> | Lab 4.4.7 Show interface & clear counters Estimated time: 30 min. Objectives: Use the show interface command to display statistics for the router's interfaces. Use the clear counters command to clear statistics for the router's interfaces. Background: In this lab you will use show interface and clear counters. The router keeps very detailed statistics about data traffic it has sent and received on its interfaces. This is very important in troubleshooting a network problem. The clear counters command resets the counters that are displayed when you issue the show interface command. By clearing the counters you get a clearer picture of the current status of the network. Tools / Preparation: Prior to starting the lab you will need to connect a PC workstation with HyperTerminal to a router using the routers console Interface with a roll-over cable. This lab should be done at the router console station. You may want to review Chapter 13 in the Cisco Networking Academy First-Year Companion Guide and review semester 2 online curriculum chapter 4 prior to starting this lab. Work individually or in teams. Be familiar with the following commands: show interface clear counters Resources Required: PC with monitor, keyboard, mouse, and power cords etc. Windows operating system (Win 95, 98, NT or 2000) installed on PC HyperTerminal program Access to multiple routers Websites Sites Resources: Routing basics General information on routers 2500 series routers 1600 series routers Terms and acronyms IP routing protocol IOS command summary Beginning IP for new users Notes: Step 1 - Log on to router. Explanation: Connect to the router and login. Enter the password cisco if prompted. Step 2 - Enter the show interface command (abbreviated: sh int). Task: Enter show interface at the command prompt. Explanation: The show interface command displays packet statistics which reflect router operation since the last time the counters were cleared. 1. Fill in the following information for all interfaces in use:
> Interface | Ethernet 0 | Ethernet 1 | Serial 0 | Serial 1
> Hardware address |  |  |  |
> Packet input |  |  |  |
> Packet output |  |  |  |
> Last clearing of counters |  |  |  |
> Step 3 - Enter the help command. Task: Enter the help command by typing (?) at the router prompt. Explanation: The router will respond with all available commands for User-Mode. 2. What is the significance of entering (?) at the command prompt? Step 4 - Enter Privileged EXEC mode. Task: Enter enable at the router prompt. The router will ask you for the enable password enter class. Explanation: Entering the enable command and entering the password class allows you privileged mode access to the router. 3. What prompt is the router showing? Step 5 - Get help with the clear command. Task: Enter clear ? at the router prompt. Explanation: The clear ? command will display sub commands for clear. 4. Is counters one of the sub commands that is listed? 5. What is the description of counters? Step 6 - Clear all interface counters. Task: Enter clear counters at the router prompt. The router will ask you to confirm with (Y) Explanation: The clear command will clear all interface statistics on the router. Step 7 - Confirm that the counters have been cleared. Task: Enter show interfaces at the routers command prompt. Explanation: The show interface command displays the statistics, which reflect router operation since the last time the counters were cleared. 6. Have the counters been set to zero (0)? Step 8 - Generate network traffic. Task: Ping all routers interfaces in the lab network. Do this several times. Explanation: By pinging the interfaces of all routers on the labs network you will generate network traffic. You can use the Up arrow or CTL-P to retrieve previous commands and change the IP address to the next destination. Step 9 - Show interface statistics on the router. Task: Enter show interface at the router prompt Explanation: The show interface command displays the statistics, which reflect router operation since the last time the counters were cleared. 7. Fill in the following information in the table for all interfaces:
> Interface | Ethernet 0 | Ethernet 1 | Serial 0 | Serial 1
> Hardware address |  |  |  |
> Packet input |  |  |  |
> Packet output |  |  |  |
> Last clearing of counters |  |  |  |
Step 10 - Show interface statistics terminology. Task: Enter show interface at the router prompt. Explanation: The router shows information about the configured interfaces. Review the terms used for various interfaces and statistics. These can be helpful in troubleshooting. 8. Find the following information for interface Ethernet 0 with show interface: a. What is MTU? b. What is Rely? c. What is Load? d. What is a Runt? e. What is a Giant? 9. Find the following information for interface serial 0 with show interface: a. What is the IP address and subnet mask? b. What data link layer encapsulation is being used? c. What does "Serial0 is up, line protocol is up" mean?