EX200 Red Hat Certified System Administrator RHCSA – Linux Graphical User Interface (GUI)

1. Basic familiarization with Linux Graphical user interface part 1.

Welcome everybody to this tutorial. Today I’m just going to go ahead and enter Red Hat. We’re not going to do any more installations or anything of a kind today. We’re jumping in but we’re easing it in slowly. First I’m going to show you the graphical user interface and then we will move on to the terminal. I first want to show you where is what approximately. Before I do all of that, I have have made some alterations to the Red Hat virtual machine. I have just assigned it more resources and you can do the same by clicking on Settings and then going to System and you have the motherboard processor acceleration at these things you can only change while the machine is down. So once you power the machine up, these changes can no longer take effect. You see I cannot do anything here. I need to turn the machine off, then make these changes. But in any case you can see that I have assigned it almost three gigs of Ram and I have assigned it an extra process, a CPU core. Hopefully it’s going to run a bit faster and this is going to be a lot smoother experience.

You can do the same if you wish, but it’s not required. I’m simply doing this to save on time. It is not a pre requirement of what we are about to do. Anyway. I’m just going to go ahead and cancel that, minimize this and have a look at this desktop. If some of you have used Mac, it’s fairly similar to it. On the upper bar you have Sound Network Manager, Power Management, Date, Username, or you can put in your real name there if you wish. And on the left side over here you have Applications and Places. So let’s click on places. Okay, captured. Click on Places so it can take you home. Documents, downloads, music, pictures, videos pretty much similar as in Windows. You can even browse the network if you want but doesn’t really we’re not going to do that for now anyway. Once you go into applications for all of your Windows users out there, this is basically like the start menu. You just click on it and then you have pretty much everything that you want. Here we have the browser, which is the default one is Firefox of course. And we’re going to see don’t open it my good man. Never mind. While it’s opening it up for the first time it’s probably going to want to do some updates or something of a kind. Speaking of which, we need to do them as well.

But first let me just introduce you. So you have the Firefox browser. Here you have the Mail client. Basically, this is for music. For photos. You have Liberal Office, which is the equivalent of Microsoft Office. You can pretty much do anything in Liberal Office that you can do with Microsoft Office as well. So no problems there. And under files if you’re wondering what this is, this is actually a file manager so let’s just go ahead and click on it to see what comes up. Excellent. So this is our file manager and I’ll just kill this red gigantic thing in the background. Close them, most of them. Most of our time we will be spending at the command line and we will be mostly dealing with the terminal. But it’s good to know it’s good to have a look at these things, and it’s good to actually be at least acquainted with the graphical user interface, if nothing else, as it is a prerequisite for using it as a desktop machine, but not a prerequisite as using for service or anything of a kind which we eventually want to be able to manage, control, install and so on and so forth.

Anyway, this is your file browser and you can pretty much go anywhere from here. If I go down to computer it’s going to take me to where some of the system files are I cannot access. Where the system files are I cannot access some of them you see there’s an X here on route if I double click on it it says the location could not be displayed you do not have the necessary permissions to view the contents of root. This is going to be a similar case in all pretty much the same case, actually, in all linux distributions. You will not be able to access certain parts of it or see it unless you have root password or unless you are using a terminal to actually view it, which is very nice, primarily because it disables 99% of viruses out there, pretty much because they cannot do anything on your system without proper permissions. So anyway you have the temporary files I don’t know you have the root files and here under VAR you have the log files somewhere just have a look at them. I’m generally not used to doing this via graphical user interface but let’s just have a look at it.

So log excellent so you have these log files that you can later on read don’t worry about it, we will go through them, we will read them I will explain to you this in far greater detail. For now I’m just introducing you to the graphical user interface, nothing else. So just go ahead and close this and go back to applications and now you have categories of applications so you have favorites and these really are pretty much the most used applications in pretty much any Linux distro terminal and Firefox and browser they are the first two and then comes the rest. So under accessories I don’t know you have some stupid things that you would use for your daily affairs. Oh by the way the equivalent of notepad in Linux I would definitely say that it’s G edit except it has a download of more capabilities and options. There you go definitely but we can use it a little bit later on but we’ll mainly be using text editors in the terminal. So you can just go ahead and close that.

If we go further down below. Okay, so documentation, graphics, nothing there. Come on internet. So nothing there. Excellent. Under Office. So here you have, like, liberoffice writer, which is word or liberoffice impressed. I think that’s the one for presentations in the Office package. I’m pretty sure that you know, to which I am referring to a PowerPoint tip of my tongue but couldn’t really remember. So liberal office impress is basically PowerPoint. If I’m not mistaken. Librao’s draws an equivalent of paint or something of a kind and Librao’s Calc, which is basically axle. If we go down further below we got sound video. Okay, so Cheese is for your webcam. Just so you know. You can utilize your webcam with cheese.

Barest is for burning CDs but you can burn CDs through via the terminal as well without any sort of problems if we go down below. Sundry okay, so we got Se, Linux troubleshooter print settings, not that important. Firewall. Excellent. So you have the graphical user interface for the firewall and if we go ahead and click on it we’re going to be prompted with a root password that’s going to actually no. Are you serious? And if I select this, okay, there will be a root password. That’s hilarious. If there wasn’t anything here, if it didn’t prompt me for a root password then I could do pretty much whatever I wanted to the firewall. I would completely disavow Red Hat, completely and utterly. Anyway, here you can but fortunately it does require the password. Here you can pretty much do anything with the firewall. And firewall in linux is open source. Its capabilities are practically infinite. You can do whatever you want with it. There is pretty much nothing that you would need that you cannot do with a Linux firewall. It’s amazing.

I don’t know, I’m sure you can find something and make me my own words, but you get the general idea. So you can decide what services do you want to allow, what ports you got port forwarding, ICMP filter, this is for pinging and so on and so forth. But look, all of this we will do later via the terminal as that is the proper way of doing this. Because on a server you don’t have a graphical user interface and you have to do with what you have primarily because graphical user interfaces are resource expensive and they waste Ram, they waste CPU and you don’t want them. Plus all the power rests in the terminal, the almighty terminal anyway. So go back to applications. Sundry, we were here. SELinux is your, how shall I put this let’s say antivirus system or a way of tightening down security internally. We will deal with that later on as it will present, as it will play a major role in this course, if you go down to System Tools, you got settings boxes and a lot of things here. But I’m going to continue talking about that in the follow up tutorial as I am running a bit of short on time here and there are a few things to which I wish to introduce you here as well. Just so you know that you can access them this way as well. And more often than not, on a desktop up, you will need to as well. Until then, I be you. Farewell.

2. Basic familiarization with Linux Graphical user interface part 2.

Welcome back everybody. Let’s just continue. So in the application section, go down to System Tools and here you have a lot of interesting things. So for example, you have a system monitor which is a very nice utility and we’ll show you an equivalent of it in the terminal, which people do tend to use quite often. So you have file systems, you can take a look at them. Them, they are listed here. Come on. There we go. So run media random Guy vbox guest editions. That is the mount point of my guest editions. That’s when it’s used 100%, which is the way it’s supposed to be. But you can also see pretty much everything else. Let’s go into processes here you can take a look at all the processes that are currently running on your system, if there was anything. Well, after a while. I know it seems when you look at it like this, kind of complicated, and you don’t know what is what. And you wouldn’t be able to tell apart a malicious thing from a benevolent thing.

Over the course of time, over when you start using it, when you learn about it, when you use it on a daily basis or something of a kind. And you pass the Red Hat certification for a system administrator, eventually you just need to take a look at this once and you pretty much know what each one of these things does. In those 1% of the cases out of 99% you have a vague idea of what that process is and then you can figure it out from there. But believe me, people can just glimpse at this and pretty much know what each one of these does relatively fast with relative ease. Anyway, in addition to that, you got the user that’s running those processes. Random guy. That is me. That is my username that I have created. Yours is probably different. I hope to God that you didn’t copy mine. I strongly urge you to type in whatever you wish. And in addition to that, we have the amount of resources that our current processes are consuming.

So you can see most of them are pretty much idle. But this one, the Gnome shell is consuming. 32% of the CPU has this ID which can be used to actually kill the process. And then we have 573 what is this megabytes, I think hold on, let me just expand it. It’s 573 megabytes of Ram, which is a fairly expensive process in comparison to pretty much everything else that is running here. However, there are better tools which we will use in the terminal and that will give you better overview of the entire situation but know that this exists. So let’s just close it, go back to our place. System Tools and there we go. So it says Red Hat subscription manager.

You can configure your subscriptions here if you want other sort of registrations. What I really want to do is go ahead and click on software and here you can actually search for different sort of packages which some backup client, let’s see, just selected and this is basically a graphical user interface for the installation of various packages of various software programs, et cetera. So you can pretty much find whatever is in the repositories here. However, people don’t tend to use this one as a Gui. But again, another one of those things that you should know that it exists and all those for example on Windows, on Android and on Mac you know how they say oh, it’s amazing, you have this store and you go there and you can download software immediately from there. Well, let me just tell you, Linux had that from the very beginning. From the very beginning. Well, maybe not the first Linux that ever came up but it’s pretty close, I am sure of it. Pretty much people have just been pulling software from the official repositories for as long as I know. So long before Windows, long before April Mac OS X and definitely long before Android Linux had repositories from which people always kept on pulling software to install onto their machines as it is a fairly secure way of doing that as all that software that is there is checked by the repository maintainers. Anyway, it’s a very nice thing to have but we’re going to use a terminal one which is fairly simple to use.

It’s called Yum and I will show you definite and I will show you fairly well how to use it. You will become proficient with it so you don’t have to worry about it. Another thing here is the system log. Now even though most people tend to do these things in the terminal, the system log here the tool, it gives you a rather nice overview of the things. So if you just type you do require a root password in order to review the logs as is to be expected. So you have various processes here of various things that have happened. You have their logs and you can see what is going on. This is especially important for troubleshooting. I would even argue that this is better than the terminal as it gives a bit of a better overview of the existing logs and then you can just scroll through them and see what is going on. Generally people take a look at messages and what was going on in general with the system itself. You just scroll up and down and take a look at these lines. They don’t mean much to you now, but they will in time just show a bit of patience. You can’t know everything from like five minutes.

You cannot learn everything, that’s for sure. Just a little bit of patience and you will eventually become proficient. Okay? So, yeah, this is another thing that I’m going to show you fairly soon, but for the time being, let’s just stick to what we have. System tools again. So you have startup applications here. You can configure cron jobs. If I’m mistaken. Or you can configure cron jobs via the terminal. But here you can also use a graphical user interface to just say, okay, I want this application to run at startup, and I want this one and I want this one or I don’t want that one. I don’t want this one.

So here you can actually create your own scripts and link them here. Just name it whatever you want. Then you browse it in the file system. You find it, just double click on it. The command will be here, and then you can even comment it if you want. That script will run at startup. This is a very common thing for system administrators. To have plenty of scripts that will run at startups. They usually carry Basic with them with like 10,000 scripts on it. Every particular script has its own thing.

Usually those are troubleshooting tools that people make for themselves. I don’t know to filter to filter certain traffic out or to boot certain services to kill certain services to start certain services sorry, not boot. And to display certain files or to display certain logs and to see the status. Of certain things anyway. That’s pretty much it as far as this part is concerned. Perhaps one more thing is Redhead access and boxes is actually for accessing other machines, so we won’t need that at a time being, but it can be nice. You can use Red Hat access to connect to their network directly from your operating system and have a look if you can find anything useful there.

But we shall deal more with these things. A bit later on here. I’m just giving you a bit of info. Down at the Utilities there are some fairly nice things, so Archive Manager can unpack pretty much anything. You know how in Windows you have to actually, I mean you have to download an unzip software. Seven Zip is free, but you have Raw or you have Wind Raw or something of a kind that you have to pay for here in Linux you can pretty much unpack anything for free. No problems. Got a lot of things here. Well, dictionary is not particularly useful to us at the moment. You get a disk usage analyzer. Not bad. Okay, so Remote Desktop Viewer is very nice, which comes free. You can utilize it, no problems. To access computers remotely and provide technical support. That can be very nice. You don’t need to install anything extra there. Up here you got disks. So I’ll just open up our disks. And there we go. We got pretty much everything listed here, so it’s 137gb hard disk. This is probably the windows one, if I’m not mistaken. No, sorry. This is XFS Linux bootable.

Down below we got other Red Hat 2. 7 gigabyte block partition. I don’t exactly know what this is, but okay, so 80 block device. This should be home. There we go. So red hat home. Let’s just see what this is. Oh, this is Swap. There we go. So we can read it. Here it’s Swap and up here it’s Root. So you can figure out how you can review your partitioning scheme here without bigger problems by just clicking. It’s fairly simple to read through it without any bigger difficulties. You can also create a disk image, restore a disk image. You can benchmark it. It provides a wide variety of options for you to play around with. I’ll just go back to Utilities to see if I’ve actually missed anything. No, that would be it. Okay, so there is one more thing that I want to show. Sorry, Utilities. Sorry. Action Overview. Excellent. So if you go to Action Overview you’re going to be prompted with this.

And on the right side you have your virtual desktop. So you can have multiple things and multiple desktops that can be very nice, primarily because it’s a space saver. So you can just switch between them. We’ll probably do that later on as we progress here. At the top center you have a search box so you can type in the approximate name of any application. So there we go. So terminal. Okay, so let’s try something else. Barreso for a feeling I misspelled it. Sorry. Bricero. That’s how it’s read. I misread it because I don’t use Brissera, I use the KD one but doesn’t really matter. I want to show you something new and something a bit different. Anyway, you can do this in the terminal, as I have said, but this is how you would search for things in your GUI interface so you could actually find them. You don’t need to know the file system by heart.

You can just use the search functionality here and figure out where is what and how to find things. This is your sidebar on the left side. So you have firefox here and some other things. This can be changed by a simple drag and drop. Fairly simple. You can even show the applications like this frequent or all. And now you can just scroll down. So this has been implemented for a while now. If you have a touch screen or something like that, I bet this could work really well. But anyway, down here at the bottom is our number one program, the holy grail of power, the terminal. So let’s just go ahead and open it. With this I shall conclude that today’s lecture. In the next lecture we will start using the terminal.

I hope that you have familiarized yourself with this desktop layout, at least to an extent, to see where is what and what can you do where. Because I remember when I was starting to learn when I was figuring out how Linux works and coming from Windows, the graphical user interface was completely unclear to me. So I went around, I learned I scowled, and so on and so forth, even though I should have probably learned the terminal first. But over the time you learn how to use the terminal, you learn how to use the command line. It is important to know how to do things in GUI, primarily because that is your reserve option. So if you don’t know how to do it via terminal in the very beginning, while you’re still learning, just go ahead and use the GUI. Don’t waste more than an hour on something. If you can figure it out. Oh, well, do it in a gui and then come back in the terminal, especially the firewall settings and stuff like that. That is quite delicate, and you need precise commands to know exactly what is going on. To know exactly what sort of traffic are you allowing to pass, and what sort of traffic are you not allowing to pass. In any case, as I said in the follow up tutorial, we’re going to jump straight into the terminal, so be ready. Until then, I bid you all farewell.

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