Right now, it's time to talk about something very important, which is the pseudo should comment,
OK, or the Sudworth by now, what is it?
So if I type mentioned like this.
You can see that we will get that, execute a command as another user.
OK, so here, if you have the description, it allows a permitted user to execute a command as the
super user or another user.
And the most cases is the one somebody who is on, which is the root command.
By the way, the road user, I mean, and you can see that there is security policies to do a lot of
options for the pseudo and so on.
You can read more if you are interested, but I want to show you the most important things.
No, I am the one to use.
And by the way, I am using that on US cloud.
So by default, the Ubuntu user or the Ubuntu machine, it has the option to use.
And this user is a power user, which means using the pseudo.
It will not ask you any question.
It will not ask you or prompt you for password.
So you can just type Pseudolus and you can see everything is here as a student.
Right.
All right.
Now, this is by default, by the way, so that's why it's better to have another user, not the default
user, because this is a very dangerous user.
This is anyone type pseudo or anyone has an open door type pseudo and it has the privilege of fraud,
which is something very dangerous.
OK, so for now, let's use the Zuckermann.
The Zuckermann.
Actually, if I type Mansor, you can see that this is to change user ID or become a Subaru's, which
means if I type so.
I've been type throughout.
You can see that I will go to the road user, but it will ask for a password.
The password for the open to that, by the way, and after I type it to see if I am authorized or not.
But actually, I don't have that's what I will type control the controls it.
So let's clear the screen door.
I will not use to.
On if I will do Sudoku.
OK, dish out without dish for now.
So to do so, it wouldn't let this use up to go to this specific user by default.
If I didn't provide any user, it will be rude by default.
OK, so I want to go to the root user and using the pseudo permission.
So if I type it like this, you can see that this time I am the root user.
And again, by the way, I didn't prompt they didn't bring me any password or something because this
is in to ask for your machines or I they called it.
It is the Ubuntu here.
It is the power user.
OK, so this is the root.
OK, contrary to exit from the machine, which is the rotation.
OK, now let's return to that.
Now if you will notice after I go to the SUDA to the root user, I still in the home directory of omentum
and we still have the environment variable of Ubuntu.
Now I don't need that.
I need to go to the so I need to go to the root user and I need to go to the home directory for road
as well as I want to import the environment or export the environment variable upwood.
So I would use the Desh.
It means two things.
Go to the home of this user who are going to which is in my case, root and export all the environment
very best for this user, which is in my case, because by default, if I didn't provide any user,
it will be so presenta.
So you can see currently I am who I am if I type about kashrut, which means the home directory of the
road.
And it worked 100 percent so far.
So good.
All right.
Now let's have a look on the Sudworth fight.
If then ETSI Sudworth, you can see that we have this file here.
You can see that we have Sudworth also towards the D.
So if you want to edit, the suit was fine.
It's better to have it on this one.
The deal this is the best practice, by the way.
But anyway, we are just viewing only as we don't need to change anything in this once.
So let's have a look here.
You can see that.
Yeah.
Permission denied.
Why is that?
Because this fight actually is protected by on the root can do that.
Imagine if anyone in the system and user in the system can do that.
So we are -- up.
But by the way, sorry about the language.
OK, so if I typed don't shift one, shift one, which is the exclamation mark now I will use this to
run the previous command, which is this one as a root.
And by the way, you can see the state read-only.
But because I am the truth, I can't edit it, it's OK because I am king right now.
OK, now you can see that this is the format, the difficult environment, difficult man, whatever
secure bath for the default behavior.
These are environmentally driven, by the way, or very busy.
So you can see that here is the privilege we want.
So for the road user, we have all Equant, all old and the old.
Now, what are all of these old?
OK, now all which means the terminal or that terminal I am opening on or the concern.
If you are interested, you can read more about it.
But what is most important, which is oil, which means all user.
So run this as all user and run this as all user and here all, which means all comments.
So route user can run everything as everyone and for every comment.
OK, and this is the same thing for the admin groups.
But by the way, you can see that there is a Bessant symbol here.
OK, shift five.
So this means that the admin group, any member inside it, will be able to run all, all, all the
same thing.
Now, this is the same thing for the pseudo, by the way.
So you can see that here is a person.
So this is a pseudo group, by the way, we already saw that this quote from this for now, if I type
ID or groups, whatever, you can see that the groups that object to inside it, one of them is Sudam.
We already saw that.
So let's again open that.
So it was fine.
So you can see that for the student group, it is all, all, all and all.
But you can see that we have this argument, which is nobody with anyone inside the SUDA, the group
will be able to run all the commands for as all user or as all group from all Terminates or Hitwise
or whatever without prompting any basswood.
OK, all right.
And actually it's better to edit this by not using them.
Actually we have the wide pseudo command.
OK, so why should pseudo and actually it requires you to, as you can see, the mission to unite,
to cause you to be a student.
And we already mentioned that we don't need to talk about it anymore.
Why it needs I mean, why it needs the permission.
OK.
So here.
You can see that we are losing, by the way.
No, no, I don't know why, because this is what they prefer anyway, but it's not bad.
I'm not saying it's bad.
It's up to you what you prefer.
OK, so here you can see that I can't eat anything I want.
But by the way, if you cannot hear the name of the fight is the tape, which means that this is to
save to safely secure your flight.
So, by the way, if you for example, so you can see there, it's easy to do as the engine.
So no change has been made, have been made.
So by the way, if you open the Sudworth and if you if you -- up here, actually you put some mistake
or something.
Actually, the whole system will be done or the whole system cannot use to do anymore.
So, for example, if you don't have an explicit access to the root user, then you are done.
Actually, unless you have the physical access on the server, then you will go inside it as a single
mode, which means as a rule, then added to the fight, which is the root fight.
It is to do what is fine.
I mean, then return it to its original or modify the mistake that you done.
Then everything is returned back because actually you are using them immediately.
But if you are using Vasudha, which is this command here, even if I type like this, so imagine with
me.
So you have for example let's.
But any arbitrary value by the way, this is a mistake.
Yeah.
So let's save that.
And actually this is bad.
You can see that I'm just watching I think, but I'm using the power to do so by pseudo.
It will not -- you up so you will see the way this inter you can see that.
Yeah it show me etsi so the word syntax error syntax error nearline.
Twenty one.
OK, so what now.
So listen up for example.
So you can see that the options are either to the was file again or exit without saving change to suit
or quit and see changes to do are fine.
And this is being done now.
Actually this is not just danger.
This is stupid.
So if you do that, quit and save the change.
Even though you got a warning, there is a syntax for undecidable file, then maybe you are stupid.
Sorry for that or it is a mistake.
And if it is a mistake, you are forgiven.
It's OK, no problem.
But actually I want to eat, which means it should wash it again or exit without saving.
So eat so you can see here again.
Oh yeah.
Which is this line and I want to delete it.
Just delete everything.
Yeah.
And click that and.
Yes.
It said this and said, oh, we didn't get any problems, so you can see that no errors shown here.
All right, so everything is work but fine, which means there is no mistake.
But if I eat it so you can see if I eat it, then that suit was filed immediately like this.
If I make the mistake here, you can see that.
Yeah, it's you can see that it is because I am I can edit it immediately.
So you can see I said that the whole system cannot use to do anymore.
Why is that?
Because there is a syntax actually in that sudworth.
So anyone try to use Sudo with something, it will not be working at all.
So unless the solution for that, unless you have a physical access to the server, which means to open
it as a single mode.
So if you are using the cloud, you are actually not turn back.
Well, actually it's not like that.
You can just attach the podium and attach it again or change the fights there and then attach it that
actually there is a work for that work around it.
There is a solution for that, but it is Hajduk and a lot of work to do and you already have enough
work to do, actually.
The other solution, if you have an explicit access to the user, in that case, you can just attach
to the system as a route user and then change whatever because you are the road user, which means you
can do whatever the system and then change the necessary.
By the way, the road user.
Yeah, it is the king on the system and can do whatever it want.
But by the way, I can change its privilege so I can make it Lisboa by the way.
And we will, we will not.
And that you can read about it.
We not that in this lecture.
Alright.
Thanks for watching.