Original subtitles

OK so let's see if we can complete the slab together.

The first thing we need to do is configure and optimize features of P

That means that we going to configure it use or P on the core such as in the topology core 1 and core

to

call one in court two of these switches that are configured with TV Land routing as well as a layer

three IP addresses for the various villains.

In other words they have these SVM eyes or switched virtual interfaces configured so they're going to

be used as the default gateway for the pieces.

Now we could configure the pieces to use switch one as a default gateway or they could use switch to

as their default gateway.

In other words we could configure pieces in VLAN 10 to use this IP address as the default gateway and

perhaps for devices and VLAN 20 this IP address as the default gateway.

The problem with that is if this piece he has core one configured as its default gateway and core one

goes down pieces and VLAN 10 will no longer be able to connect it to devices and other villains because

they default gateway has gone down.

So the idea with H.S. or P or hot standby running protocol and other protocols such as your IP or virtual

right a redundancy protocol and AGL BP or gateway load balancing protocol is that they create a virtual

router or virtual default gateway.

So the ideas you run these protocols on the core switches and a virtual router or virtual default gateway

is created for the pieces.

If a one of the core physical devices goes down it's not a problem because of the other physical device

will do the writing on behalf of that virtual router.

So we want to configure H.S. or p on these two core riders so that we have redundancy in case one of

the physical riders goes down pieces will still be able to use their virtual default gateway.

So on call 1 let's start with V land 10 the command to use is standby and you specify a group number

you can do load sharing of traffic within a villain by using multiple group numbers for this unique

course however we're just going to use one group no the group number could be the same number as your

villain number but it doesn't have to be.

I'm simply going to use group number one on all the villains to show you that to the group number is

not specific to a villain group numbers can be in this range.

So we type of standby group number one IP because we want to have H.S. IP configured for IP version

4 and we specify a virtual IP address

now in this example we want to optimize it use IP that means that we want call 1 to be the HS IP active

router for v lands where it is of the spanning tree route.

Notice for this villain it's become active because there's no other router or switch configured for

ages IP.

But the idea is the switch is the spending tree root for villains 1 10 and 30 we going to want it to

be the H.S. IP primary for those villains we don't want the switch to be the HS IP primary or active

router for VLAN 10 because it means that traffic will traverse across these links to get to the default

gateway and in the same way we don't want switch one to be the HS IP active router when switch to is

the spending tree root for VLAN 20 because traffic would have to traverse this way to get to the ages

of P default gateway so hence we are going to match it just IP active routers to villains and a way

to ensure that is to change the priority of the active Rota the higher the priority the more likely

that that route it will switch will become the HS IP active forward a more active router default priority

is 100 standby 1 preempt allows us to force this switch to become the H.S. IP active router when it's

up.

So as an example if it went down so you turn off call 1 CO 2 would become the HS IP active right a while

core 1 is down but when you turn on call 1 and it boots up again pre-emption will force it to become

the HS IP active right once again so show standby we can see that we've got a group configured on VLAN

10 state is active a virtual IP addresses this a virtual MAC addresses this.

Now this is the H.S. IP well known mac address this is the group number group number is 1 because we

created a group of 1 This is a hexadecimal number if we had created group 10 the MAC address would have

ended in zero a a being hexadecimal for 10 if we had credit grouping 11 it would have been a b b being

hexadecimal for eleven active rowdies the local Rata pre-emption is enabled stand by right it is not

known yet we haven't configured switch to so switch one doesn't know about another HS IP Roorda property

is 200 on this side if we type show Stand by we see nothing because we haven't configured H.S. or P

on the switch yet.

So on the same v land bill and ten standby make sure that you use the same number on both sides.

IP.

Same IP address.

In other words same virtual IP address.

Now we could specify a property here.

We don't need to because the default is already 100 but if we type show run and have a look at the configuration

on VLAN

10.

Notice the property is not displayed because it's the default property.

The Rada has become a standby.

I just hope he goes through different states and state is stand by.

So show standby.

Shows us that for this group the local switch is a standby switch do the come on again here.

Pitch 1 one or call 1 is the active rota Code 2 is the standby Radha will stand by switch it's a play

3 switch but it's acting like a rotor so forgive me if I use the terms interchangeably a virtual IP

address is that notice MAC addresses the same stand by road it is the local Rata of road it is call

1 property is this that is the default on the side.

We've got an active rota being the local Rada and it's now learnt about CO 2 being the standby Radha.