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Okay, let's do sudo ipa. You don't really need
sudo. But hey, I'm doing it automatically and doesn't hurt.

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I have my ENS160 which
is in the state of UP.

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And what else do we see? It's dynamically assigned.
That means that there's a DHCP server behind it.

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And this is
the inetv4 address.

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It also has an inetv6 address which
is the ipv6 address. But as I

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told you before, that is not
really something that is used a lot.

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So to verify that we can reach
out to google.com I use ping google.com and

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that's all. I'm not going to check
my hostname resolution and my routing table.

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00:00:47,380 --> 00:00:53,210
I would only do that if pingongoogle.com is giving me a
failure because then you want to know what's going on, right?

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And the option is that you get
hostname could not be resolved. So let's do

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a ping on something that doesn't exist.
Then you can see the error message.

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Here you see the error message name or service not
known. That means typically that it's not available in DNS.

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And if that happens for a server that should be
available, well then the next test would be to ping 8.8.8.8.

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Everybody on the planet is using
it. It's a Google DNS server,

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it's very much available and
use it as a connectivity test.

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If you can ping 8.8.8.8 and
you cannot ping DNS names, at least

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you know that the problem is
DNS related and not routing related.

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Next SS Tul which is
showing services currently offered on

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my system. No need
to do sudo for that.

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00:01:48,760 --> 00:01:55,760
Now when I want to do NMAP the then I
do need sudo nmap and let's do sudo NMAP on localhost.

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Now funny thing is that when we
use sudo NMAP on localhost it's only

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scanning some of the most common ports
and that's why it doesn't find everything.

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NMAP has a ton of options.
Go explore them if you want

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to learn more about all
the rich possibilities of this utility.