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Hey guys and welcome back. Now so far throughout this skill we have been using these deprecated

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and outdated commands. The commands we saw so far were IF config as well as the ARP

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and lastly we just saw the root command. Now all of these commands ultimately are now replaced

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with the IP command. So really in modern terms if you want to make changes to your interfaces,

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display or update your ARP cache or to display or update your routing table you really aren't going

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to be using any of these tools unless you happen to be on a fairly older distribution. And the IP

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command does not just replace the functionality of these three commands it can also do a whole bunch

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more. So why don't we go and explore this command and see how we can actually begin to use it then.

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So what I will do is I will clear my screen. Now you will recall we used the IF config command and

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we can see things such as the IP address. Now like I say we can pull out the same information

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using the IP command. Now the IP command has a lot of options. If we want to get IP address

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information the command is going to be IP adder. So if we say IP adder show and hit enter we actually

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get the same information albeit it is presented a little differently. So we can see here from the

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IF config we actually can tell the interface and then the inet command or rather the inet keyword

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tells us the IP address. In this case here it is presented a little bit differently but we can still

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see the interface in this case the ethernet interface and all the related information and

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within this information we can still see our inet address. One of the main differences is that the

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address here happens to use what is called sidernotation that is your slash 24 mask whereas IF config

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actually tells you the network mask using the format of 255.255.255.0 but ultimately we can get

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the same information we can tell which interface has which IP address just like we could with the

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IF config command and again here the look back is the same. Here is this interface with the IP

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address again with sidernotation slash 8 mask. Now remember we could use the IF config command to

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actually make modifications with respect to our interface configuration like I say we can do the

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same thing with the IP command. This time when we want to make a change say for example to an IP

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address we would say sudo ip and we'll say adder because you want to modify an address and now

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I'll use the keyword add and from this point here I can just add in my new IP address I'll say 192.168.0.50

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as we did before as opposed to using the notation of 255.255.255.0 I will use the sidernotation

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to slash 24 and I'll specify the interface that I want to target so I will say dev enp0 s3 and if

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I hit enter so now if I do my ip adder show notice here is that on this interface we still have our

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original IP address but we also have a global secondary IP address and that IP address is 192.168.0.50

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just as we specified so one big difference to note is that when we happen to update our IP

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address using the if config command the IP address ultimately deletes and replaces the old

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configuration whereas when we're using the ip adder command by adding an IP address we have just

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added a secondary IP address and didn't actually delete this one so if I wanted to delete this IP

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address I could just add a whip and I will use the keyword del and hit enter if I now do ip adder

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show suddenly that IP address has been removed once again so realistically if I wanted to change

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this IP address to 50 I would add it as 50 and then I would delete my IP address of .65 now again

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once I do this I will drop my connection so I'll hit enter and my connection drops because

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I'm connecting over ssh so I'll just go back to my virtual machine itself open this I will log in

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go to terminal emulator I'll say ip adder show and lo and behold this interface has effectively

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replaced the old IP address with this new IP address and notice this is no longer a secondary

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global IP address so I'll just quickly change this back so I'll add this type in my password

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open I've mistyped this that should be en okay and I will delete my .50 we do an ip adder show

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and the ip address is back to the way it was before now if I wanted to make a change to the

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interface such as maybe setting the promiscuous flag as we saw before remember with the if

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config outputs within the particular flags we could effectively change this to add the promisc

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flag we can do the same thing with the ip command this time we will use ip link I'll say sudo ip

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link and then I want to set and then specify my interface that I'm targeting so enp0 s3

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and I will say promisc on so the effect here is if I happen to use the deprecated command

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if config we can now see we've actually modified this to be promiscuous but alternatively we could

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say ip link show and within here we can see the interface and the promisc flag is indeed set and

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once again if you want to reverse this we could just say promisc off and to enter ip link show

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the promisc flag has now been removed again now if I want to be able to view my routing table as

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opposed to just using the root command what I can say is say ip root show and within here we are

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seeing our routing table we can see the default route is via 192.1680.1 that is my home router

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and we can see my local network of 192.1680.0 slash 24 and if I wanted to find out some

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ARP information let's maybe say the MAC address of my gateway here as opposed to using the ARP

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command I could say ip ne show ne for neighbor so if I actually hit enter here we can see here

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this is the ip address and we can see the layer 2 address i.e the MAC address is this one right

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here so we can identify this directly via the ip ne show command now if I wanted to delete a particular

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entry I could say ip ne del for delete and then I would specify a particular entry let's say 192.1680.51

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and then specify the device which is dev enp0 s3 that is the interface we're targeting enp0 s3 if I

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hit enter oh of course have to do a sudo to make a change and I do ip ne show notice now the ARP entry

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has actually been removed from the ARP cache now similarly if we want to actually add a new root

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to our routing table manually via the ip command we can see sudo ip root and we will add and I'll

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just add 192.168.50.0 and make it a slash 24 mask and I will use the keyword via to be able to specify

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how do we actually get to this remote network well we know the way we get to a remote network

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from our local network is via the default gateway so what is the ip address of the default gateway

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it's 192.168.0.1 so if I hit enter now and I say ip root show we can see here we have added a new

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entry into our routing table and again if you want to delete this I could just change this

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keyword from add to del we will now be updated ip root show and suddenly that root has been removed

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once again so as we can see here a lot of what we learned with respect to if config the ARP command

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and the root command all of it is very very relevant with respect to the ip command this command gives us

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a whole suite of tools to control these different features and functionalities but like I say the

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ip command gives us even more than all those three prior tools together so that is us for the ip

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command I hope this has been informative for you and I'd like to thank you for viewing