2.7.3 Packet Tracer - Multiarea OSPF Exploration - Physical Mode (Part 1)

um casual recording company crc place it in sao paulo brazil provides self-serve me recording studios around the city so that anyone can rent a time slot and record their songs by themselves crc began with a single area ospf network located in one building this idea was very popular and consequently the business has grown causing the company to expand into a branch office in a second building at the far end of the city they continue to use single area ospf you will evaluate the impact of the expanded network okay this is the corporate office hq and branch office using single area or spf business is booming the i.t department in crc decided to migrate to a multi-area ospf network crc expansions continues crc has continued to grow and will open a new branch office in montevideo uruguay you will configure the area border router for the new area and physically connect the branch office network to the corporate headquarters network through the internet evaluate single area ospf network operation crc has expanded to a second location in sao paulo and currently uses single area ospf routing explore spf in the corporate headquarters click the cd icon for sao paulo okay click here on sao paulo notice that there are two buildings connected by a fiber link okay two buildings connected by this orange cable this is the fiber cable okay hq and on the right the branch office okay and they are connected by a fiber cable click corporate hq and then click the rack icon that represents the sao paulo hq wiring cluster a click on the wiring cluster click b1 ro4 and then select the command line interface tab okay two switches four routers another router down here and a pc okay click here on v1 r4 command line interface the terminal should show that gigabit zero zero zero and gigabit zero c1 are up and that four adjacencies have been established if not wait for the ospf loading process to complete okay you are on v1 r4 this the logical topology this this router and you should have four adjacencies the adjacency with b1 r5 another adjacency with other routers like b1 r3 r2 and r1 4 adjacencies just like this okay the [Music] gigabit zero zero zero up gigabit zero zero one up at the ascension with four routers okay very good now you can see b1 r1 b1 r2 r3 and r5 r5 is the router that uses the fiber optic to connect the the branch office in the another building okay this is b1 r5 the router that connects the branch office in in the another building soyber root command more press space okay and now you can see the the complete routing table and that is the size of the routing table and the roots learned via ospf from the routers in the sao paulo branch office okay this [Music] these are ospf networks ospf routes and two directly connected networks okay and 10-100 theory is this network on branch office 10104 10104 and branch office 10108 attention 08 branch office 12 16 20 12 16 20 and 10 20 0 1 10 20 0 0 this look back 10 20 1 1 10 22 1 10 23 1 10 20 1 0 10 20 2 0 10 20 3 0 okay 10 24 0 10 24 0 this network of the switch and pc 172 1710 this link the link between [Music] corporate hq and branch office the fiber link two directly connected networks two directly connected networks one eight one sixty eight zero eight a one eighty one sixty eight zero zero okay and zero eight and zero zero another ospf 18168 one zero down here one ninety one sixty a one zero one eight two one sixty eight two one and one eight one sixty eight three one 192.168.21 and 192.168.31 okay single area of spf very good execute on b1r4 execute show ipo spf command show ip o spf handle okay more space record the number of times the spf algorithm has been executed spf algorithm executed two times okay shortest path fields algorithm how many areas are displayed on router b1r4 okay only area 0 the backbone area areas here only one keep the console window for v1r4 object click b1 r2 command line interface b1 r2 click here command line interface execute the same two commands kb1 r2 enter enable show iproot enter space very nice okay this routing table is not complete okay repeat the show ip root space okay i recommend reload the router with save changes before to reload the router it could be running obviously to start up on the redirect reload okay and wait a moment for the network comprehense okay the knife for adiacian c with two routers uh [Music] b1 r2 should have three three night holes [Music] only two night balls enabled show ib roots okay but this routing table is so much better and remember the the networks the routes for branch office this the [Music] the link between corporate hq and branch office this link two directly connected networks two directly connected networks and the networks on corporate hq okay the networks on corporate hq okay compare the output of v1 r2 to the output of b1 r4 notice that the v1r2 routing table with the exception of local and connected routes has learned the same routes via ospf as v1 r4 so both routing tables are the same and obviously the only difference are the directly connected networks this this is the only difference the connected networks okay also remember execute the same two commands and also b1 r2 show ap ospf spf algorithm executed four times in this case and only one area the backbone area only one single area number zero okay record the number of times that the spf algorithm has been executed this four times explore ospf in the branch office keep the console windows open for b1r2 and b1r4 and the blue toolbar at the top back level okay but level this again click run branch office click the building on the right branch office click the wiring closet b2 r3 okay remember on branch office one two three four five five routers one switch and one pc one two three four five routers one switch and one pc okay b2 r3 b2 r3 click here okay enter the terminal should show that gigabit one zero into zero are up and the two adjacencies have been established okay b2 r3 1 0 up to 0 up two night war adia senses okay this is b2 r3 with two knight war adjacencies okay b two r three two nice words one a four is r4 and another knight is r2 okay it's very good shall i be roots enabled show ip roots okay okay and two directly two directly connected networks 4 and 12 4 and 12 2 directly connected networks okay networks on branch office voice ospf networks on branch office ospf networks on branch office the link between branch office and corporate hq the link between branch office and corporate hq and the one two three four five five routes to corporate hq with ospf one two three four five routes to corporate hq with ospf compare the output of b2 r3 to the output of b1 r4 or v1 r2 notice that other than a few connected or local routes the same networks are displayed okay b2 r3 v1r4 basically they are the same the same routing tables the only difference are the directly connected networks okay the only difference the directly connected networks show ipo spf show ap ospf record the number of times that the spf algorithm has been executed spf algorithm executed six times how many areas are displayed on b2 r3 b2 r3 one area see number zero only one click b2 r1 b2 r1 command line interface commander interface tab the output should be similar to the output of v2 r3 kb2 r1 okay enabled show ap root space okay the same routing table the only difference are the [Music] directly the directly connected networks basically the routing table is the same show ap ospf space only one area spf algorithm executed six times on b2r1 physical tab b2r1 click here physical tab zoom in and power the device off to simulate a power outage networks 10108 and 101016 will no longer be advertised okay if you will power off b2r1 is this b2 r1 and 10 08 and 10 10 0 16 will no longer be advertised okay b2 r1 power off click here on the power bottom joiby root and show ipo spf commands on one router in the branch office and one router in the head office i will use b2 r3 b2 r3 this router show ap root and 10 10 08 and 10 10 0 16 are not displayed and the another side i will use v1 r4 the under b1 r4 should i be showing root and 10 10 08 and 10 10 0 16 are not displayed are the two networks missing from both of the routing tables and have the spf algorithm execution increased are the two networks missing from both of the routing tables yes the answer is yes have the spf algorithm executions increased okay go to b2 r3 on b2 r3 show ip or spf spf algorithm executed seven times okay before was only six times so just increase it and go to b1 r4 b1r4 show ipo spf spf algorithm executed seven times before was two times okay so the exchange so the execution times are increasing so the answer is also yes every router in both buildings has been forced to do extra spf algorithm executions because all of the routers are in the same area every change to the topology will cause ospf to execute the spf algorithm on each router this is not a problem for small networks but for large networks excessive spf calculations can impact the network performance the solution is to divide the spf topology into multiple areas changes in the topology in one area will not cause spf recalculations in other areas you have completed part one to continue to part two close this packet razor okay thank you very much you

Channel: Christian Augusto Romero Goyzueta

Views: 899

Keywords: ensa, enterprise networking, security, automation, ccna, version 7, ccna 7, physical mode, packet tracer, ospf, ospfv2, neighbor, single area, multi area

Id: bO0iCiIjT4s

Length: 27min 14sec (1634 seconds)

Published: Fri Oct 22 2021