Mastering EIGRP for IPv6: The Commands You Need to Know

How do you set an interface to advertise via EIGRP for IPv6?

• A. ipv6 eigrp 1
• B. eigrp advertise 1
• C. router eigrp 1
• D. ipv6 router eigrp 1

Answer: (A)

To configure an interface to advertise via EIGRP for IPv6, you need to enable the EIGRP process on the router's interface. The correct command, which involves enabling EIGRP for IPv6 on an interface, is "ipv6 eigrp X", where "X" represents the Autonomous System (AS) number for EIGRP. This command directly associates the specified interface with the EIGRP process, allowing it to start sending and receiving EIGRP packets for IPv6. The command "ipv6 eigrp 1" indicates that the interface will participate in EIGRP for IPv6 using AS number 1. This is a critical step in establishing EIGRP adjacencies and advertising the appropriate routes. The other commands do not fulfill the requirement for enabling EIGRP on an interface correctly. For instance, "router eigrp 1" is used to enter EIGRP configuration mode for the entire router, but it does not specify any interface. "eigrp advertise 1" does not represent a valid command in Cisco IOS for configuration, and "ipv6 router eigrp 1" is the command to enable EIGRP routing for IPv6 on the router level but does

When you're on your journey to crush the Cisco Certified Network Associate (CCNA) exam, understanding how to properly configure networks can feel a bit daunting. A key player in this domain is EIGRP, or Enhanced Interior Gateway Routing Protocol. So, how do you set an interface to advertise via EIGRP for IPv6? Let’s break this down in a friendly, yet informative way.

First off, let’s clarify what EIGRP for IPv6 is all about. Think of EIGRP as your helpful guide when navigating a complex city—you want to find the quickest routes, avoid traffic, and know where to turn next. In networking, this translates to how routers communicate and share routing information smoothly and efficiently.

Now, when you're looking to set an interface to transmit EIGRP for IPv6, you'll need to use specific commands, and here’s the kicker: It's essential to use the right command to enable the EIGRP process specified for that interface. It’s all about association! The command you’ll want to use is "ipv6 eigrp 1." This tells the router to enable EIGRP for IPv6 on a particular interface, linking it directly to the defined EIGRP process.

But why do we say “1” here? That number represents the Autonomous System (AS) number for EIGRP, which plays a major role in how routes are recognized and processed. Just like you wouldn't use the same route to get to different destinations in the city, each AS number directs EIGRP to manage routes uniquely. So, that command we just mentioned—the one that might be seared in your brain soon enough—effectively allows the router to send and receive EIGRP packets for IPv6.

You may be wondering about the other options that pop up in a typical CCNA practice scenario. Well, understanding what not to use can be just as crucial as knowing the right command. For instance, "router eigrp 1" puts you in the configuration mode for the router—great for overall settings, but it doesn’t actually set any interface to advertise EIGRP. And "eigrp advertise 1"? Sorry, but that one’s simply not in the Cisco IOS command playbook! Lastly, "ipv6 router eigrp 1" is used to enable EIGRP routing for the entire router but isn’t the command needed at the interface level.

So, let’s recap, because the repetition really helps—when it comes to enabling EIGRP for IPv6 on an interface, the magic command is "ipv6 eigrp 1." It’s a critical step that solidifies EIGRP adjacencies and gets your routes advertised correctly. The next time you sit down to tackle those routers, remember: one little command can make a world of difference in how your network communicates.

As you prepare for your CCNA exam, consider practicing with real Cisco configurations. Set up a lab environment with tools like Cisco Packet Tracer or GNS3—these can make learning feel less like a chore and more like a fun project. You’ve got the drive, and with the right commands under your belt, you’re well on your way to becoming a networking whiz!