5.1.2.8 Lab – Viewing Network Device MAC Addresses Answers

Lab – Viewing Netjob-related Device MAC Addresses (Answers Version – Optional Lab)

Answers Note: Red font color or gray highlights show message that shows up in the instructor copy just. Optional tasks are designed to enhance knowledge and/or to administer extra practice.

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Topology

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What is the OUI portion of the MAC deal with for this device?________________________________________________________________________________5C-26-0AWhat is the serial number portion of the MAC address for this device?________________________________________________________________________________24-2A-60Using the example over, uncover the name of the vendor that manufactured this NIC.________________________________________________________________________________Dell Inc.From the command prompt on PC-A, issue the ipconfig /all command and also recognize the OUI percent of the MAC attend to for the NIC of PC-A.________________________________________________________________________________Answers will certainly differ based upon manufacturer.Identify the serial number portion of the MAC resolve for the NIC of PC-A.________________________________________________________________________________Answers will differ based upon manufacturer serial number code.Identify the name of the vendor that produced the NIC of PC-A.________________________________________________________________________________Answers will vary based on manufacturer OUI.Tip 2: Analyze the MAC attend to for the S1 F0/6 interconfront.

You can usage a selection of commands to display screen MAC addresses on the switch.

Console into S1 and use the display interfaces vlan 1 command also to discover the MAC resolve indevelopment. A sample is displayed below. Use output generated by your switch to answer the concerns.S1# display interfaces vlan 1Vlan1 is up, line protocol is up Hardware is EtherSVI, attend to is 001b.0c6d.8f40 (bia 001b.0c6d.8f40) Internet deal with is 192.168.1.1/24 MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec, reliability 255/255, txfill 1/255, rxload 1/255 Encapsulation ARPA, loopago not set Keepalive not sustained ARP type: ARPA, ARP Timeout 04:00:00 Last input never before, output 00:14:51, output hang never Last clearing of “present interface” counters never before Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 Queueing strategy: fifo Output queue: 0/40 (size/max) 5 minute input price 0 bits/sec, 0 packets/sec 5 minute output rate 0 bits/sec, 0 packets/sec 0 packets input, 0 bytes, 0 no buffer Received 0 broadcasts (0 IP multicasts) 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored 34 packets output, 11119 bytes, 0 underruns

0 output errors, 2 interface resets

0 unwell-known protocol drops

0 output buffer failures, 0 output buffers swapped out

What is the MAC deal with for VLAN 1 on S1?____________________________________________________________________________________Answers will certainly differ based upon the switch the student is using. Using the output from over, the answer would be 001b.0c6d.8f40.What is the MAC serial number for VLAN 1?____________________________________________________________________________________Answers will differ based upon the switch the student is making use of. Using the output from over, the answer would be 6d-8f-40.

What is the OUI for VLAN 1?____________________________________________________________________________________Answers will certainly vary based upon the switch the student is using. Using the output from over, the answer would certainly be 00-1b-0c.

Based on this OUI, what is the name of the vendor?____________________________________________________________________________________Cisco Systems

What does bia stand also for?____________________________________________________________________________________Burned in attend to.

Why does the output show the exact same MAC attend to twice?____________________________________________________________________________________The MAC resolve have the right to be adjusted through a software program command. The actual deal with (bia) will still be tright here. It is presented in the parenthesis.Another means to display the MAC deal with on the switch is to use the show arp command also. Use the show arp command also to display MAC attend to information. This command maps the Layer 2 deal with to its matching Layer 3 deal with. A sample is presented listed below. Use output created by your switch to answer the inquiries.S1# display arpProtocol Address Era (min) Hardware Addr Type InterfaceWeb 192.168.1.1 – 001b.0c6d.8f40 ARPA Vlan1Internet 192.168.1.3 0 5c26.0a24.2a60 ARPA Vlan1What Layer 2 addresses are displayed on S1?____________________________________________________________________________________S1 VLAN 1 and PC-A MAC addresses. If the student likewise records the MAC addresses, their answers will differ.What Layer 3 addresses are presented on S1?____________________________________________________________________________________S1 and PC-A IP addressesStep 3: View the MAC addresses on the switch.Issue the present mac address-table command also on S1. A sample is shown listed below. Use output produced by your switch to answer the questions.

Answers Note: The present mac address-table command also deserve to vary based upon the design switch you are using. For example, the syntax on some switches is display mac-address-table.

S1# show mac address-table

Mac Address Table

——————————————-

Vlan Mac Address Type Ports

—- ———– ——– —–

 All 0100.0ccc.cccc STATIC CPU

 All 0100.0ccc.cccd STATIC CPU

 All 0180.c200.0000 STATIC CPU

 All 0180.c200.0001 STATIC CPU

 All 0180.c200.0002 STATIC CPU

 All 0180.c200.0003 STATIC CPU

 All 0180.c200.0004 STATIC CPU

 All 0180.c200.0005 STATIC CPU

 All 0180.c200.0006 STATIC CPU

 All 0180.c200.0007 STATIC CPU

 All 0180.c200.0008 STATIC CPU

 All 0180.c200.0009 STATIC CPU

 All 0180.c200.000a STATIC CPU

 All 0180.c200.000b STATIC CPU

 All 0180.c200.000c STATIC CPU

 All 0180.c200.000d STATIC CPU

 All 0180.c200.000e STATIC CPU

 All 0180.c200.000f STATIC CPU

 All 0180.c200.0010 STATIC CPU

 All ffff.ffff.ffff STATIC CPU

1 5c26.0a24.2a60 DYNAMIC Fa0/6

Total Mac Addresses for this criterion: 21

Did the switch screen the MAC deal with of PC-A? If you answered yes, what port was it on?

____________________________________________________________________________________

Yes. Port need to be F0/6. Answers will vary for the MAC deal with. In the instance over, the MAC deal with would certainly be 5c26.0a24.2a60.

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Reflection

Can you have actually broadcasts at the Layer 2 level? If so, what would the MAC deal with be?_______________________________________________________________________________________You deserve to have broadcasts at Layer 2. ARP will certainly usage broadcasts to discover MAC address information. The broadcast attend to is FF.FF.FF.FF.FF.FF.Why would certainly you must recognize the MAC deal with of a device?_______________________________________________________________________________________There could be a variety of reasons. In a big netjob-related, it may be much easier to pinsuggest place and also identity of a maker by its MAC address instead of its IP attend to. The MAC OUI will certainly list the manufacturer, which might assist narrow down the search. Security measures deserve to be applied at Layer 2, so understanding of allowable MAC addresses is essential.

Device Config

Switch S1

S1# show run