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In this lesson, you'll learn how to monitor network interfaces.

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So it starts by getting a list of available interfaces.

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IP link show is the command that you should use.

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If you want more in-depth information about the interface properties, you can use lshw

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minus class network.

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Don't use ifconfig anymore.

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That's a legacy command and is really not supported anymore.

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To add non-persistent runtime interface configuration, you can use ip address add and next use ip

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address show to see it.

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The legacy eth tool utility was used in the past to change device settings such as auto

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negotiation, port speed, and more.

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That's a utility that nobody uses anymore.

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Let's check out the relevant utilities.

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So to start with, there is ip link show, and ip link show is showing information about

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your network links.

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Lo is your loopback interface.

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That's not really an important one.

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It's the internal networking set that is used by applications that use TCP sockets to communicate

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with one another, which is an old-fashioned way for inter-process communication anyway.

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In my case, ens160 is what it is all about.

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This is the interface that has a so-called BIOS dev name and that holds the current configuration.

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So ens160 is revealing information about the physical location of the interface.

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It's also known by its alternative name, enp2s0, where p2s0 stands for PCI 2 slot 0.

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That's actually the physical location.

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You can also find the MAC address of the interface and other properties such as the maximum transfer

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unit, which on Ethernet is set to 1,500 bytes in total.

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If that is not enough, well, you can use lshw.

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Lshw by itself is a utility that shows information about all the hardware found.

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And it's giving you a lot of results, so many that you probably don't care about all of

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them, and you better use lshw-class to filter down on a different category of results.

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So minus-class network will show you network-related information only with all the different capabilities

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and more information like the capacity and the clock speed and much more.

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So that was detected information that is coming from your driver.

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Now, if you want to change your network interface non-persistently, let's start by using IPA.

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IPA is showing that I'm using 192.168.29.11 on this interface.

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And I can temporarily add an interface by using IPAA, which is short for IP address add.

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IPAA always needs a device, which in my case is ENS160, followed by the IP address that I want to add.

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And then I press enter, and IPA is showing the secondary IP address.

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And ping 10010 is showing that it's even answering.

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Now, in case you think that is cool, don't forget that after a restart of your network interface, it will be gone.

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So if you want to make the change persistently, you need to continue and watch the next video,

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in which we'll talk about persistent network configuration.