2.3.11 Packet Tracer - Determine the DR and BDR

determine the designated router and backup designated router dr and bdr addressing table three routers okay three routers connected on a multi-access network okay each router is configured with a physical interface and loopback interface examine dr designated router and bdr backup designated router changing roles wait until the amber link lights turn green when you first open the file in pocket eraser you may notice that the link lights for the switch are amber these link lights will stay amber for 50 seconds while the stp protocol on the switch makes sure that one of the routers is not another switch okay wait for the green triangles the green indicators verify the current ospf network states use the appropriate command on each router to examine the current designated router and backup designated router if our router shows full dr other it means that the router is not designated router or backup designated router on array show ip or spf network okay go to our a command line interface enter enable show ip ospf network enter now you will see two night balls two lines okay rb and rc they are the ospf night wars of ra and look at the knight for id is 182 168 301 33 okay 31 3 is rc okay and also you can identify this router using the address 182.168.1.3 this physical address when i 182.168.13 or using the network id that in this case is the lubac interface is the network id okay and this is rc this is rc and rc is the designated router okay designated router the next line shows 31 22 this debug interface 3d 122 for rb okay and rb is the backup designated router backup designated router rb okay the same command on rb command line interface enter rename show ip ospf network enter you will see two night wars through the 111 11 is ra and ra is the designated router other okay so designated router order is not the designated router and is not the backup designated router okay it's other and 3133 rc 3133 is the designated router finally go to rc the command line interface of rc and you will see the output enter enabled show ipo spf network enter you you will see two night balls for rc the nice the nighthorse for rc are rb and ra and 31 11 is ra and ra is the designated router other and 3122 and 312 is the backup designated router okay which router is the designated router the designated router is rc which rather is the backup designated router the backup designated router is rb what is the ospf state of router ra okay you will see this on rc okay and 311 is the neighbor id and this is array and the state is designated rather other with on array you can see also on ra you can verify this okay you will see uh this theordy 1303 is rc and 0d122 is rb but to [Music] to view my own state you can use show ap ospf interface enter okay show ip ospf interface in my gigabit zero zero interface my gigabit zero zero here gigabit zero zero the state is designate that router other this is another way to verify tournament ipo spf at the essentia debugging you can monitor the dr nvidia relation process without the bach command on array and rb enter the following command okay on privilege excel mode the buff ipo spf adjacency okay go to our a enter the bar ap or spf ada okay enter okay ospf adjacency events debugging is on also on rb access rb the bach ib ospf abj enter okay it's on disable you can be ethernet 0 interface on rc shutdown command okay and disable this interface you gonna be zero zero on rc remember rc is the designated router and i will shut down gigabit zero zero okay configure terminal interface you go with zero zero shutdown and okay very good and now you can see the red indicator the interface is shut down wait about 30 seconds for the that timers to expire on ra and rb okay and wait 30 seconds and according to the debug output which rather was elected designated router in which router was elected backup designated router okay remember rc was the designated router but when the interface is shut down rc is not part of the network rc is not part of the ospf network so verify after 30 seconds okay go to rb and look at the debug at the end of the debug you can see the backup designated router is 311. now the backup designated router is 31.11 is ra remember previously ra was the designated router order and now is the backup designated router and the designated router is 18168 3122 and 312 is the router rb now rb is the designated router remember previously rb was the backup designated router and now is the designated router when rc is not present okay rb is now the designated router according to the debug output which rather was selected designated router and which router was selected backup designated router designated router rb and backup designated router ra restore javits using interface of rc okay we enable the link between rc and the switch okay go to rc access interface gigabit zero zero and no shutdown okay and you will see the green indicator okay wait a moment to this amber indicator turns green okay wait for the new designated router backup designated router elections to occur okay but wait a moment for the green indicator here okay wait about 30 seconds okay now you have the green indicators okay did designated router and backup designated router roles change explain okay and verify go for example to rc enter and to go privileged excellent mode and use show ip ospf network enter okay and you have two neighbors okay and rc has two neighbors rb and ra okay and 311 311 is ra and is the backup designated router and 3d 122 312 is the designated router okay no changes okay and verify the state of rc you can use and show ap or spf interface and on gigabit zero zero on rc on rc gigabit zero zero you can verify here the the state is designated rather other okay is other designated router and backup designated roles change explain no changes because ospf does not update the designated router and backup designated router when the existing ones are active okay if the designated router is available in this case rb the ospf process will not change the designated router okay will not elect a new designated router okay the same way with the backup designated router if backup designated router is available the ospf process will not elect a new device okay and okay and verify on rc already down okay disabled gigabit zero zero interface on rb okay remember now rb is the designated router and ra is the backup designated router and now down gigabit zero zero interface on rb this interface on rv shutdown go to rv enter configure terminal interface gigabit zero zero shutdown enter okay wait about 30 seconds and wait wait a moment now you can see the red indicator that indicates that interface gigabit zeros here on rv is shut down according to the debug output on our a which router was selected designated router in which router was selected backup designated router okay go to our a this router ra and at the end you can see this the backup designated router is 180 168 3133 this is rc backup designated router bdr and the designated router is 311 and 311 is ra and now ra is the designated router and rc the backup designated router restore jugabe zero zero interface on rb okay go to rb interface you go with zero zero no shutdown no space shutdown enter okay wait for the new designated router and backup designated router elections to occur the designated router and backup designated router roles change explain okay and wait for the green indicator here okay now you have the green indicator wait about 30 seconds and answer this question and go to rb enter and to go privilege exec mode and show ip ospf ospf natural bend and now you have two lines for the two knight words the knight force for rb rra and rc and 511 311 is ra is the designated router okay is still the designated router and here d3 is the backup designated router and 31 through d3 is rc is the backup designated router okay very nice and no changes no changes okay the dr and media roles change explain okay no no changes roles did not change because the current designated router and backup designated router are still active a router that comes online with a higher router id will not assume the backup designated router role until the backup designated router fails show ipo spf interface on rc go to rc enter show ip ospf interface enter what is the status of router rc now okay on gigabit 0 0 you can see the status of rc is a state backup designated router okay and is still the backup designated router no changes turn off the bugging okay enter a command on the back all on our a and rb okay our a enter enable on the back all enter okay and rb go to rv on the bar or enter very good turn it off very good and modify ospf priority and force elections configure spf priorities on each router to change the designated router and backup designated rather use the ipo spf priority command to configure the gigabit zero zero port of each router with the following ospf interface priorities for ra priority 200 for rb priority 100 for rc priority one this is the default priority this is the example for our a enter interface you can be zero zero and set the priority i ipo spf priority 200 for ra 200 okay and set the priority on router rb mrc okay start with ra okay configure configure terminal okay and enter this interface that is connected to the switch gigabit zero zero interfacing with zero zero and priority 200 ip ospf ospf prior really 200 and 200 enter now rb 100 go to rb click here configure terminal interface gigabit series here ipo spf priority 100 okay enter very good and on rc one the default okay go to rc enter configure terminal interface gigabit zero zero ib ospf spf priority one enter okay force an election by resetting the ospf process starting with router ra issued a clear ipo spf process on each router okay go to array okay to apply changes okay and to work privilege example okay and to apply changes and force a new election use this command clear ip ospf process clear ipo spf process enter reset all yes and now go to rb enter and to go privilege excel mode and clear ipos ospf process enter yes enter very good and go to rc enter and okay uh cli our ip ospf okay sorry enter enter a clear ip ospf process enter and yes okay very good and now wait a moment and finally verify designated router and backup designated rather elections were successful wait long enough for ospf to convert for the designated router and backup designated router election to occur this should take a few minutes okay and according to the output the show ipo spf network command under routers which router is now designated router in which router is now backup designated router okay remember ra has a priority 200 and ra is the highest priority so this should be the designated router okay our a should be the designated road rb has a priority of 100 and should be the backup designated router okay rv the backup designated rather and rc should be the designated router other okay rc the other okay and wait a minute and and now verify go to rc enter and use this command show ip ospf networks show ap ospf network enter okay and now you will see uh 311 is the designated router with priority 200 okay 311 priority 200 designated rather okay as expected is the designated router okay 3122 3122 is the rb and is the backup designated router okay i suspect that rb is the backup designated router very nice and verify the state of rc you can use show ip ospf interface showing the uspf interface to verify my own state enter [Music] gigabit zero zero the state is designated rather other because my priority is only one a lower value than 100 and 200 okay very nice completion 100 percent thank you thank you very much you

Channel: Christian Augusto Romero Goyzueta

Views: 1,820

Keywords: ensa, enterprise networking, security, automation, ccna, version 7, ccna 7, ospfv2, ospf, dr, bdr, designated router, drother, backup designated router

Id: BjdaTFtYP0U

Length: 25min 14sec (1514 seconds)

Published: Thu Aug 13 2020