In this configuration the channel group mode is set to on, which statically enables the EtherChannel without negotiation via LACP or PAgP, though either of those protocols could be used instead depending on the environment. Once the switch side is complete, the router must be configured using the same switchport-to-routed-port process, which requires that the router have a compatible switchport module installed. Without that module, the router-side commands cannot be demonstrated, but the logical configuration steps mirror those performed on the switch.

What you'll learn

What's covered

EtherChannel: Switch to Router

Aligned to

Cisco CCNA
2.4 Configure and verify Layer 2/Layer 3 EtherChannel (LACP)
2.2 Configure and verify interswitch connectivity

Key terms

EtherChannel
Cisco's implementation of link aggregation that bonds multiple physical links into a single logical channel to increase bandwidth and redundancy.
Layer 3
The Network layer of the OSI model, responsible for logical addressing and routing packets between networks.
Router
A network device that forwards data packets between networks based on IP addresses.
Routed Port
A switch port on a multilayer switch that has been configured to operate like a router interface at Layer 3 rather than as a switching port, allowing it to be assigned an IP address and participate in routing protocols. Routed ports are used where a Layer 3 boundary is needed directly on the switch without a separate router.
Port-Channel Interface
A logical interface that represents a bundled group of physical links configured as an EtherChannel.
channel-group
The Cisco IOS command used on individual switch interfaces to assign them to an EtherChannel group and specify the negotiation mode.

Topics

Etherchannel Layer 3 Switching Routed Ports Port Channel Link Aggregation Networking

Transcript

There are times when we want greater bandwidth between our switches and our routers. We've already taken a look from switch to switch and what the EtherChannels look like there, but let's see what it looks like if we are going to create more bandwidth in this scenario right here.

Planning the EtherChannel

What we're going to want to do is we're going to want to increase the amount of links we have between these two devices, this router and the switch right here, and we'll set up an EtherChannel in order to do that. One thing just to double-check before you start configuring things is making sure that your duplex and your speed are matching, and that things are not off from that perspective.

Creating a routed port on the switch

To create a routed port on a switch, it's really quite simple. So what we're going to do is — I'm on my layer 3 switch here — we'll get into the global configuration mode. From there we're going to get into the interface, and we're going to be configuring the port channel. We'll come up with a new port channel. Now, I'm going to just do port channel 3 here, so we'll get into port channel 3.

From there we're going to do a no switchport, so we're changing this from a switchport into a routed port. So we do a no switchport. Now that's associated with the port channel 3. And I'm going to do an IP address, so a routed port needs an IP address. So we'll assign just an IP address to this. So let's do 10.240.10.1, and we'll do just a /24, make it easy here, so it's a .0. So we assign the IP address to it.

Adding the interfaces to the channel group

Now we need to configure the interfaces to join this. So I'm going to end out of here, and then I actually do need to be in the global configuration mode, and then get into the interface. We're going to do 147 first, and at 147 we'll do a no switchport, so we're going to turn it into a routed port. We'll do a no IP address — we're going to just do this just to make sure that there's no IP address that's assigned to this. And then we'll assign it to the channel group, and we'll do three. And the mode — this is where we'll just choose on, we'll just turn it on at this point in time. There's, of course, we could do the LACP or PAgP, but in this case we're just going to do on. So I like to call that out specifically on these commands. So hit enter, and now that one's configured.

And then I'd run through the same set of commands for 48. So we'll do 48, we'll do the no switchport, and then no IP address, and then part of channel group three. And there we have the two configured. Now they're part of a routed channel group.

Configuring the router side

Once we configure our layer 3 switch, we would jump over to our router and then configure our router. Now, our router, or my router at least, has to have a switchport module installed on it to go through these very same commands. In which case, I don't have that module installed on it, so I'm not going to demo that part of it. But it would be the same process of setting up the switch ports on a router.

About TechKnowSurge

TechKnowSurge builds IT and cybersecurity professionals through hands-on, concept-first training built around real understanding — not memorization. Free interactive tools, structured programs, and 25+ years of real-world experience, all in one place.

Explore free tools and programs →