When it comes to the networking, there is probably nothing that cannot be done with Linux.
Linux is used to build all sorts of networking systems and appliances, including firewalls, routers,
name servers, network attached storage nest boxes and on and on.
So just the subject of networking is a farce.
So are the number of commands that can be used to configure and control.
It is so much closer than here, so we will focus our attention on just a few of the most frequently
used ones.
So the command chosen for examination include those used to monitor networks and those used to transfer
files.
In addition, we are going to explore the ssh.
Ssh.
A program that is used to perform remote logins.
And in this lecture you will also learn ping traceroute ftp w get ssh ftp netstat netstat.
You will also learn traceroute.
And you will also learn IP and etcetera networking commands.
So let's get started.
So let's actually firstly start with the mining and monitoring the networks.
Even if you are not a system administrator, it's often helpful to examine the performance and operation
of a network.
So first let's start with the ping command here.
So the most basic network command is a ping.
The ping command sends a special network packet called actually, let me write it down.
It's actually so long here, so we don't need that anymore.
And here the ping command.
Uh, sense a spatial network packet.
Ping.
Ping Command sends a ping.
Command sends the spatial network packet named ICMP echo request.
So, uh, this sets the two specified host.
So most most networks devices receiving this packet will reply to it, allowing the network connection
to be verified.
And it's possible to configure most network devices, including Linux host to ignore these packets.
And this is usually done for security reasons to partially obscure a host from a potential attacker.
And it is also common for firewalls to be configured to block ICMP traffic, for example, to see whether
we can reach to our telecom.
Um, one of our favorite sites we can use ping command ping oxley.com and here actually it open at the
browser to I want to show you how our website looks like here.
And here, as you can see here, we are sending packets.
And after that we will, uh, the Linux will show us the statistics of, of this pag pages here.
oxley.com.
And this is our website.
Versus tuning.
Digital forensics, Kotlin, cybersecurity and etcetera.
And this is also our YouTube channel here.
So let's look here.
And as you can see, it still continues to sending pings here.
So after now, we're going to interrupt with Control C and after when we interrupt it, we see the statistics
here transmitted received packet loss and time, 51 seconds.
And here we are seeing average minimum maximum.
And so after it is interrupted in this case, after the 52 packet by pressing Ctrl C pink prints performance
statistics, as you can see here and it properly performing network will exhibit the 0% packet loss.
So in this case our packet is and web server host is good and a successful ping will indicate that the
elements of the network, its interface cards, cabling, routing, the gateways are in a generally
good working order and we also have the trace route.
So the trace is route here.
So.
This trace route.
Actually, let me see here.
Yeah.
Uh, though this trace route program and some systems use a similar to trace path program.
And in this case we will the default is trace route is installed.
So you don't need the trackpad for now.
And the tracer program lists all the hops.
Network traffic takes to get from the local server to a specified host.
For example, to see the route taken to reach our telecom.
You will do this trace route and trace route and here you will enter telecom trace route.
And here we will see what it will take.
So firstly, it's a local and then two, three, four, five, seven.
Now after output, I will tell what it will show us here.
And our our actual our web server has the firewall Cloudflare Firewall.
And that's because maybe we will not get any results or any meaningful results here because.
Our Web domain has a.
However, and it's filtering the request here.
And let's actually try Google.com.
It's actually Try udemy.com.
So that's how the traceroute program works.
So in this output, we can see here the connecting from our test system to our udemy.com traversing
16 routers.
And actually we can also use the IPS for this um, here, 0.0.1.
And here, as you can see here, it's just showing, showing us one, which is the localhost and it's
our localhost here.
So.
Uh, we in cases where the routing information is blocked, we can sometimes overcome this by adding
either the, uh, the adding either.
Here actually adding either T or uppercase T or uppercase E command here.
So operation is not you have privileges.
So you will also use the pseudo for in order to use this.
And as you can see here, we reached the telecom here and just in the two traces here.
And actually let's try the E parameter here.
E option here right now and here.
Let's see what will happen.
We are waiting for now.
And here, as you can see here, we are reached in the ninth hop here and that is how our traceroute
program and actually you can also use man traceroute to get more information about the traceroute program
itself.
Their description printer resource packet, restore networks and description parameters, options and
etcetera.
And let's go to our next tier which is IP command.
So this IP program here, IP program is a multi-purpose network configuration tool that makes the use
of the full range of networking features available in a modern Linux kernels.
So it replaces the earlier and now it deprecated Ifconfig program with IP.
We can examine systems, network interfaces and routing table.
So in next lecture you will learn about the IP and netstat command.
So I'm waiting you in next lecture.