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This video we're going to discuss static routes.

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I've been asked a number of times about to study grants.

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Are you able for example to have a multiple study Grotz configured on a Rodda are you able to have multiple

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default Rantz configured on a router.

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Can you mix default Trotz and static Grotz what's the effect of all of the above.

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In this example we can get to configure static routes on Rato one and to test connectivity to the loopback

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of wrote a five we have a two router three and wrote a four in the typology and they configured with

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different subnets rodder two is configured with IP address 10 1 1 2 on the interface Radi 3 is configured

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with 10 1 to 2 on the interface and a Foy's configured was 10 1 3 2 on this interface or Lenk.

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So you just wrote a one.

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What are we going to test.

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Is connectivity to the loopback of route of 5.

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So from road a one is it able to ping the loopback of wrote a five.

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So after the moment when not paying the loop back out of 5 we get timeouts.

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The router is not able to ping the loopback wrote a 5 show IP router shows us the writing table.

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What youll notice is that it only contains connected and local Roths there's no route to 5.5 to 5.5

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de-bug IP packet.

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As an example will show us what happens when the Rodda tryst paying that address so I'm going to ping

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5.5.

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5.5.

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And repeat it once and let's see what the output looks like.

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Notice unrideable the rodded doesn't know where to rock the packets.

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And again that's because there's no route to the destination.

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There's also no gateway of last resort set on the Rodda.

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So it has no way to get to this IP address.

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We could configure a route as follows.

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So an exact match on the route and pointed to a train that wandered 1 to 2 which is routed to show IP

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right now shows us that route in the rotting table.

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Second the router not paying the loopback of wrote a 5.

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And the answer is yes it can.

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I'm going to disable IP domain look up here to speed up trace route.

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So let's trace to the loop back of route of 5.

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Notice it's going via 10 1 1 2 which is routed to and then it gets to run a 5.

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What happens if I configure a static route like this and pointed to two routers three which way will

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the traffic go.

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So let's have a look at the writing table.

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Show IP wrocht shows us two entries in the writing table.

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There are two ways to get to the loop back of route or five.

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So if I trace to that loop back Notice it's still going via route to.

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In other words it's going to 10 1 1 2.

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And the reason for that is because this entry is more specific than the sentry rodders when deciding

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where to run traffic.

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Look at the longest match of a route this route is a 32 but match.

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This is a 24 bit match.

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So the traffic's going to go via train 1 1 to.

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And we can prove that by doing a trace route if we remove this route from the writing table

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and then do a trace again notice the trace route is going via 10 1 to 2 but that's because we only have

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this route in the writing table.

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If we created another static front like this

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via route a full

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which way with the traffic go so show IP route shows us the two entries we've got to slash 16 slash

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24.

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So when we trace to route a five notice it's going via Rodda three because this is a longer match.

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That is a longer match than this.

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So Rodda three is preferred rather than a full.

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But again if we removed

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that dropped from the writing table someone to remove the sentry

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so remove the static ROFFT

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Now when we look at the writing table we only have the sentry so traffic will go via 10 1 3 2.

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In other words it's going to go via road for

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if I add a more specific product of let's say slash 20 for

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going via router three again

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notice the traffic goes via Rotto three.

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And if I use a more specific route such as this

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going via a router to rather

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notice the traffic goes viral it to show IP route to shows us those routes they slashed 28 to rot is

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more specific than a slash 24 route which is more specific than a slash 16 raht.

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So remember with static routes and this applies to other routing protocols as well more specific matches

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when.

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So what happens if we add a route like this

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same mosque as rodded to configure it to go to rodders 3.

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So show IP route.

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Notice the difference in the writing table now weve got two entries for the same route.

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So when we trace to the loop back now notice its doing load balancing traffic is load balancing across

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both parts and thats because weve got two equal entries in the running table.

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Its a show run include Robert

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these two rats are going to be used for load balancing because they are the most specific and they are

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the same length.

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These two will be ignored.

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But if we copy that and add an entry

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going to 10 1 3 2 2 Rotto for the writing table shows us three entries.

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Now if we trace to the loop back.

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Now notice its going to load balance across those three routes.

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You need to be careful with this because sometimes depending on the router the load balancing may actually

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not be true but for CCMA level we assume that it load balances as follows.

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So show run pipe include dropped things to remember most specific entries when if there are multiple

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entries with the same rot and same mosque such as these three the ratable load balance across those

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paths equally.

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So in other words equal cost load balancing all load sharing enjoyed this video if it was a benefit

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to you please like it and please subscribe to my YouTube channel.

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I wish you all the very best.