This is one of multiple videos that demonstrate trouble shooting scenarios in campus environments.
In this typology I have four switches configured switch one and switch to switches switch three and
switch four or axis switches.
Now to keep the topology simple I haven't got cross-connect configured here.
Additional access switches in my s.a.a course I show you a larger topology but for this troubleshooting
video we'll keep it simple.
We've been told that PC 1 in the network is not able to ping PC to typology I'm using Broder's to simulate
PCs.
So let's test that can Rato one PC one ping 10 1 3 2.
So it looks like the pings are failing.
PC one is in violent two and PC two is in villans three show IP raht writing is disabled on those Rodda.
But it does have a default gateway of 10 to 1 2 2 2 5 4.
So we should be able to ping the stifled gateway so paying 10 to 1 2 2 2 5 4.
Yes we can.
Can we paying the land three on the default gateway.
Yes we can.
So PC one can get to the default gateway.
What about PC to see his brought it to acting as PC to show IP interface brief.
We have tendered one to treat or two configured show IP raht default gateways tendered one to treat
or to Firefall.
So can we ping that default gateway.
Looks like we can't.
So there seems to be a problem somewhere between PC to and switch one.
Let's check on switch for connected to PC to.
So this is which for sure IP interface brief.
It's got an IP address of 10 1 1 4 paying 10 to 1 1 2 4 4.
That works.
That is the default gateway of the switch.
So the switch can ping it's default gateway kenned ping tendered 1 2 3 2 2 5 4.
Yes it can.
So we've established that there's basic connectivity between the switch and the default gateway.
Let's have a look at our trunks Shasho interface trunk
trunking is enabled on gigabit 00 That's the interface between search for and switch to show CVP neighbors.
We have a relationship to switch to but we've already proven that that works by being able to ping the
default gateway villans are allowed across the trunk Can you spot a problem already in this typology.
What's the problem based on that single command.
Something's wrong noticed.
00 is a trunk but it's only allowing villans 1 to 2 and 4.
But the PCs and vi learn three.
So let's have a look at the configuration of the gigabit interface.
This interface is configured for trunking and we're not restricting any V lines but we only permitting
villans one to two and four across the trunk show interface gigabit zero or one switch port.
What's wrong here.
Can you spot the problem we're looking at the output of the interface on the switch.
What's wrong.
The port is enabled.
It's set as static access it's configured to use access of helium 3 but notice this key word something's
wrong.
Show run interface can give it to 0 1.
So the port is correctly configured to be in violent 3 but chose villaine brief will show us that there's
a problem.
Can you see the issue.
Where is villans 3.
So be careful.
You can have a port configured in a villain and not have that villain in the villain database.
If that's true the port is essentially disabled it won't work.
No traffic is going to be sent through that port because it belongs to a rogue a villain.
This is often the case when Vitti is used.
If you delete a LAN on another switch that update has propagated to other switches in that apology V-P
removes the villain from the villain database but doesn't take the port out of the villain.
This port is manually configured to be part of violent three but violent three doesn't exist in the
violent database and hence the switch port command is showing us that that's an active villain on the
port.
That's a problem.
So show VTB status is configured as a server the switch so let's create a violent three show the land
brief.
Suddenly now we see Port gigabit 0 1 configured in violent three.
And when we look at the switch port we see that it's in violent three.
That looks good.
So Ken wrote it to ping its default gateway.
We may have to wait a while for things to update.
But notice they the pings started succeeding Ken wrote a one now ping right to acting's PC too.
Yes it can.
So we've successfully result of the issue in this typology.
Be careful.
A port is statically configured in a villain but that requires the villain and the villain database.
When using stented villans if the villain is not in the villain database the port is essentially in
a rogue villain and is not used.
Traffic will not be sent through that port.
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I wish you all the very best.