5.3.2.8 Packet Tracer - Examine the ARP Table

- sir welcome tour in this video we are going to see the packet race or activity examine the ARP table we will go through the objectives in part 1 we will examine an ARP request in part to examine a switch MAC address table in part 3 examine the ARP process in a remote communications here is the background this activity is optimized for reviewing PD use the devices are already configured we will gather PD information in simulation mode and answer a series of questions about the data we collect right this is what we are going to do in this packet tracer activity we will come to path to one first examine an ARP request so in that step one generate a RP requests by pinging 170 2.16 dot 31.3 from 170 2.16 or 31.2 right this is what we are going to do now click 170 2.16 dot 31.2 and to open the command prompt enter the ARP space - D command to clear the ARP table then enter simulation mode and enter the command pink 170 2.16 dot 31.3 - PD will be generated the ping command cannot complete the ICMP packet without knowing the MAC address of the destination so the computer since an ARP broadcast frame to find the MAC address of the destination right we will come to this now yes we have to go to 170 2.16 or 31.2 Monsieur it is right we are going to desktop command prompt oops this is terminal command prompt alright to here we are going to clear the ARP table so if we had to give a RP minus D then we are going to press ENTER right now we will go to a simulation mode okay you're now we are in simulation mode and we are going to ping to 170 2.16 dot 31.3 that means we are going to ping from this PC to this PC right you're going to give a pink yes 170 2.16 dot 31 door 3 yes now you are going to press ENTER yes here we can see here a 2 PDUs generated we will check these PDU so here we can see this is ICMP and - this is a RP so before ascending this ARP we will be sending this ARP for getting the mattress great now we will go to addy click a capture or forward once the ARP PDU moves the switch to 1 while the ICMP PDU disappears waiting for the ARP replay open the PDU and to record a destination MAC address is this address listed in that table above we will verify that now now we will click capture or forward here and we can see that ICMP PDU is disappeared and this ARP now went to a switch we are going to open this PDO ARP here we will verify the destination MAC address here we can see the given F F F F dot F F F F dot F F F F and this address is specified in this addressing table you know it is not places per specified obviously it is this address is a broadcast address next is click capture or forward to move the PDU to the next device how many copies of the PD you did so to one make right we will verify that we are going to click on capture or forward again here we can see three copies made here we can see one goes to router one goes to 31.3 and another goes to 31.4 so total we got three copies of the PDU now we will go to the next question what is the IP address of the device that accepted the PDU here we can see these two PDUs are not accepted by these devices and to here we can see 170 2.2 16 door 31.3 is accepted the p do next is opened the PDU and examine layer 2 what happened to the source and destination MAC addresses right we will verify that here is or PDU and here we are going to verify that yes here we can see the source became destination previously this was the source a truss ffff so it became a destination and that F F F F that means the source actress turned into MAC address of 172 dot 216 dot 31.3 here we can see that 2 0 0 0 0 date fire you see sido - 1 da 7 next T is click capture or forward until the PDU returns to 170 2.16 dot 31.2 how many copies of the PDO did the switch make during the ARP replay right we are going to click capture or forward so it goes back to su CH and again capture or forward here we can see it a replay with the only one PD you to this our device 172 dot sixty dot 31 or two from our assets now we will come to a step to examine the ARP table note that the ICMP packet array appears yes here we can see that this is ICMP and we do keep the cursor on that so that we can see yes it's ICMP correct now open the PDU and examine the MAC addresses do the MAC addresses of the source and destination aligned with their IP addresses yes we will across check that coming to this ICMP PDU yes here we can see that so the MAC addresses of the source and destination aligned with the IP addresses now we will come to be the switch back to real-time and ping completes click 170 2.16 or 3102 and they enter the arp - a command to what IP uh trust does the MAC address entry corresponds ok and we will verify that now we are going to real-time mode so that our ping completes yes and now we will come to the device 170 2.16 dot there T 1.2 and command prompt - here we will give a RP - a right and to here we can see corresponds to 172 dot 216 dot that even door 3 here the last question in general when does an NT device issue and ARP request so obviously and into device when it does not know the receivers Mac uh trust then he will send an ARP request no we will come to party to examine a switch MAC address table so in that step one generate additional traffic to populate the switch mica trust table so from 170 2.16 door 31.2 until the ping 170 2.16 dot 31.4 command then click tender tender 10.2 and to open the command prompt enter the ping 10 dot and or 10.3 command then how many replace were sent and to received okay we will verify this now first we will come to 170 2.16 dot 31.2 and we will pink to this a PC 170 2.16 dot 31.4 all right come on prompt here we are going to give a pink 170 2.16 door 31 whoops yes that even dot for central writes we are getting the replay now we are going to ping from this laptop to this laptop coming to this laptop command prompt and here we are going to pink tender tender 10.3 and we are getting the replay here we can see the packets are sent to for and received for now we will come to step to examine the MAC address table on the switches click switch one and then the CLI tab enter the show MAC address table command do the entries correspond to those in the table above so we will across check that now coming to switch 1 CL I yes here we are going to give the show command so we have to go to privileged exit more so MAC address table and to here we can see the details so we have to cross check with our trust table here is our dressing table and we are going to verify these are truss here we can see the etre starting with the 0 0 2 yes here we can see that yes and the 0 0 c8 v you see see here we can see that this is a device 170 2.16 dot 31.2 and so here we can see that zero zero zero yes here it is this is the interface of router one yes next is clicks it's zero then the CLI tab enter the show Mac at a stable command do the entries correspond to those in the table above we will cross-check that coming to suit 0 CL I and here enable and we are going to give a show make a trust table and here is the manga trusses you are going to verify with our addressing table yes your it is 0 0 1 here we can see obviously we can see here it is and the 0 0 6 0 to f8 4s here we can see that and this 0 0 6 0 4 7 0 6 5 7 to be years your it is now we will come to the last question in this step 2 why are 2 MAC addresses associated with the 1 port ok here you can see that here is a port of Fast Ethernet 0 / 2 and faster there are 0 / - yes so this is associated with the 1 port so coming the topology here we can see these laptops are connected to access points and this access point and this access point is connected to switch using one port so that's why it is showing that one for there now we will come to part 3 examine the ARP process in a remote communications step 1 generate traffic to produce a RP traffic click 170 2.16 dot 31.2 and to open the command prompt enter the pink tender tender tender to one command type a RP space - a what is the IP address of the new ARP table entry right we will verify this now we will come to 170 2.16 dot 31.2 and it's command prompt now we are going to ping - you can write we will type it pink 10.10 dot dot one you are going to present or yes we are getting the replay right now we will type ARP - a coming to that - here we are going to give a RP - a and two here we can see that to 172 door 216 note that even note 1 yes we will come to the next enter a RP minus d to clear the ARP table and the switch to simulation mode repeat the ping - 10 - 10 door 10.1 how many PDUs appear so obviously it will be 2 because we are grilling clearing the ARP right we will do that come on prom - here we are going to give a RP minus D and we will switch to simulation mode and we are going to pink again yes yes here we can see that one is ICMP and another one is ARP yes next is click capture or forward click the PDU that is now at SU to 1 what is the target destination IP destination arches of the arp request right we will check that capture or forward yes it goes to switch 1 we are going to open that and 2 here we can see the destination IP address 170 2.16 door 31.1 here we can see this our treasure is a destination at just 172 dot - 60 31.1 is the IP address of this interface on a router one that is Gigabit Ethernet 0/0 yes here we can see that yes now we will come to a G the destination ie Pietra C is not tender 10.10 dot one why yes just now we have seen that it shows the IP address of this router interface so that is nothing but the default gateway for this network 1 7 2 dot 16 or 31.1 so the gateway address of the router interface is stored in the ipv4 configuration of the host if the receiving host is not on the same network the source uses the arp process to determine a MAC address for the router interface serving as the Gateway now we will come to a step to examine the ARP table on router 1 so to real-time mode click our outer one and then the CLI tab enter privilege to exit mud and then the show MAC address table command how many MAC addresses are there in the table and two why right we will verify that now now we will move to the real-time and you know will come to router 1 CL I yes so here we are going to give the show command show Mac right yes here we cannot see any Mac uh trusts in this table so this command means something completely different than the switch command show MAC address table yes that's why no we will go to a see enter the show ARP command is there any entry for 172 Road 16 dot 31.2 alright we will verify that here we are going to give you show ARP and so we are going to check for or 172 door 16 door 31.2 yes here we can see the entry and to hurry so last question what happens to the first two pink in a situation where the rotor responds to the ARP request obviously it times out well in this packet race or activity we examined the ARP table so that's all in this a packet race or activity reference if you have any doubt please comment below also if you like my video give a thump and don't forget to subscribe the channel so that you will get latest uploading video info into your Gmail thank you

Channel: Tech Acad

Views: 45,853

Keywords: ARP

Id: pJxBfEdWi54

Length: 18min 23sec (1103 seconds)

Published: Mon Sep 11 2017