Okay, so let's see if we can configure this topology.
I'm gonna start off by configuring the call 3650 switch.
So this is a multilayer switch
which means that we need to configure multiple IP addresses on the switch and enable IP routing between
the VLANs. So the first thing I'm gonna do is create the VLANs, VLAN 10, VLAN 20, VLAN 30
and VLAN 100.
So show VLAN should show us the VLANS and there you go
we'll make this a bit bigger.
So again show VLAN and I'll use brief here.
Here's the command.
We can see that all interfaces are currently in the default VLAN.
We've got VLANs 10, 20, 30, and 100 configured but no interfaces are in those VLANs.
So interface gigabit 1/0/20 this is the interface where our server is now a good check to use is do
show IP interface brief and verify that the interface is up.
That helps you check whether you're working on the right interface in your lab.
This interface is up up.
So that's a good sign.
So I'm gonna type switch port access, switch port access VLAN 100, show interface gig 1/0/20 switch
port.
This will allow us to check that our configuration is correct on the interface.
So there's the show command this interface is enabled as a layer 2 port, we're using static access it's
operating as a static access port.
In other words it's an access port and not a trunk port.
The VLAN used is VLAN 100.
So that looks good.
So I now need to configure the other interfaces so before I do that show IP interface brief, we can see
that these interfaces gigabit 101,102 and 103 are currently up, show run shows us that at the
moment no configuration has been applied on the interfaces now these ports gigabit 101 102 and 1
03.
Need to be configured as trunk ports down to the switches so interface gigabit 101 switch port mode,
Trunk.
Notice you may get an error in the real world or on your switch depending what it is.
You may have to specify the encapsulation as dot1q before you specify switch port mode
Trunk that often depends on the switch.
So you may need to set the encapsulation and then you can specify the mode as trunk.
So I'm gonna do that on all three ports encapsulation is dot1q mode is gonna be trunk.
Now show run, shows us what we've done.
Notice each port is configured to use a dot01q and to use trunking.
That's correct because we've been told to configure ports between switches as trunks.
That's also best practice in a layer 2 infrastructure, so to prove that we could type show interface
gigabit 101 switch port.
Notice on gigabit
101
there's the show command, on this port
it's administratively configured as a trunk.
It's operating as a trunk, encapsulation used is a dot1q native VLAN is VLAN 1 which is correct.
So what we've done thus far is configure the three ports to the access switches as trunk ports, we've
configured the port to the server as a access port in VLAN 100.
The next thing we need to do is configure switched virtual interfaces or SVIs to enable inter VLAN
routing. VLAN 1 is the default VLAN it's currently down so I need to enable that and I need to configure
the switch with IP address 10.1.1.254/24 mask per our instructions the other SVIs
or switch virtual interfaces are gonna have these IP addresses so interface VLAN 10, IP address
10.1.10.254/24 mask, no shut interface VLAN 20, IP address 10.1.20
254 no shut, now the interfaces are coming up but from experience, I always no shut the interface
there's gonna be no harm in doing that if it's already up that's great but if it's down we are ensuring
that the interface comes up.
So there's no problem doing that just to be sure,
interface VLAN 100, 10 1 100 254/24 mask, no shut the interface.
Okay so show IP interface brief, notice we have interfaces up, notice my mistake I configured VLAN 40
that's not required and notice the SVI is down because no interface is configured in that VLAN and
that VLAN doesn't exist in the VLAN database, so I'm gonna remove that SVI.
so interface VLAN 40 is removed.
Show VLANs shows us that VLAN 40 is not in the VLAN database.
So again if I created interface VLAN 40, no shut that show IP interface brief would show me that
the interface is down because that VLAN doesn't exist in the VLAN database. You've got to have
the VLAN in the VLAN database for the switched virtual interface to come up. So again I'll remove
that no interface VLAN 40. Okay,
one thing we still need to do on the core switch is enable IP routing, IP routing is not enabled by default.
we've got to enable IP routing to allow the switch to route from one SVI to another. So as soon as you
start creating multiple SVIs and the switch is gonna be your layer 3 switch all the switch that
does the inter VLAN routing you must enable IP routing on that switch.
Okay, so at this point I'm gonna save the configuration of the switch let's configure the access switches
and then we'll be able to test whether the core switch is configured properly.