3.11 Linux Networking Part 1

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all right. Hello, And welcome to command line Basics. This is Lin. It's networking one. I'm Christopher Heller, and let's begin.

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So are learning objectives for this video only the have config command or the nets that command and learn the L S O F. Command. These are very important to be able to use. The networking resource is the network commands for Lennox in order to connect to the Internet and other machines as well.

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So pre assessment which command is the best way to find your I P Is it a net step? Be nbt step C l S o f or d I have config.

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The answer is D I have config. This is for interface configuration and very useful for Lennox to be able to determine what your I P addresses. You could see your Mac address and use it to help troubleshoot any networking issues that you may have

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the nets that command. While it may give you your i p, it lists any open network connections, and it's it's not the best way they just find out if he quickly nbt Stat is used for Windows machines and the Alyssa left is used to list open files.

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So I have config like we were saying before, This is used to show the network configuration for the interfaces on your Lennox machine. And it's very similar to the i p config command that you will see for windows.

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And, uh, we can also use it Thio create a new I P address on an interface or to disable or re enable an interface as well.

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So we can use the eye of config the interface name, and then add toe add an address. You put a network mask on that as well, and then we can also use I have config the interface and down to bring the interface down and likewise we can use if config interface up to re enable that interface.

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So let me give you a quick demonstration on my Lennox machine.

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I'm in the show on the type I s conflict

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and look at that. So we have to interface is right now I have e n s 33. This is my interface for the Internet and then I have the l o for Luke back in her face. You can quickly tell this is the loop back because of the 1 27 years or one I p. Address.

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And if you're not very familiar with I P Networking or Luke backs and you know private I P addresses, I recommend looking them up

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because in your cybersecurity career, you're very critical in order for people to understand what should should not be ratting on the Internet and how these addresses air stored and managed so highly recommend doing some research on your own if you're not familiar with them.

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So as we can see my Internet, my I p address his 1 91 681 81 54 I have a leopard mask of slash 24 1st cider notation,

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and this is my broadcast address. It's one,

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and you can also see my Mac address for this interface pretty useful so we can use this to really take a look and identify any kind of trouble shooting that we may have with networking.

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All right, so nets that what this does it it displays information about the Lenox networking, and it will show any open network connections that we may have in the background. And then on top of that, we can also show are writing table with the dash are switch. And if you're not familiar with Radic tables is they'll

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used to help

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determine which interface and where should send information for I P addresses. It's not sure exist,

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so ah, that is what is used to help connect to the Internet.

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So let's go back to this Lennox machine I'm gonna take That's that

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and we're gonna see a whole bunch of information

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on Let me see. I'm not sure if I have anything open right now.

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Let me open up a Web site, actually real quick. That way we can use this to see

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while we're waiting for that, I'm gonna do

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knits that

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Nash are.

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And we can see our ratting table for this Lennox machine.

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And we have our default Gateway

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000 And it says, Just send it out. The NS 33 interface Pretty useful.

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All right, now that we have Firefox open in the background and we're on the Lenox Mint site,

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I'm just going to do next step on its own,

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and there is a whole bunch of text that once it's let's just put that into less,

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and as you can see, we have a whole bunch of different addresses and the local address in the foreign address showing that we have Ah,

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there were connections open.

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So we have cloud proxy. We have this website. We have all sorts of different ones and these air connected to the Internet over TCP. As we can see,

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this is very useful toe help Try and track down any malware that maybe existing on your machine. If it's calling out to a command and control centre, it's going toe having established connection so we can look through the nets that command and identify any unknown or unwanted connections that are coming from your machine.

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All right, we have L s O F. Also, this is a list Open files. It shows flowers that are currently being accessed across a network or being used, and it usually shows a lot of system usage, so there'll be a lot of noise, But,

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you know, we can use it to crept through and really find something that we need in order to be able to, uh,

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health. Determine if some somebody's *** kissing a file they're not supposed to you or from malware is, you know, utilizing these files.

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So it's it's useful. So we're gonna do Alice O F

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First we gotta exit at a less now this do l S O F.

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And we know that there's a lot of system files coming through here, So

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let's see if we can find fire fops. So we knew, Rip. Aah! Dash I

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Firefox

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look at that. There's a whole bunch firefox that is being used right now as an open file. So this is very useful. Be able to be comfortable with If you're looking for and trying to find things that maybe shouldn't be open

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on your machine

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aren't supposed assessment. The if config command cannot be used to change your i. P. This is true or false.

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The answer is false. You can use the I have config command to change your i. P. This is the most preferred way to do it and you're probably gonna have to run it as route because you are manipulating the hardware directly. So it's important to be ableto you understand how to use the eye of config. See your I P address. See you Mac address and that

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help troubleshoot that if you're not able to connect to the network

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so important to be confident and understand how to use these commands from the terminal