GNS3 - Basic Router Configuration (part 6)

What Will I Learn?

You will learn about Network Time Protocol (NTP)
You will learn about Cisco Discovery Protocol (CDP)
You will learn to configure NTP.
You will learn to configure CDP.

Requirements

Windows 7(32 bit) or more, Any Linux Distro - Debian/ Ubuntu are provided and supported
Cisco IOS device images.
GNS3 Software.

Difficulty

Difficulty is at an intermediate level.

Description

GNS3 or Graphical Network Simulator is a simulator used for virtual network designs, This software is an open source software and supports Cisco routers and switches by using an emulator known as dynamips. In this video tutorial we will learn what we mean by NTP and CDP. We will also learn to configure these protocols. We will learn to display this configuration as the Cisco Routers support both protocols.

You will learn about Network Time Protocol (NTP)

Network time protocol (NTP) is an application layer protocol which is used for clock synchronization between computers on a network. NTP is used to ensure that all devices on a network will agree on time. NTP uses client server architecture, from which one host is configured as NTP server. All other hosts are configured as NTP clients. In this video tutorial we will learn about the configuration of any device as our NTP server. We will learn to use different versions of the NTP and also learn to check the functionality of the NTP server. This video will help to configure and master our own device as the NTP server.

You will learn about Cisco Discovery Protocol (CDP)

CDP is also known as Cisco Discovery protocol and is a proprietary protocol from Cisco which is used to discover basic information. The basic information is about the attached routers as well as switches. With CDP, an administrator (user) can gather hardware as well as protocol information about neighbor devices which can also be helpful for the troubleshooting of the network or documenting the network.
To discover information of Cisco devices which sends the CDP messages out each of the interfaces. These specific messages contain information about the device that send the CDP message such as host name, Network and data link, link addresses etc. Below given sections will help to configure NTP and CDP.

You will learn to configure NTP.

Now we will learn to configure NTP on a Cisco device. Cisco routers as well as switches can be configured as both, NTP clients and NTP servers. To configure device as a NTP client we use the following command ntp server IP address where IP address is the address of the host we want to choose as the server. This can be shown with the help of figure 1 below. We can also define the version of the NTP server we want to choose for that we write a command ntp server ip address version 3 where ip address is the IP address of the host we want to choose as the server. This is also shown in figure 1.
We can also verify NTP functionality for that we use the command which is show ntp status. The command will help to know about the functionality of the NTP server that has been configured. To configure our own device as the NTP server we use the following command ntp master. The configuration of functionality and using our device as NTP server is shown below with the help of (figure 1)
PicsArt_04-17-07.46.22.png
(figure 1)

You will learn to configure CDP.

To discover information Cisco devices will send CDP messages out of each of the interface. These messages usually have information which included hostname, network, data link address, iOS version etc.
Now to display information for directly connected devices we shall use the following command show cdp neighbor. This command will help to get limited details of the routers connected locally to the device we are configuring. The information will be limited about the connected devices. This configuration is shown below in figure 2.
PicsArt_04-17-07.44.00.png
(figure 2)

If you want to get more information about the neighbors we use the following command in the command line show CDP neighbors detail . Detailed window will be displayed about the information related to the connected devices. The above shown configuration is given below with the help of a figure 3.
PicsArt_04-17-07.44.36.png
(figure 3)