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So for this challenge, we're simply asked to finish solving ticket 3 from RBGP

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troubleshooting

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demonstration.

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So as a reminder, ticket 3 here says that R1 is supposed to be injecting the

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207.45.145.64

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network into BGP, but it's not.

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Now, as we sort of already established, looking at the diagram isn't going to
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Now, as we sort of already established, looking at the diagram isn't going to

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do as much

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good here.

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So let's just go ahead and jump right in to router one.

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So let's go ahead and start off with a show IP BGP.

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This way we can look at our own table and we can see if we're injecting that

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network.

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So what we see here is we in fact do not have the 207.45.145.64 here in BGP.

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So probably the next logical step would be to look at the running config for B
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So probably the next logical step would be to look at the running config for B

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GP.

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So let's do a show run section BGP.

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And there's sort of two things to note here.

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First, we do in fact have a network statement here for 207.45.145.64.

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We also have a redistribute connected that's being run through a route map.

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Either one of these should be able to put this network into BGP.

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The reason for this, as I mentioned, and since we can't really see it on the
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The reason for this, as I mentioned, and since we can't really see it on the

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diagram,

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let's just verify it here real quick. If we do show run interface loop back

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zero,

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notice that we do have the 207.45.145.67 on our network card as a secondary

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address.

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So that means that we do have this network on router one.

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So let's first try to take a look at why our redistribute connected isn't

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getting it because

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clearly it is in fact a connected network.
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clearly it is in fact a connected network.

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So let's do a show route map and we'll look at that RM connected to BGP route

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map.

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And what we see is this is matching on a prefix list and then setting the

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origin to

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IGP.

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So let's take a look at that prefix list.

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If we look at this prefix list, this is literally only matching on routes that

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begin with 204.186/16
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begin with 204.186/16

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and they have a mask of less than or equal to 32.

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So in other words, once again, we're matching on the first 16 bits to 204.186

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and then the

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mask has to be between 16 and 32.

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Well that does not match our 207.

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So that means that the network we're looking for does not match this prefix

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list.

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If it doesn't match the prefix list, then it doesn't match the match clause in

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the route

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map, therefore it's not getting permitted and it's hitting the default drop or
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map, therefore it's not getting permitted and it's hitting the default drop or

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deny

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at the end of the route map.

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That's why the redistribution is not picking up this 207 network.

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Now based on this configuration, it really looks like that's not what's

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supposed to

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happen.

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It looks like just based on the BGP configuration, if we scroll back up, we see

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that there's

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a network statement for each address on the loopback zero interface.
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a network statement for each address on the loopback zero interface.

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So it really looks like the intention here is that the network statements are

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supposed

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to be bringing these loopback networks into BGP.

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So if we look at our network statement, this is a 207.45.145.64/27.

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The mask is 2552555255224, which is a slash 27.

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Now just to let you know, since we sort of cheated a little bit and looked at
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Now just to let you know, since we sort of cheated a little bit and looked at

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the running

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config for the loopback, we can actually look at this address down here and see

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that it's

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supposed to be a dot 192.

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So that is cheating a little bit to see the problem right here like this.

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Let me show you another way that we could have found that it's incorrect.

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We're going to do a show IP route and we're going to pipe this through the

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section.

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And this is something a lot of people don't know you can do, which is sort of

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why I wanted

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to show it here.

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If we hit a question mark, notice that what it's actually looking for is a
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If we hit a question mark, notice that what it's actually looking for is a

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regular expression.

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And now that we've learned regular expressions a little bit, think about this.

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We could say, show me everything at the beginning of the line that begins with

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a capital C

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for connected.

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And by doing this, I can filter my routing table to only see connected routes,

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because

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these are the only entries that begin with the C. Now, if you're wondering why
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these are the only entries that begin with the C. Now, if you're wondering why

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I did

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section instead of include, well, in all fairness, if I had done include, we

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wouldn't have gotten

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all of this, which honestly, we don't really need.

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So a plus of doing include instead of section would be not to get all of our

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codes.

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However, if we had done include instead of section, we would have missed this

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line down
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here showing us that we may have some multipathic.

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So you really just would have to make a trade off on whether you want to use

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include or

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section. But the main thing I wanted to show you is that we can do a regular

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expression.

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So if we look here at this entry, which is what we were really after for the

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204 dot 45

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dot 145 dot 64, notice it's a slash 26, not a slash 27.

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And as we discussed earlier, this must be an exact match.
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And as we discussed earlier, this must be an exact match.

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So we're going to have to configure our network statement.

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It's usually best to remove the incorrect one and then put in the correct one.

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Once this is done, let's exit our configuration and let's do a show IP BGP.

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Notice that right here, we have our 207 dot 45 dot 145 dot 64 in our BGP table,

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which

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does in fact solve this ticket.
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does in fact solve this ticket.

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This of course also concludes this challenge as well as this skill.

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If you feel that you were lacking any of the information needed to complete

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this challenge

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successfully, I would encourage you to go back and review the necessary

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sections above.

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Otherwise, congratulations on completing troubleshooting, routing protocols, B

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GP edition.

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I hope this has been informative for you and I'd like to thank you for viewing.

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