- If you’re using GNS3 than load the Stub Area Networking GNS3 topology than start Router 1.
- Establish a console session with Router 1.
- Statically set the speed of interface FastEthernet0/0 to 100.
- Statically set the duplex of interface FastEthernet0/0 to Full.
- Configure interface FastEthernet0/0 with an MTU of 1520 bytes.
- Configure the bandwidth on interface FastEthernet0/0 to 10Mbps.
- Configure a delay of 10ms on interface FastEthernet0/0.
- Statically set the MAC address on interface FastEthernet0/0 to ca02.0adc.0ef9.
- Disable Keepalives on Interface FastEthernet0/0.
- Disable the Cisco Discovery protocol on interface FastEthernet0/0.
There are several key interface configurations that you’ll be required to know as a Cisco engineer. This lab lists some of the most common interface configuration attributes for a Cisco router.
The first objective of this lab is to statically set the speed of interface FastEthernet0/0 on Router 1 to 100Mbps. This is accomplished by using the speed command within interface configuration mode as shown below.
When statically setting the speed of an interface on a Cisco device, its best practice to statically set the duplex as well, this is accomplished by executing the duplex command within interface configuration mode.
When dealing with Ethernet WAN links or ipsec tunnel interfaces (outside of the ccna scope) it is common to change the Maximum Transmission Unit (MTU); which is the maximum payload a single packet can encapsulate. To complete Objective 3, you’ll need to execute the MTU # within interface configuration mode.
Objective 4. Configure the bandwidth on interface FastEthernet0/0 to 10Mbps. Do not get this confused with the actual speed of the link as the bandwidth command is used by routing protocols to calculate the dynamic metric. This interface configuration will be discussed further in detail in the upcoming sections.
Objective 5. Setting the Delay is very much like the bandwidth command; it does not statically set the delay but rather it is used in dynamic routing protocol metric calculation which again will be discussed in later sections. To accomplish objective 5, you’ll need to execute the delay command in interface configuration mode as shown below.
Note that Delay is measured in microseconds! 1000 microseconds = 1 millisecond
Objective 6. Requires us to manually set a MAC address on the FastEthernet0/0 interface. Manually configuring a MAC address is commonly required in a variety of scenarios such as mac address based authentication. To configure the MAC address for FastEthernet0/0, you’ll use the mac h.h.h command as shown below;
To verify this configuration without exiting interface configuration mode, execute the command do show interface FastEthernet0/0 as shown below.
Objective 7. Requires us to disable keepalives on interface FastEthernet0/0. First off what is a keepalive? Keepalives are a layer2 frame sent from the device to the device to determine if the Ethernet interface link is up. The device sends the frame out on the transmit ring and if the same frame is not received back then the device knows the the interface is down. To complete objective 7 you’ll need to use the keepalive command. Keepalives by default are sent every 10 seconds and to disable keepalives manually configure keepalives to the value of 0 as shown below.
The last objective of this lab is to disable CDP (Cisco Discovery Protocol) on interface FastEthernet0/0. CDP is a layer 2 protocol designed by Cisco to exchange device information with no underlying routed network. When you plug two Cisco devices directly into each other, they will both send and receive CDP frames by default on all ports (excluding frame relay which will be discussed in a later chapter). To disable CDP on a specific interface, execute the no cdp enable command in interface configuration mode as shown below.
To verify all configuration changes you’ve made in this lab you can use the same command you learned in the previous lab do show run interface FastEthernet 0/0 as shown below.