1005 BGP communites user defined

[Music] in this video we'll practically verify the bgp community attribute now we will see how exactly we can tag a specific routes when they are getting advertised to another autonomous sister number so we'll see how to define that community tagging with some specific routes by using rot map statements and then we'll also practically verify how the upstream router assuming that this is my service product how the upstream router is going to match those tag how it is going to write the community list and then how it is going to use the local preference or weight attributes which can be used for path manipulations by matching the community values so this is my scenario lab i'm going to take the same four routers which i use for all my laps but i have router 1 is configured inside your autonomous system number 500 and the remaining three routers are configured in the as600 so i'm going to assume this is my autonomous system number and maybe this is your service folder autonomous number now i have created a small requirement or a small task what we are going to do is we are going to advertise four different routes from here if you see i got four different routes eleven dot zero dot network the loop backs of router one 11.0.0.0 1.0 2.0 and 3.0 so when i'm advising these routes to router 2 or router 4 advertising to autonomous system 500 we are going to advertise with the community information of 500 column 10. so assuming that this is the community tag which we want to apply and the service portal wants us to advertise our networks with the community tag information and similar way we are going to analyze the remaining two networks when we advertising to our autonomous system 600 sorry it's 600 we are rising to 600 with a community tag of 500.20 so our requirement is we need to advertise our networks maybe in two categories with a community value of financial intent and 500.20 now which means the router routers inside the autonomous system number 600 will receive the routes with a committee value of 500.10 and 500.20 now based on that now the service portal is going to do path manipulation and i have created one small requirement that okay the requirement is any routes whichever coming with a community tag of 500 column 10 so in my example it's going to match these two networks maybe in the production networks you may have more than two or maybe you may have the same routes coming from a different customer you may have one more customer connecting and advertising with the same company value and one more customer but here for verification we are just using just one one customer side that is router one and any routes coming with this tank should prefer to exit yr router two means all the routes going outside our add-on system number should prefer like this so for that we are going to apply the local reference value of 200 or 250 whatever the number and all the routes which are committing coming with a committee value of 500 20 should prefer another exit path that is router 4 should prefer router 4 and we are going to apply the logo preference value something higher let's say 250 only for the prefixes which are coming with a committee value of 500 colon 20 and all the prefixes coming with a 500 column 10 should should prefer the exit wire router 2 with a local reference value of 200 this is my requirement here a small task or the small lab which i configured so let's try to verify all these things so the first thing to implement this all these things we need to have some basic pre-configurations now to implement and verify this we need to do some basic initial configurations like we need to configure ospf inside the autonomous system number 600 to provide reachability because this is a same adorama system number and we have three routers we need to have full mesh neighbor relationship or we can also use router factor concept so i'm going to configure ibgp pairing inside the same autonomous system number using loopback interfaces and to provide the reachability to loopback we are using osp of area 0 inside the autonomous system number 600 so the first task will be we need to configure ospf inside as an igp inside your autonomous system 600 to provide the reachability and then the next step will be we need to configure ibgp and ebgp configurations now all the ebgp configurations will be using directly connected interfaces and the remaining all ibgp configurations the internal bgp configurations are done by using the loopback interfaces or you can also use connect interface also but here as per my requirement i'm using loopback interfaces here so this is something pre-configured in my in my routers here so to verify i'll go to router router 3 if i go to my router 3 router 3 is already pre-configured with ospf configurations if i give show run section ospf command router 3 is already advertising its own connected interfaces and the loopback interface and the lan interface and similarly the same thing on the router 2 also i already did this configuration so bgb is also configured i'll come to the bgp configurations later on i'll go to router 2 and i'll show you the ospf configurations advertising the van interface two dot network twenty dollar network and the loopback interface because based on this look back we are going to form the neighborship now similarly router four is also configured with ospf advertising all the connected interfaces and the loopback and the lan interface whatever facing inside the as number 600 and to verify i can go to router 3 if i use show ipo spf neighbor i should see two neighbors router 2 and router 4 and if i give show ip.ospf i should be able to receive all the routes coming from rafter 2 and router 4. so router 1 belongs to different autonomous system numbers so we are not going to configure any igp towards router 1. now the next thing what we are going to do is we are we just configured this first task already it is pre-configured here and the next thing we are going to configure ibgb peering using loopback interfaces and the ebgp peering using all the connected interfaces okay so that is also pre-configured here so i'll go to directly router one and i'll show you the configurations what i did because you you are very well aware of this configuration so i'm not going to configure them here it's already pre-configured before i started so the router one is pairing with router two and router four and this is the two neighbor commands router two and router four and i'm advertising all the four loopback interfaces of the router one as you can see in the diagram here 11.0.0.1.12.13.1 and also i'm advertising the three connected interfaces two van interfaces and one lan interface so router one is forming the neighborship with router two and router four as ebgp neighborship and if i go to router 2 and verify there are two configurations now router 2 is appearing with external bgb neighbor and there are two internal bgp enables so which means total there are three neighbors and if you try to see here these are the neighbor commands one is external bgp enable this is my external pgp enable and then internal bgp neighbor using loopback interfaces so remote as an update source and analyzing the lan and the van interfaces now if i go to router 3 router 3 is having only two internal bgp neighbors so route to the reform neighborhood with router 2 and router 4 neighbor commands and advertising the interfaces similarly router 4 is also pre-configured with bgp show run section bgp now router 4 is forming one ebgp neighbor with router 1 and two internal pgp neighbors and anodizing the lan and the van interfaces so ospf and bgp is pre-configured here and you know the basic configurations you can find the same thing in my workbook here so the ospf and bgp is pre-configured and verifications to verify i can go to router 2 now router 2 must have how many neighbors two internal bgb enables and one external bgp neighbor so these are the two internal bgp enables and one is external bgp enable similarly i can verify the router four as well show ip bgp summary one ebgp neighbor and two internal bgp neighbors so all the all the routes are coming so if i give show ippgp i can see the eleven dot prefixes are also coming here and the twenty dollar network thirty dollar network forty dollar network coming from router 2 3 4. so i'm able to receive all the prefixes so next thing so coming to our actual requirement so what is our requirement here now we need to configure router 1 so we are going to configure router 1 and what is the task here configure router 1 to tag the 11.0.0.0 and 1.0 networks the low back zero and the loop back one interfaces with a committee value of 500 colon 10 and we are going to tag 11.0.2.0 and 3.0 with a community value of 500 colon 20 when it is advertising to autonomous system 600 so here my requirement is i want to ensure that when my router router one is advertising these two prefixes the first two should get advertised with a value of 500.10 that is the community value which we are going to apply and the remaining two low backs should get advertised with the 500 colon 20. these are the two company values when they are getting anodized on both the sides not only one side it has to be applied on both the sides so how to how to do that now it's very simple just like we did route filtering we need to match the first category of the networks in one acl so i'm going to match 11.0 and 11.1 in acl 11 and i'm going to use 22 acl for matching the remaining two networks and then we need to create a route map and we have to say match ip address 11 which means i'm going to match these two networks and we have to give a command called set community now when i am giving set community we are going to apply the community value now when i say set committee you'll find multiple values like you can define in an older format or you can define in a new format and these four values whatever you see these are well known communities which we have already discussed in a separate section in detail okay so even you can add to the existing community value by using an command called edit you now as of now i'm using this format and the format is 500 colon 10 where 500 is my autonomous system number and 10 is a number which i am attaching to those routes now similarly in the same route map we need to match the second acl which is going to match the second category of the networks and we have to give this command called 500.20

Channel: Sikandar Shaik

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Keywords: ccna, noa, ccna videos, ccnp, noa videos, cisco, ccie, subnetting, ccna security, bgp, ospf, firewall, ccna subnetting, ipv6, bgp videos, stp, ccna vdieos, ccna free video, ccie certification, ios, iou, virtual, eigrp, cisco virtual lab, iosv, asav, gns3, routing, noa vdieos, noa solutions, zone based firewall, zone pair, zbf, flsm, cisco firewall, cisco security, cisco certifications, wan, ip addressing, netmetric, vlsm, eigrp configuration, vlan, ccna, noa, ccna videos, ccnp, noa videos, cisco

Id: aEFm-ci-cF0

Length: 11min 39sec (699 seconds)

Published: Thu Jul 30 2020