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Okay, so let's summarize what we have just discussed. All network nodes are configured

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with the default gateway. Without default gateway, your node doesn't know how to get

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out. The default gateway specifies which node to use to address external nodes. And you

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can use IP route show to show the default gateway. Static routes can be needed in some

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cases to define a route to a network that is not behind the default gateway. This is

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something that you will find in complex networks where multiple networks are connected by multiple

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routers. You could do that in a runtime using a command like IP route at 192.2.0.0.74 via

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10.0.0.10. So that will add the custom route to the 192.2.0.0.0 network via 10.0.0.10 where

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10.0.0.10 must always be a network address that is accessible on the local network.

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You can also configure persistent static routes. On Red Hat, you easily do that using NMTUI.

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And on Ubuntu NetPlan, static routes are added as a property of the network card in the NetPlan

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YAML file. So you would use routes and then you would use two with the IP address of the network

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and via with the IP address of the local node that needs to be addressed for reaching this

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specific network. Let me show you. So IP route show is what I want to do first. Here we can see

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all the routes. And there is a default via. That's the default route that I need to get out

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on the internet. And we also see the local network and the local network on the device

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ENS160. That's the direct attached network. That doesn't really count. I can use IP route

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add 192.168.30.0.24 to add an imaginary network. And let's do that without the typo. And then I

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need via 192.168.29.3 for instance. And IP route show is going to show that the route has now been

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added. Obviously, this serves to nothing if the network does not exist. So I can't test,

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but I can show you how to do it in NMTY where I'm using editor connection edit. And there we have

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routing where I need to select edit and I need to select add. So what am I going to add? Well,

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192.168.29. No, not 29. 31.0.24. And the next hop, that's the computer on the local network that

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will take me there. That could be four. And that is good enough. So I'm clicking OK. And I'm going

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to activate just the usual way that we have seen before with NMTY. Hop, activate. And then we use

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back. We get out of here. And I'm using IP route show. And what do we see? We see the new route

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being added. And how about the old one? Well, remember, anything you do with the IP command

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is non-persistent. And that means that when your network interface is restarted, reinitialized,

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or whatever, you lose the configuration on it. And that's what just happened.