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Cisco CCNA certification proves your professional worth. It tells prospective employers that you can handle the day-to-day work of running a mid- to large-sized Cisco network....
Cisco CCNA certification proves your professional worth. It tells prospective employers that you can handle the day-to-day work of running a mid- to large-sized Cisco network.

The two-exam CCNA process covers lots of innovative features, which better reflect the skills and knowledge you'll need on the job. Passing both exams is your first step towards higher-level Cisco certification, and trainer Jeremy Cioara has mapped these CCNA training videos to the 640-816 test. This CCNA training is not to be missed.

Here's how one user described Jeremy's training: "By the way, Jeremy Cioara has to be by far one of the BEST Cisco trainers I have ever had the privilege to learn from overall. He not only keeps your attention but his energy is contagious and he provides the information at a level where you grasp it rather easily."

The last day to take the 640-816 exam is Sept. 30, 2013. After that date, the only ICND2 exam available will be 200-101. CBT Nuggets has a training course for the 200-101 exam here.

All trademarks and copyrights are the property of their respective holders.
1. Review: Rebuilding the Small Office Network, Part 1 (33 min)
2. Review: Rebuilding the Small Office Network, Part 2 (28 min)
3. Review: Rebuilding the Small Office Network, Part 3 (23 min)
4. Switch VLANs: Understanding VLANs (16 min)
5. Switch VLANs: Understanding Trunks and VTP (39 min)
6. Switch VLANs: Configuring VLANs and VTP, Part 1 (35 min)
7. Switch VLANs: Configuring VLANs and VTP, Part 2 (39 min)
8. Switch STP: Understanding the Spanning-Tree Protocol (28 min)
9. Switch STP: Configuring Basic STP (21 min)
10. Switch STP: Enhancements to STP (29 min)
11. General Switching: Troubleshooting and Security Best Practices (29 min)
12. Subnetting: Understanding VLSM (18 min)
13. Routing Protocols: Distance Vector vs. Link State (26 min)
14. Routing Protocols: OSPF Concepts (30 min)
15. Routing Protocols: OSPF Configuration and Troubleshooting (39 min)
16. Routing Protocols: EIGRP Concepts and Configuration (32 min)
17. Access-Lists: The Rules of the ACL (27 min)
18. Access-Lists: Configuring ACLs (34 min)
19. Access-Lists: Configuring ACLs, Part 2 (48 min)
20. NAT: Understanding the Three Styles of NAT (20 min)
21. NAT: Command-line NAT Configuration (35 min)
22. WAN Connections: Concepts of VPN Technology (33 min)
23. WAN Connections: Implementing PPP Authentication (34 min)
24. WAN Connections: Understanding Frame Relay (28 min)
25. WAN Connections: Configuring Frame Relay (30 min)
26. IPv6: Understanding Basic Concepts and Addressing (34 min)
27. IPv6: Configuring, Routing, and Interoperating (23 min)
28. Certification: Some Last Words for Test Takers (13 min)
29. Advanced TCP/IP: Working with Binary (25 min)
30. Advanced TCP/IP: IP Subnetting, Part 1 (55 min)
31. Advanced TCP/IP: IP Subnetting, Part 2 (22 min)
32. Advanced TCP/IP: IP Subnetting, Part 3 (19 min)

Review: Rebuilding the Small Office Network, Part 1

Review: Rebuilding the Small Office Network, Part 2

Review: Rebuilding the Small Office Network, Part 3

Switch VLANs: Understanding VLANs

Switch VLANs: Understanding Trunks and VTP

Switch VLANs: Configuring VLANs and VTP, Part 1

Switch VLANs: Configuring VLANs and VTP, Part 2

Switch STP: Understanding the Spanning-Tree Protocol

Switch STP: Configuring Basic STP

Switch STP: Enhancements to STP

General Switching: Troubleshooting and Security Best Practices

Subnetting: Understanding VLSM

Routing Protocols: Distance Vector vs. Link State

Routing Protocols: OSPF Concepts

Routing Protocols: OSPF Configuration and Troubleshooting

Routing Protocols: EIGRP Concepts and Configuration

00:00:00

We're now into the final routing protocol that we'll talk about in this CCNA video and that is EIGRP. EIGRP is CISCO's direct competition to OSPF. It is, unfortunately, proprietary. EIGRP is without a doubt in my mind the best routing protocol on the planet if you have CISCO routers everywhere and your corporate policy does not prevent you from using proprietary protocols. A lot

00:00:30

of corporations really steer clear of that. So we are going to look at as we go into this video why I think that the good, the bad and the proprietary of EIGRP. We will then go into the configuration of EIGRP, look at features like auto summarization, how we can set up on our routers and will replace our whole network that's currently running OSPF with EIGRP.

00:00:49

We'll even I believe go into some of the summarization features of EIGRP, just like we did with those OSPF; kind of take a step beyond CCNA and then we'll verify everything to make sure it's working correctly. Now EIGRP is the last routing protocol we're going to talk about so we have to answer the big question of why initially.

00:01:11

Why would I use a proprietary routing protocol over OSPF or over RIP. Well first and foremost, EIGRP is the only routing protocol in the world that allows backup routes. Now I want to make sure I phrase that correctly. Backup routes are allowed by every routing protocol as in if this goes down it will fail over to this. But with

00:01:36

EIGRP backup routes are remembered. Here's the idea. With OSPF, let's say OSPF or RIP. When they find the best way to get somewhere, they take that best way and they put into the routing table and then they forget about all the other paths that were once there, all of the back ups. So if the primary or the

00:01:57

best way that's in the routing table goes down, OSPF and RIP have to rediscover or relook at the network to find all the backup routes and then find the best one of the backup routes and put that into the routing table. Not with the EIGRP. EIGRP uses backup routes in something known

00:02:17

as the topology table. So whenever it finds the best way and that goes into the routing table, it says, oh yeah router; it speaks to itself. It says, if you ever lose that best away, I've got a perfect backup right here. So EIGRP is running along, life is good, the router is just sending packets, you know, humming along and all of a sudden wham, you know; a tractor outfront hit's the primary link to the internet.

00:02:43

EIGRP detects the failure and immediately says shum. Here is the backup route, no real calculations are necessary, it just says I've got it right here because I tagged this as a backup route when we initially calculated the routing table. You can see that little dual algorithm there. Dual stands for diffused

00:03:04

update algorithm. What it is, it is just the engine that runs EIGRP. With OSPF, the engine is known as SPF, it's the algorithm, that the guy who created OSPF, his name is Dijkstra created. The problem with OSPF and the SPF algorithm, is that it is very hard on your router's processor. So as your

00:03:26

router is chunking out that routing table to find back a path, it is increasing the processor load on there. With EIGRP, dual is much easier on the processor and memory. So that's the number one reason why you choose EIGRP, the only protocol to remember backup routes. Second reason is that it's easy. CISCO's goal

00:03:48

with the EIGRP was not to have a super complex protocol, but they wanted a protocol that could do all the same things as OSPF, but be easy. Meaning take the easy to configure aspects of distance vector like RIP. RIP was really easy to turn on. Take those features and combine them with

00:04:07

all the advanced features of link state and get a simple config. Third reason you'd use EIGRP; flexibility and summarization. With OSPF, now think back what was the only place we could summarize in OSPF. At the ABR, at the area border router between areas.

00:04:30

Well in EIGRP there is no concept of areas, because you can summarize whenever and wherever you want. I'll actually do that in this video as we get into the configuration, I'll show you, this is how we go under into interface and just throw in a summary route wherever one and technically I should say create an area boundary.

00:04:49

Fourth, EIGRP is the only one that allows unequal costs to load balancing. Every protocol, even static routes, allow you to do equal cost load balancing, one packet here one packet there. EIGRP can actually take a network, analyze it and say well I've got, you know, say I've got two routes to the same network.

00:05:13

Some routers, a little LAN over here and router 1 right here is trying to decide and over here it sees a T1 line, which is a 1.544 megabits per second and over to the right up here, it sees half TI line, which would be 768 kilobits per second; that's exactly half of T1. Every other routing protocol in the world would say you are the best my friend and you go in the routing table. And

00:05:40

this one which you see here is a backup, it will just be unused, thrown away. So that would be idle bandwidth that's just sitting there. Now with other routing protocols you can tune in and you could actually lie to the protocol and go into the interface and say the bandwidth of this interface is such and such and you know make it exactly equal to a T1 line and every other routing protocol would send one packet here and one packet here, but the problem with that is that it has to drag this T1 down to a 768k speed, so that it can equally distribute the load. So the point is you just can't load balance over

00:06:17

unequal cost paths with other routing protocols. With EIGRP, you can set it up in such a way where you can type in a variance command and say, well I'll take a variance of two, which says exactly half. At that point, the router will load balance across links that are half as good as the primary.

00:06:38

Now I don't want to get to deep into the variance command, but that will say, the EIGRP will say okay well I notice that I have a 768K link here and a 1544K link here or 1.544 megabit link. This is exactly half. So I'll send two packets on this link for every one

00:06:56

that I send over here, on equal costs load balancing. By doing that you are effectively combining these into one logical link and using that bandwidth to its best, so the backup doesn't just sit there as idle bandwidth which you're paying for but not using.

00:07:12

Five, I mentioned that are already, combines the best of distance vector. That's the easy to configure side of it and all the advanced feature of link state. Six and you've got to throw this in here. Supports multiple network protocols. I would say maybe eight

00:07:29

years ago this was a cool feature, maybe even longer than that, back when we were using protocols like IPX/SPX and Apple Talk. EIGRP could support them all. Nowadays all we use is TCP/IP and that you know, I guess you could say it's still a feature but just hardly anybody uses it.

00:07:49

Now let's get into how EIGRP works. EIGRP routers maintain three separate tables, a neighbor table, a topology table and a routing table. When you first start running the protocols, the neighbors will discover each other and just like OSPF, EIGRP discovers neighbors and uses the hello protocol or a hello message to say, hi are you online and exchange hello messages between them. Now EIGRP is not as strict as OSPF with what

00:08:22

neighbors it can have, so it can more easily form neighbors, but once the neighbors are formed they will exchange routes. Now all of those routes go into a topology table and this is EIGRP's road map of the network. It will remember all of the best routes and all of the backup routes in that topology table as little flags. So for example, let's say

00:08:45

well this network isn't very redundant, but let's say it is. We've got a link right here, so router 1 has two ways that it can get to the 10.1.2 network. The best route will go into the topology table and be marked as and this is getting in to some of the terms, a successor.

00:09:09

Successor, that's like the primary route that is going to be chosen. And let's talk about the other table, that one gets moved into the routing table. That is the one that will be actively used by the router. Now router 1 also notices that it can go through router 2 and then through router 4 and get to this network. And it says, you know what, let's go in and

00:09:30

add that guy into the topology table. So I'll have the 10.1.2.0 network over here and I will mark that one as a feasible successor. Now I know, I know that these terms can be kind of confusing at least for myself when I started thinking about them, let me finish writing there. Successor I almost think

00:09:56

about like a throne and I think oh well the successor to the throne. So that would be a backup right. Well you have to kind of change the logic. The successor is the one who is, this is the way remember it, is succeeding; they're the best. You know, I am very successful

00:10:11

you know, they're successful in what they do. So the successful one ends up in the routing table, that's the primary. Feasible successor is the one that stays in the topology, but it gets flagged; I put a little (b) here. It gets flagged as the backup. So if life is good and going along and all of a sudden wham the bomb

00:10:31

hits and this this router 1 to router 4 link dies, this immediately drops out of the routing table as the successor because it's down, EIGRP says I've got that feasible successor and slide it right in there. With a little tuning, EIGRP can support something known as sub-second convergence.

00:10:52

Meaning your network recovers in less than a second and it does take some tuning to get there, but that's the kind of level you can reach. Now let's get into configuring EIGRP. I have the same topology set up as I did when I configured OSPF, but now we're going to convert it to an EIGRP environment. So we'll start

00:11:12

off on router 1 up here and the first thing I am going to do is go into router 1 and turn off OSPF; no router ospf one, good bye. I'll then go in and do router EIGRP; oops router EIGRP question mark, and you can see autonomous system number. Now you might remember with OSPF, this number was the process

00:11:37

ID. In EIGRP this represents the system that you are in and unlike OSPF, it must be the same on all the routers in your network. So if I go in here and type in router eigrp 10, which I'll do right now, I have created the autonomous system ten and all the routers in my company have to be in that same autonomous system, otherwise EIGRP will say, oh you're not my company, I don't need to change routes with you. So once we're under the router EIGRP process, we

00:12:10

turn on EIGRP in the same way that we do every other routing protocol. So I'm going to type in show IP interface brief, this is my internet router. I've got the 192.168.1.1 and that's my internet link. I don't want to run EIGRP on my internet link or else you know I could form relationships with my internet service provider if they happen to run EIGRP. It would be very doubtful, but you never

00:12:34

know. So I can type in network 192.168.1.0. Now remember, one of the criteria that CISCO wanted to meet, was they wanted to make this as easy to configure as RIP, but have all the advanced features that link state protocols have. So here we are at the network statements. If we were in

00:12:59

RIP, this would be all we have to type; we hit the enter key and it starts running on any interface that starts with 192.168.1. You remember, think back, RIP you have to type in classfull networks. Meaning, whatever the default class of network is. So if I had 10.1.1.1, interface, I would type in my network as 10.0.0.0 enter, because the 10 network is a class A network. Now right here I'm typing in network

00:13:32

192.168.1.0. It will work if I hit enter, but watch this. I hit enter and it says or hit question mark. I can either hit enter and just use it like I'm using RIP or I can allow wild card bits. Now wait a second, that's an OSPF thing. You better believe it and that's

00:13:51

what EIGRP can do. You can go in and say I wanted to use it as simple as RIP or I want to use it you know with the complexity, and I should say complexity and flexibility of OSPF, because with OSPF you can really get specific as to what interfaces you would like to enable EIGRP on. So

00:14:11

I hit enter and I am done. EIGRP is now sending hellos out to the 192.168.1 interface up here at router 1. Let's hop down to router 2. Router two, I am going to get into global config mode. You want to know something, you can't hear me type anymore, can you.

00:14:32

That's because my wife bought me a brand new keyboard. It's awesome, it's an Apple keyboard. Have you seen these things, these things are like razor thin and you can, literally they are super thin and you cannot hear me type. You know it was, I'm sure a little selfish motivation on her part not to throw her under the bus. I am sure she had a great heart and everything. But when I'm in

00:14:56

here and I'm a typing, I'm slamming on the that keyboard and it's loud and she's oh you type so loud come on, and so this keyboard you can't hear me anymore. Anyhow, so I am going to type in, no router ospf 1. I'm turning off OSPF, killed the neighbor. Now I am going to type in router

00:15:13

EIGRP 10, to be in the same autonomous system. On this one let's do a show IP interface brief and there's my 192.168 network. So I'll do network 192.168.0.0, question mark, and there's my option for wild card bits. Oh that's so helpful. If I were using this with

00:15:33

a RIP, I would have to type in a unique network statement for every single one of these; 192.168.1.0 enter, 192.168.10.0 enter, 192.168.20.0 enter. Here I can just say 192.168.0.0.0.0.255.255, which again says I care about 192; I care about 168; I do not care what comes after that. So I will automatically

00:15:59

run EIGRP on every interface starting with 192.168 and right there we can see a neighbor relationship has formed, a new adjacency. I am going to type in show ip eigrp neighbors. You have to spell neighbor. Okay, I'll go back and do a show, hang on; show ip; I spelled EIGRP wrong, eigrp neighbor. It must be this new keyboard.

00:16:34

Alright so there we go, we've got the neighbor, we see the address 192.168.1.1, that's our router 1. I can see the interface I formed a neighbor on, I can see how long that neighbors' been running, I can see the whole time; whole time is how long it believes until that neighbor is dead.

00:16:52

By default, EIGRP says hello once every five seconds. So if the neighbor stops saying hello for any amount of time, you notice that the hello timers 11 seconds, 10 seconds, oh backup to 14, that's because this guy is saying hello once every five seconds. Hello, as soon as this guy receives a hello, it's starts the countdown.

00:17:12

It says if I don't hear another hello from you in 15 seconds, a.k.a. Hold down timer, you are considered dead and I will no longer use your routes and that's why you should never hopefully see this hold timer go below 10, because if it does that means you're missing hellos. You see it go down to 10 and back up because it received another hello. SRT, I won't get too deep into this stuff, but

00:17:35

that stands for source round trip timer, that's how long it takes to get to the neighbor and back. And that helps gage how long it should be waiting before it expects a hello. Now over here H, that is the most unknown column to anybody in EIGRP. I challenge you to find what does H stand for and I'm serious.

00:17:58

Nobody really knows. I can tell you what that column is, it is a list of the neighbors and the order it was received. So for example, if router 2 gets another neighbor, which it will, it will be H1 or and then two more neighbors will be H2 and H3. Those are the order it learned about the neighbors, but nobody knows what H really stands for. I know somebody suggested

00:18:21

hop count, but hop count, your neighbor can only be one hop away or no hops away otherwise you're not neighbors, you're remote distant cousins. So anyway mystery; hop. So I am going to go over to router 3, let's get that guy running; no router ospf 1, we are killing that guy, router eigrp 10, go into there; network and let's check out router 3. Okay he's 192.168.3 and 2. So I'll , let's do 192.168.0.0 and we'll use the wild card bat bits. That gets

00:19:02

it running on all the 192.168 networks and poof it forms a neighbor, that's fantastic. And this one is the one that has all the loop back interfaces. So we can advertise those as well and that way I can also show you summarization with the EIGRP. Let's do network, 172.30.0.0 and we'll add in 0.0.255.255 as our wild card bits, so it automatically runs on all of these interfaces and advertises them to the rest of the network. Super, so at

00:19:31

this point I should be able, well I'll stay on router 3 to do a show ip eigrp neighbor and there's my neighbor I learned about. This is router 2 that is router 3's neighbor. I can do a show ip route and I should be learning at this point D routes, D as in dog.

00:19:51

D stands for EIGRP, because E was already taken by the external or EGP external gateway protocol. So CISCO said well let's use D. So all routes learned by EIGRP is going to be represented with a D. Now you can see right here 192.168.20.0, 192.168.1.0 are all in the table and there's all my loopbacks and so on, but I want to show you something.

00:20:20

Let me show you something. I am going to go over to router 2. I am going to do a show ip route, prepare yourself. Wait a second, where's all the loopbacks? 192.168.30.5 and four and seven where did they all go. Ah, hah. Look at that guy, 172.30.0.0/16. What we have experienced is my least favorite feature of EIGRP. It is a feature known as auto summarization.

00:20:57

What EIGRP does, is any time you have a network that is advertised across a boundary that is not the same network, it will auto summarize. Let me give you an example of that. Right here I have a network, it is a class B, 172 dot; oh I still need to fix that. Good grief, it's 172.30 networks, right. You guys have seen that. Wow I just moved up my screen a little bit but that's alright; 172.30.0.0, that's the network said this represents. That's a class B network and that one class of addresses.

00:21:34

Now up here I have a class C network, 192.168.2. Remember class C addresses start with 192 and that goes to 223, so it's a class C network. Over here class C network. So when I advertise some, it's actually technically called a discontinuous network, a network that is not of the same type or same class as this network across that boundary. EIGRP thinks it's doing me a favor and

00:22:02

it will say; Well I'll tell you what, I'll auto summarize that back to its default class B boundary. Remember by default, 172.30 is a class B network. Let's get my screen moved up here. It's a class B network, so it will auto summarize back as if it was a class B network all over again, that's a class B subnet mask. Now I don't like that feature.

00:22:33

Whenever I hear anything in auto, in CISCO that's auto, I think I auto not use that. No auto feature is good or I should say very very few of them are. Now let me give you another example. Up here in router 1 I had 10.1.1.0/24 and 10.1.1.2.0 and and 3.0. Now I've subnetted those with classy subnet masks, but when they are advertised over here this is a discontinuous network. I am not advertising it over

00:23:01

another 10 network, so EIGRP would auto summarize back to this 10.0.0.0/8, because it thinks it is doing me a favor and just auto summing them up. Now some people like that and that it's very distance vector protocolish to do something like that, there's other protocols that do that like RIP, but I don't like that. I like control over where my

00:23:24

summary routes go because you know what, I could come up with a much better summary route than 172.30.0.0/16 because if I use that it kills the whole 172.30 range; because all these routers believe router 3 has everything to do with 172.30. So I am thinking I need to turn off that feature and here is how you do it.

00:23:48

Holy cow, was I typing in, you can see what I was typing in for a little bit. Forgive me, I hope not; I've got to review this video and make sure it looks okay. Okay, so where was I? Oh, auto summarization. The way that we turn it off, router eigrp 10; is I can type in no auto summary. I just think no auto, no auto that's what we need to type. It resets

00:24:16

the neighbor relationships and will reform them, says summary reconfigured. I am going to go up to router 1. Router eigrp, got to do on all of them, no auto; router 3, router eigrp 10, no auto, turn that off on all of them, no auto summary. So that will reform all those neighbor relationships and now look what happens.

00:24:38

I go over router 2 and I see, I do a show ip route, and I am now getting all the more specific routing information from that router. It does not auto summarize that into 1/16 block, that's good. Now let me go back and show you how I can inject a manual summary route. I had to pause the video there for a moment, to make sure I didn't

00:25:01

cut anything off from my screen. It jumped around and I didn't, that's good. So I'm going to go to router 3 and actually let me stop right there and first mention, if you are a CCNA candidate I have talked about everything you need to know for CCNA. For the EIGRP, I am about to show you a cool CCNP concept, but again very simple and it's a way that you can make your network much more efficient. I am going to go on, we're going

00:25:28

to the place where all those routes came from; router 3. Show ip route, I can see that I've got all those directly connected, 172.30.6. Now you remember if you watched the OSPF videos, that I was able to summarize at the ABR. In the EIGRP I can summarize it anywhere. All I need to do

00:25:47

is go under the interface that I want to send the summary route out of. So on router 3 I want to go underneath serial 0/0, because that's where I'm going to be sending the summary route out of. I am going to go serial 0/0 and I am going to type in ip eigrp; oh hang on, ip, wait a second.

00:26:15

I jumped ahead of myself, ip summary address, good old context instead of help. For EIGRP, that's the protocol that I want to do. What autonomous system? Autonomous system 10. Do question mark and it says what do you want your summary route to be. I'll do 172.30.0.0. Now in the last video on OSPF, we figured out the best summary mask for the 172.30 networks would be 255.255.248.0 and that would summarize zero through seven. Now I know we added eight in there

00:26:51

and we'll see how EIGRP handles that. I'll put 255; it's going to hit the question mark, 255.255.248.0, it's asking for that summary mask. Now I'll do space question mark and if you want you can tune the administrative distance, which is the believeability of that summary route. I don't

00:27:09

need to do that so I'll hit enter and now it's going to create this neighbor change. It kind of downs the neighbor and comes back up and says a new summary is configured, new adjacency is brought up. I am going to do, go over to router 2 now and do a show ip route. Look at that, there's my new summary route that encompasses zero through seven and it automatically advertises eight as a separate network because it realizes that's not encompassed in my summary route. Now I want to show you one more thing

00:27:40

and this is going to be a massive concept. What I mean is how this affects your knowledge of routing, not so much a big unbelieveable concept. Right here we go. Look at that. You see in the router that is sending the summary route, it says I have 172.30.0.0 that is a summary route that I typed in and I'm sending all traffic that is sent to that summary route to Null0. Null0 is the garbage can. What? That means any traffic that it gets that matches this summary route, the router is going to automatically send to the garbage can. It's going to drop that

00:28:20

traffic. Now why would it do something like that, well thing about this. All of these routes have a very specific subnet mask /24. When we create a summary route, let me put that up here 172.16.0.0/21, that's our summary route, that encompasses zero through seven.

00:28:41

What if this one didn't exist, what if our router, router 3 had 172.30.0.1.2 three, five, six and seven and we said oh well that's alright; let's just create a summary route for all of those and, you know, we'll just not use dot 4 anywhere. Well the way EIGRP works is if they gets a packet for the 172.30.4 network, it will start asking other routers with these things known as query packets and it will say other routers can you find a way to the dot 4 network and they will say I don't know. They will start searching the whole network causing all this traffic to try and find a route to a network that doesn't really exist. So what

00:29:21

this Null0 route does, is it says you know what if you get a packet for something you don't have a more specific route for then threw it away. Here's what I mean, you've got all of these routes in the routing table. Notice this one, six, seven and the router organized these at

00:29:42

its own will, whatever it thinks it's going to use first. So we've got this organization right here. These are all more specific subnet masks. Rule number one of routing, it doesn't matter what routing protocol you have, what you're running, is if it has a more specific subnet mask, it will use that.

00:30:01

So here's what I mean. Router 3 gets a packet from 172.30.3.50, looks at it's routing table and says ah 3.0, I've got a match. Needs to go out and loopback 3 interface, but then it looks and says, oh wait, I've got another match 172.30.0.0/21, that includes 3.50. That really represents zero zero through seven dot 255. So 3.50 is included in there. So it looks and goes well I am not going to use that one because I have a more

00:30:29

specific route. The better the subnet mask, the more specific the subnet mask, the better the routers. So this will never be used as long as it has a more specific route right here. The only time you will actually use this route to the garbage can, is if one of these more specific routes that don't exist and that means the network doesn't exist. So that's the idea behind

00:30:52

that Null0 route and that idea of specificity in those subnet masks is big. That is the core of the EIGRP routing protocol. As you can see EIGRP is far easier to configure than OSPF in multiple areas and all those kind of things and as you get into the more advanced CCNP curriculum, you will even see that ease come out more and more, that ability to summarize on any interfaces is a big one when you're looking for good features in a routing protocol. So we saw the reasons that you would look at EIGRP

00:31:26

as a good replacement for your organization. That was the fact that it never throws away routes. You can summarize at any point in the network, the algorithm it uses, which is known as DUAL, is far more efficient than the OSPF routing protocol and it is the only one I can load balance over on equal cost paths. We saw EIGRP auto summarization, which is

00:31:49

a feature that I don't like. EIGRP will summarize networks back to their classfull boundary any time you advertise them across a discontinuous link. The best thing you can do for your network is to go in and type in no auto and put in manual summary routes wherever you need. Last but

00:32:08

not least in no specific order, we saw the EIGRP configuration and verification. Simple commands router EIGRP and the autonomous system followed up with your networks, verified by doing a show ip eigrp neighbors and show ip route. I hope that this has been informative for you and I'd like to thank you for viewing.

Access-Lists: The Rules of the ACL

Access-Lists: Configuring ACLs

Access-Lists: Configuring ACLs, Part 2

NAT: Understanding the Three Styles of NAT

NAT: Command-line NAT Configuration

WAN Connections: Concepts of VPN Technology

WAN Connections: Implementing PPP Authentication

WAN Connections: Understanding Frame Relay

WAN Connections: Configuring Frame Relay

IPv6: Understanding Basic Concepts and Addressing

IPv6: Configuring, Routing, and Interoperating

Certification: Some Last Words for Test Takers

Advanced TCP/IP: Working with Binary

Advanced TCP/IP: IP Subnetting, Part 1

Advanced TCP/IP: IP Subnetting, Part 2

Advanced TCP/IP: IP Subnetting, Part 3

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16 hrs 32 videos

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Jeremy Cioara
Nugget trainer since 2003