Hi there.
That is Ron Hadad here again.
So in the last lecture, we have reached 2.5 of this lab and we have put all the interfaces in a bridge
and I have explained what is the benefit to use gibberish.
By the way, the hardware offload started from the router OS version 6.41.
So it's not a very a new feature.
It's a bit old.
Now let's continue the lab to do with the path number six.
Put comments on all interfaces.
Comments are very important that we should use one, we want to work with Microsoft.
Microsoft provide us a very nice facility to be able to make the comments.
So for example, if we go to here and we have Internet one, two, three, four, show what we can do.
We can say on Ethernet WAN, you can just double click here if you want and put the comment or you can
just try to click and say, I want to put a comment.
You can say here that is the wide interface.
So then the comment will be shown up over here on top of the interface.
Then you know that it's not one is the one at the fish.
Now what do you need to do?
Internet two or three and four or five?
You can just say that those are LAN interfaces.
So I'm going to make comment.
I'm sorry, love interface on it and I still have to stop it that wrong.
Also, I will do the same for this one VLAN interface, same for this one line interface, same for
this one line of the fish.
So you can see how important it is to use the comment, especially also when you are going to be working
with the firewall rules, stricter rules.
Then you can say that this rule, what it has as a function, you just put the common so you can understand
what is the function of that rule, but not only for the rules, for anything you want to do on the
mixed the the you can put comments so it explained to you because you may happen that you did something
you know it now.
But after ten days or one months or one year, you forget it.
And how can you remember that?
So with e-commerce you can remember what is the function of each of the configuration that you have
done.
So this is how you can put the comments for five or six is Don welcome to the shop and disable all unused
port by one column.
So if you go back to the router now we have my P.S. is connect now on ethernet five because and the
last point I was checking your all the interfaces are working and then I left it on Ethernet five you
can see because it has an R means running.
All right.
But now if anyone who has a computer, they come and reconnect to the rather than a do with an issue
or Internet for that he is able to join de network and he's able to connect to the internet and he's
in my lan and he can run whatever you want as a hacking tools to able to hack my network.
And that's something we really need to avoid.
We don't want that anyone who was able to come and connect to the internet on them, I rather show what
you can do.
The unused interface.
Like at this moment I'm not using Ethernet two, three and four.
So what you can do, you can just disabled them.
So how to disable them?
If you want to use it from the Mac, stick with box tool, then you can just select them, then right
click and then you can say disable.
So you have disabled them.
All right.
Now you can do that also from the command line.
And let me show you on the command line how can be done?
I have already written it before, so let me just record it so we can we can make it very fast and let
me explain it to you.
Okay.
So that is the common you can see what is saying here.
Interface Ethernet set a showing.
You find where the interface is not running so it doesn't have an R, so find the interfaces which it
doesn't have an on and make it disable.
Yes, that means disable them.
That's what the common say interface ethernet.
So all we are talking about the interfaces which are the internet interface set and then we say five
were not running.
So each mission mark means it's not running.
So all the interfaces in the internet which are not running then make them disable.
Look, if I make now after you see those interfaces one down.
So if you have many interfaces on a switch, for example from migrating just one comment like this,
you disable all the interfaces which are not running now.
How to enable them back.
All you need to do to show here disable this now means that interfaces which are not running then disable
is no means enable them.
Right.
That should be back.
Yes.
And then we can see they have been enabled.
So I will leave them now like here, like they are enabled.
And then that is all what I wanted to show about how you can disable the the interfaces.
Using one comment.
I'm going to leave for you this comment inside this lecture so you can download it and you can use it.
But number seven is done and post number eight enable loop protection on internet two with the default
settings.
All right.
What does it mean?
Blue protection.
It's something.
You can find it on the interface.
We have to go to Internet2 so that is interfaces and that we can see this want project protect.
So what is the loop protect?
Exactly.
Let me explain it to you on the graph.
So loop protect if we have, for example, this is there out of my building.
Rather this is called connected to a switch microchip switch.
And this microchip switch is connected to.
Another microphone switch.
All right.
So what you can do, you can make this interface here as a loop protected.
So what does it mean here?
Then this router will send an every integral a pocket to the switch.
Then this bucket, if it is, come back to him.
Then he knows that there is a loop happening over here and that he will disable this interface for some
time.
All right.
So that's very important to enable, especially if you are not using this spanning three protocol inside
your layer two.
Because you see, now what's what's happening is that you have redundancy now between those two switches.
Right.
So that means if the traffic come from here, that can come back to here and it can go back to here
and go back to here.
So you have a loop.
Especially if you have broadcast, for example, then it happens that you have a loop and this also
will come back to Disruptor.
So there are other we know that you have a loop.
Now, what is the mechanism to avoid having loop on the layer two is to use the spanning three protocol.
Actually spanning three protocol is the name of the protocol.
Most of the time are going to use the R STP, which is rapid spanning three protocol, because three
protocol is very old as as the version we use the rapid it's binary protocol, which is faster.
So what the rapid spanning three protocol do that when it sees that there is redundancy that will block
one of these two links.
There is some calculation on the background that happens, but it will say, okay, I'm going to block
this and refresh than all the traffic.
All the traffic would be flowing from that site to that site on that link.
This link will not be used.
Now, if this things goes down, then this link will be used and that's the mechanism to avoid having
loop.
But say that you don't have ATP enabled or rapid spanning three enabled on your layer two that in this
case you have broadcast.
So what it's important that you make loop, protect on that interface, enable that it will send that
packet and containing it smack out of the others of that interface that if the ATP is not enabled,
then the traffic will go like this and that will come back like this and we'll come back to this interface
and this interface will see it smack others coming back to him.
Then he said, I said this Mac others and this coming back to me that means that is loop here.
So what he will do, he will disable this board and he will distribute it for some time that we define
it.
So once you disable it, then you don't allow the loop traffic to come to the router.
And because if you have, for example, a broadcaster and all the broadcast, all are coming to the
router because there is some loop that they're out, you would be very high, not able to serve the
users.
So that's why it's important that you have the loop protect enable this now by default.
Loop protect is not enabled on the microcontroller and you can see here on the interface is attached
to this is the loop protect default started this off.
So what you can do you can make it on for example.
And here it was sent the packet every 5 seconds.
Only five said it was sent from internet to a packet to check if there is true.
And in case you find that it's a loop that it will shut down the interface for 5 minutes.
You see those values.
You can change them if you want.
So if you can just make it all, you see, the stuff is became on now.
All right.
In my case, I don't have now looping because I'm just connected to one mike the crafter.
So there is no need for this loop product.
But that's something you can use it for security so that you don't have a broadcast or whatever traffic,
which I'm making loop to come to your router so you can disable that interface when it detects very.
What number eight is done.
And with this point, I have explained to you about the physical security that you can do on the Mike
Decorator Show.
You have gone through different parts.
We still have one more lecture in this section and we are going to speak more about now the LCD screen,
how we can disable it and to tune it.
So because also on the mike, the craft itself, there's some like the crosses, they have LCD screen
from where you can monitor, but also you can control things.
So it's better that we you see how we can disable that.
Do not be easy for the intruders to get the information from our mike the copter or to gain access to
our microwave cluster.
So I hope that this lecture was informative for you and I will see you in the upcoming lecture.