SNMP Lab                

CT320: Network and Systems Administration                 

Description                

For this lab, we will execute SNMP commands with several different options. You will create a document with answers to the questions that follow. Number eqch question part.question, e.g., 5.3 for Part 5, Question 3. Show it to the TA when you’re done.                 

Environment                

On the Computer Science Department LAN, the only systems that responded to SNMP queries were HP printers and a Xerox copier. Here are the machines that we will use:                 

IP address	Name	What
129.82.44.62	tuba.cs.colostate.edu	printer in CSB 120
129.82.44.73	bassoon.cs.colostate.edu	printer on CSB 3rd floor
129.82.44.113	copier-1.cs.colostate.edu	Xerox copier/printer/scanner/fax

They all speak both version 1 and version 2c of the SNMP protocol.                 

Part 1 — SNMP Package Installation                

Ensure that the following packages are installed:

• snmp
• snmp-mibs-downloader

As super-user, execute the command download-mibs.                 

Ensure that the line “mibs :” in /etc/snmp/snmp.conf is commented out.                 

Part 2 — Using snmpget                

Use snmpget to retrieve some information about tuba:                 

    snmpget -v2c -c public tuba sysDescr.0
    snmpget -v2c -c public tuba sysUpTimeInstance

That’s correct: sysDescr.0 ends with .0, but sysUpTimeInstance doesn’t.                 

If you don’t have /etc/resolv.conf set up correctly, you may have to use tuba.cs.colostate.edu rather than just tuba.                 

Execute the second command several times; note that the time increases.                 

1. What does -v2c mean?
2. What does -c public mean?
3. What is the system description?
4. How long has tuba been up?

Part 3 — Using snmpwalk                

The snmpwalk command retrieves a bunch of information:                 

    snmpwalk -v2c -c public copier-1

It’s quite a lot—send it to a file, and view the file in an editor.                 

1. What is the system description?
2. Who is the system contact?
3. How many network interfaces are there?
   (Look at the lines starting with IF-MIB:: for network interface information.)
4. What are the interface types?
5. What is the MTU of each interface?
6. What is the physical address (alias MAC address) of the Ethernet interface?

Part 4 — Using snmpset                

Use snmpget to retrieve just the contact information for copier-1:                 

    snmpget -v2c -c public copier-1 sysContact.0

Now, use snmpset to change that contact information:                 

    snmpset -v2c -c public copier-1 sysContact.0 string "The Dread Pirate Roberts"

1. How did that work out?
2. Why?

Part 5 — Printer MIB                

We will now focus on one particular MIB, the Printer MIB.                 

Execute this command, which will display all the information defined in the Printer MIB, which is in /var/lib/mibs/ietf/Printer-MIB.                 

    snmpwalk -mPrinter-MIB -v1 -c public bassoon printmib

Send it to a file; view it in an editor.                 

1. Why did we specify -mPrinter-MIB?
2. Find the capacity of the paper trays, by looking in the output for prtInputMaxCapacity. There are two values, one for each paper tray. What are the values?
3. Find prtInputCapacityUnit in the output, which is the units used for prtInputMaxCapacity. That is, it says whether prtInputMaxCapacity is in sheets of paper, inches of paper, meters of paper, etc. Which one is it?
4. See prtInputCurrentLevel, which is how much paper is actually in the tray right now. What are the values?
5. Read the prtInputCurrentLevel entry in the MIB. What do the values from the previous question really mean?

Part 6 — Color Printers                

1. For each printer (tuba, bassoon, copier-1), fetch the values for prtMarkerColorantValue using snmpwalk. Which printers can print what colors?

Part 7 — Credit                

Show your work to the TA for credit.