Welcome back to this CCNA Prep video series where we have been looking at some of the scenario based objectives on the 200-120 exam.

In the previous video, we started our interface configuration exercise on one of the routers. In this video, we will complete the configuration on all other devices and also use various network connectivity verification tools like Ping, Traceroute and CDP.

New tutorial videos are posted every Monday, so keep checking back!

If you have any questions, or would like to suggest topics for future videos, please leave them in the comments section below.

Further reading:

Video transcript:

Welcome back to this CCNA Prep video series where we have been looking at some of the scenario based objectives on the 200-120 exam.

In the first part of this video, we started our interface configuration exercise on one of the routers. In this video, we will complete the configuration on all other devices and also use various network connectivity verification tools like Ping, Traceroute and CDP.

Let’s configure the other devices in our topology. We need to configure the serial interface on the ISP router.

On the VPCS, we will just assign it any IP address in the 192.168.1.0/24 subnet, for example, 192.168.1.100. You can use question mark or help command to get help.

My Putty settings don’t allow the help contents to show properly because of the colours so let’s change it. Cool.

We use the “ip” command to change IP settings. We can use “ip ?” to view the command usage. Our command will therefore be “ip 192.168.100/24 192.168.1.1”. The router is used as a default gateway in this case.

It’s always a good thing to test your configuration when you are done because you could have done something wrong.

Ping is one of the best verification tools available. It uses the ICMP protocol and sends a ICMP echo request and expects a ICMP echo reply

By default, Cisco IOS sends 5 ICMP requests; Windows OS sends 4.

Let’s ping the router from this VPCS. All we need to do is use the “ping” command and then the IP address we will like to ping.

Great! We have connectivity.

We can also ping from a Cisco router. For example, I will ping the ISP router from this router.

We can also use the extended ping option.

Another network connectivity verification tool is traceroute. Unlike ping which just tells you whether a network host is reachable or not, traceroute shows you the path taken to reach that host. On Cisco IOS, Traceroute works by sending out UDP datagrams with incrementing Time-to-Live (or TTL) values and waits for ICMP time-exceeded messages.

This command will make more sense in a larger network especially to troubleshoot issues of where a packet is being dropped but I will just show you how to use it here.

Finally, let’s view information from the Cisco Discovery protocol (CDP). CDP is enabled by default on all Cisco devices and supported interfaces.

The “show cdp neighbors” command is very valuable for information gathering. For example, you can determine what device is connected to an interface of your Cisco router.

CDP reveals a lot of information that may be seen as a risk from a security standpoint We can disable CDP globally using the “no cdp run” command. You can also disable CDP on an interface by using the “no cdp enable” command.

This brings us to the end of this video where we have completed our interface configuration. We used tools like Ping and Traceroute to verify network connectivity. We also used the Cisco Discovery Protocol to view information about connected devices.

I hope you have found this video insightful and I look forward to the next video in the series.