Edited Quiz: EIGRP for the CCNA | Cisco CCNA 200-301

[Music] hey everybody how you doing glad to have you here my name is keith barker and we just had a quiz on sunday at 11 a.m pacific time and what i did is i took that recording and then i edited it down so if you're watching the recording of this it's a lot quicker here's a quick breakdown of how it'll run i'll introduce a question and then i'll give you in the corner of the screen a countdown of five four three two one and boom and then the actual answer will appear and then any explanations i include the benefit of doing that is as you're watching this video when you see me doing that countdown five four three two one pause it and that'll give you as much time as you need to think about the answer what it is why it is and then you can click on resume and see the answer so without further ado enjoy this recording of the live quiz our focus is on eigrp today that's the enhanced interior gateway routing protocol from cisco here is question number one it's multiple select what goes in to the eigrp metric calculation by default i'm looking for two correct answers here all right bandwidth and delay are the two major components that go into the algorithm for this composite metric the eigrp generates fantastic here's question number two it is double points no pressure eigrp just learned two internal routes to the same network which one will it use the route with the lowest composite metric how is that possibly true let's talk about that for a moment so let's imagine this is a router one and router one's happy because it's running eigrp at dynamic routing protocol which is really a surely a distance vector routing protocol that keeps track of its immediately connected neighbors uh so r1 is here it just learned two routes about the same network let's say it learned about let's see r2 and r3 and let's say r4 there we go so let's imagine we have a connection here a connection here a connection here connection here and then we have network 4.4.4.4 32. that network has been advertised from r4 to r3 into r2 and then they advertised it to r1 and the eigrp routing process just learned about that network from two different sources two internal routes uh to the same network one going this way and one going this way with the grp the default administrative distance is 90 so it would be a 80 of 90 for both of those learned routes so the question is which one has the lowest composite metric and that's the one that would be used basically is once it's in the routing table the one that has the the least cost is going to be used let me give you an example of what that might look like this is a little different but i think you'll do great with it i'm just going to put eigrp on all these devices they've got a multi-layer switch which is routing we've got router 1 router 2 router 3 and router 4. none of them are running ea grp yet so we'll do a config t and we'll do a router eigrp one and we'll say network now if you're brand new to eigrp the network statements work very much like they do with well very similar to they do with ospf so if you don't know how network statements work with ospf yet uh no worries uh once you study that you can go back and revisit here so with eigrp the network statement simply says which interfaces are we going to include so i'm going to say network um 0 000 and there's no areas in eigrp so we don't say area zero so that basically says to this router and all the routers hey please enable eigrp on all interfaces that are running ipv4 and then we have some adjacency that just came up and it's done i did that command on all routers all devices so we went to router 3 for example and we said show iprout and then say i'm going to say eigrp and what that does it says please show me the ip routing table but just show me the output for eigrp learned routes only and that'll thin the output a little bit so look at this route right here so we have a route to 2222 that we've learned and the d over here on the left shows you how that route was in put into the routing table where it came from and the d says it's eigrp all right fantabulous eigrp learned route and this shows us that we have the administrative distance of 90 for both of them and we have the same composite metric aka cost or metric and eigrp it's a composite metric it's made up of those calculations from the previous question like the bandwidth and delay and the calculation based on those two factors and because they're equal cost the metric is the same the composite metric these are equal cost routes it's gonna use both of those routes but um what's happening also behind the scenes is that there's a third route that is possible and it's not showing up in the routing table because it didn't have as good of a cost as these two these two have the lowest cost if we do a this is the command you probably won't need for ccna but it's good to know just to see what's going on behind the scenes that show let's see ip eigrp topology and let's just take a look at that two two two route right there so this is showing you from like think of it like the database for ea grp here it says okay for the network 222 i've got two successors spoiler alert here's a giveaway for another question coming up a successor route is a winning route that means it got into the routing table not only did the router learn about that route but it put it in the routing table as a winner so if you see the word successor all by itself or or route just think that's a winning route and so it says for two two two two with the 32-bit mask i've got two successors and they are uh and also it says the feasible distance is 131 072. feasible distance is another fun word fun set of words and here's what it means feasible distance equals cost or metric or in the case of ea grp the composite metric so if it says 131 thousand 072 right here when we do a show ip route in fact let's just scroll up and do that real quick let me get my hide that for a moment thirty one thousand hundred thirty one thousand 72 remember that for a moment look at this look at that value right there for the metric 130 1072. so the feasible distance in eigrp is the actual metric or cost or a composite metric that it uses and this is just another way of looking at that same data so going back to this bad boy right here um let me get my pen out so we have two routes that won and that's because these two oh look at that look how big that pen is oh my gosh click click undo all right massive pen strokes there so it says we have two successors that means we have two winning routes so here's the administrative here's the uh the metric and these two routes have that metric right here and so the successor routes are this guy and this guy so that's why in the rounding table it shows two routes now look at this one right here this next one that has the next hop of 10.23.0.2 it has a metric of 131 328 so it's not as good as the others and so for the question that we just addressed if we're learning multiple eigrp routes for the same network and which one's going to be used it's the one that's going to have the lowest cost between the eigrp routes and if we have two equal cost routes they're gonna be used um so this is actually the uh the cost of the composite metric and i'll talk more about the feasibility condition and a subsequent question so that's a little bit more than you probably knew about eigrp if you're brand new to it i'd also encourage you to watch that video that i published a few months ago on eigrp and uh it'll help as well with a lot of these basics which eagrp network statement includes the 10.2.0 network with the 24-bit mask and multiple select so choose at least one or up to all of the correct answers the big reveal don't hate me [Laughter] all these are valid for eigrp let's talk about why for a moment with eigrp we'd go into router configurations by saying router space e-i-g-r-p space and then we'd have an as number so if we're using autonomous system number one all the routers would need to use as number one so they would be willing to neighbor up and participate as part of eagrp there's also an option called named eagrp which goes beyond the scope of what i want to talk about today but routerio grp that puts us into router configuration mode let me change my pen just a little bit and then what we do is specify a network statement now a network statement is a lot like telling the router hey listen match any interfaces you have based on this part of an ip address and if it matches include those interfaces inside of eigrp so let's go ahead and take a router we'll call this router 6 and it's got an interface we'll call it gig 0 0 and on that interface it has the address of 10.2.0.50 and that's a with a 24-bit mask all right so if you're new to subnetting new ip addressing come see me in subnet saturdays it's 11 videos long you'll be an expert at doing ip addressing and subnetting in no time just by following that playlist here on the youtube channel okay so on this interface if we wanted to which is what this question is how do we include 10 to zero so his host address is 50 on this network if we did a network statement of this network let's start with the easy ones here let's start with let's start with this one this green one is a wild card for eigrp it basically says any interface is running e running ipv4 include those just every single one in ospf we do zero zero zero zero and then a wild card mask of 255 25 25 285 um but we don't need to here with eagrp that's a wild card that says everything so that would cover 10.20 and any other ipv4 interfaces that were configured on r6 all right let's go to uh this right here network 10.000 if we just typed in network 100 it says oh that's a class a address and so i'm just going to pay attention to the first octet the 10 and any interfaces i have that start with 10 i'm going to include inside of eigrp and that also would be true if we said 10.9 dot or something crazy because it's a class it's a class a address it wouldn't even care by default about those last three octets if you say i don't care class a we just matched on the 10. so that would include 10 2. so that's why this color here is true this one here network 10200 with a wild card mask saying i don't care about the last octet because we included the wildcard mask it basically says i don't care what that last octet is any interfaces that begin with two zero including gig zero zero is going to be included in eigrp and that's why that one's true and then this over here is network ten zero zero zero with a wild card mask saying i don't care about the last three octets so the wild card masking piece works just like that does with ospf except there's some shortcuts right here like with network zero zero zero and network ten zero zero where we don't have to include a wild card mask at all and eigrp will interpret it based on the class of address it is or if it's all zeros saying all interfaces nice work everybody question four of nine here you go which routing protocol can do unequal cost load balancing [Music] all right eigrp can do unequal cost load balancing and i think we should see that in motion so check this out if we go to r3 and we do a we do a clear screen and we do a show ip route for eagrp it's got two equal cost routes for two to the network two two two two one's going through it looks like r4 based on the last octet and how i numbered them and another one going through uh router one and we look for that same network of uh this guy right here two two two two this says that we have two winners two successors where the cost or the feasible distance is 131 thousand that hasn't changed and here are the two winners and this third one here they see how this metric is slightly higher bummer um because the metric or the feasible distance is slightly higher it didn't make it into the routing table but here's something cool that eigrp does eigrp can also keep track of a route that didn't quite make it into the routing table but might be able to be used if the other routes go away and that's what's happening with this third route it's it's good enough to stay in the topology table but it's not good enough to make it into the routing table because the routing table only takes the winners unless unless we tell it to use a little leniency what we could say is hey dear mr ehrp if you have these backup routes waiting in the wings go ahead and use them if they're like maybe only half as bad as the primary out or a third is bad or a fourth is bad meaning the metric could be two times or three times or four times what the other metrics are so to do that let me show you how that's done this is just interesting uh i wouldn't worry about the full config for eigrp for ccna but it is fairly interesting so right now if we do a show ip route for it for eag or pre-learned routes it knows about just those two routes but it has that third one with a slightly worse metric and we can bring it into the routing table like this router eigrp same autonomous system number and then we can do a variance command and variant says how bad how bad can the next possible or feasible backup route how bad can that metric be i'm going to say two and that just means it can be twice as bad so if we scroll up a little bit before i press enter this metric right here 131 328 it's just slightly worse than the the successor routes so two is gonna be way and you know you have to go in increments of you know one digit so that'll bring this route which will now show up we should have a new route coming in the routing table with dot two as the next top so let's uh let's play that out and see if it works variance of two boom show ip route eogrp is what i want to do and and crossing his fingers look at that for two two two we now have three routes we've got two that have a pretty darn good composite metric and we have one that's slightly worse but it made it in because we use the variance command this is an example of unequal cost load balancing so this is what eigrp is doing also one more thing and then i'll go back to the next question and that is this we do the topology again there is something i'm a little nervous to even tell you about but there's something called a feasibility condition and i'll write it out here fees uh fees uh how do you spell feasibility fees uh feas is it i feasibility visa all right there may be a typo there we'll find out here in a moment feasibility condition and here's what the feasibility condition is it says uh for this route right here which is uh the one with the slightly worse metric it the reported distance like this is uh we're on r3 so when r3 is learning about you know the these routes from its neighbors this number here on the right is recalled the reported distance it's like the the value reported by like r1 or r4 who's reporting it in and think of it like the the base guts of how r3 is going to build its own calculations working to throughout the the short story is of the feasibility condition is that for this feasible successor which was what it was called before we made it in the routing table for a feasible successor means a route that could be used and could be put in the routing table the advertised or reported distance right here that it learned from the neighbor has to be less than the current feasible distance so the current metric is 131 000 the reported distance from the neighbor is 128 000 which is less and that's why this is showing up in the routing or that's why it's showing up as a feasible successor route and then with the variance command we kicked it over the edge and said hey bring it to the party so that's that's probably more i wouldn't worry about memorizing feasibility condition yet but when you get to ccnp level you'll be glad that you did and uh there are some terms coming up like feasible successor feasibility condition and successor that we've had a chance to discuss which will be important to you absolutely yes oh my gosh it is great to have everybody in the house love it all right let's continue on this is question five of nine what is a feasible successor and these are randomized so i even though i just talked about that a moment ago i wasn't sure what order it would come up in [Music] all right it is a it is a backup route so unless we're playing the variance game the feasible successor is the route that's not quite as good as the successor routes but it's feasible and that's because it meets the feasibility condition but it's feasible it could be a route if we change the variance or the two primary routes leave the leave the picture and then it can be automatically put into play so that's what a feasible successor is think of it like a backup route that eigrp is hanging on to in the event it needs to put it into the routing table all right great job everybody next we have question six of nine what is a successor route in the igrp oh my gosh we just talked about this what is a successor route all right great job is the winning route is the route that wins and so if we do a show ip ea grp topology it's going to show us how many successor routes we have and then we should see those same exact routes in the routing table in fact let's take a quick peek just to confirm okay so i've got three routes to two two two two so we do a show ipea grp topology i it should show three successor routes and that's because we did the variance command and we're taking in this little slightly less than perfect uh metric and bringing them in but if we did this and we went to router eigrp autonomous system one and said no variance that goes back to the default so variance of one effectively we can verify that let's show ip protocols and i think it's gonna be here yeah right there so this is the output of show ip protocols so there's the variance there's the network statement and if we do a show ip eigrp topology we should have four two two two two look at that now we have two successors that means two routes that made it into the routing table and this guy is showing up here is now what's called a feasible successor it's feasible he could be used if the other two better routes go away or or if we have variance that's greater than one which is currently the default all right all right all right all right here we go question seven of nine multiple select double points no pressure here it is r1 learn the route to four four four zero slash 24 via all these protocols which of the following are true i'm looking for two correct answers well if we learned about all those routes well i should say r1 so this is r1 and it learned about the network 4440 that exact route via internal bgp uh internal bgp has an ad of 200. i'll put uh not 2000 keith that's a lot i'll say i bgp which is bad so ad is like the lowers like golf lower is the better ospf has an ad help me out here let me chop it go ahead and tell uh put in the comments what is the ad for ospf let's go ahead and type that in if you would help me out fantastic it's 110 answers are pouring in okay let's keep up the move then for eigrp internal routes what is the ad the administrative distance for eigrp internal routes and those numbers are pouring in fantastic that has an ad administrative distance of 90 and rip may it rest in peace what is the administrative distance for rip and once again thank you for those fantastic answers all i mean spot on great great great great all right so if r1 learned about this route from ibgp and ospf and eagrp and rip it's gonna prefer eagrp learned routes because they have a low it's the same exact route 24 bits it's gonna choose the one learned via grp because the default ad is 90 which is great oh there we go so we would see that that's green and then if that route went away the next best route would be ospf because it has the the next best after eight after eagrp fantastic so it's red and green next question question eight of nine double points oh we're getting near the end here when will a rip route be used instead of an eagrp route i mean how could that happen we just had the discussion about a.d is there a correct answer here and if so what is it all right when it's a longer match is absolutely true and what i mean by that is something like this if i'll take router one we'll pick on him again if in router one's router table it has a route at eigrp learned route to 10.10.10.0 24. fantastic and then it has a rip learned route to 10.10.10. say 0-25 those are two different routes however if a packet is being forwarded to 10.10. let's say something less than 128. how about 50. there we go 1010 1050 matches both of these routes right i mean this one we'll call this route a and route b they both would work but this is a longer match so they're both in the routing table because they're different networks as far as the length is concerned and the rip route would be used because it's a longer match so once the routing table is established it's always the longest match and here's our final question which of the following is not an eigrp term i'm looking for one answer here fastest correct answer gets the most points for this question no pressure wow nice lsas link state advertisements that's an ospf thing for a link state routing protocol and grp has none of that all right fantastic work and here's the podium [Music] all right great job to everybody if i could get a little bit oh look this is great this is the most difficult question out of all nine questions i think we had uh which erp network each which eagrp network statement includes 10.200. that was the hardest one that is that bodes very very well for a lot of people now as a whole we did like 46 but this was the toughest question which is great stuff also if you take a moment and give me your feedback that'd be great i appreciate that and then what i'd like to do is i will edit all of this up and put on a re uh the edited version so it's nice and tight and if you want to go back and review it later you can and let me take a few minutes right now and answer any questions that you might have i want to focus on ccna if it's beyond that i'll just let you know we can address that a different way but if you have any questions about you know ccna or eigrp or whatever if it's ccna related just go ahead and do an at keith barker in the chats right now and then uh press enter and then i will see it hopefully and then i can go ahead and take that all right let me go ahead and bring up a bigger view of the camera ah yeah it's me and it's great to have you and let me just minimize this and take that out to there and then move something over here all right and so i just have the questions right here a little easier for me to see him this way so that's it for this quiz this recorded version and the edited version thanks for joining me if you want to participate in the live quizzes we have them every single sunday pacific time at 11 am i'd love to have you there meanwhile have a great day and we'll catch you in the next live event i'm out of reasons [Music] and i wanna tell you straight just

Channel: Keith Barker

Views: 3,165

Rating: 4.96875 out of 5

Keywords: ccna, cisco, 200-301, Cisco CCNA, Cisco Certification, ogit, Keith Barker, ccna 200-301, ccna exam, cisco ccna 200-301, ccna training, cisco certifications, ccna study, ccna certification 2020, ccna 200-301 questions and answers, eigrp routing protocol tutorial, eigrp configuration, eigrp protocol, eigrp keith barker, eigrp feasible successor explained, cisco ccna certification, ccna exam questions and answers 2020, ccna exam preparation, ccna study tips

Id: awrTEt60Lok

Length: 26min 32sec (1592 seconds)

Published: Sun Jan 03 2021