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Together we’re going to take a journey through Linux and give you the knowledge you need to be a power user, but first we must ask the question, what is Linux? Well, confusingly it depends on who you ask. In order to get an idea of what Linux is we’ve gotta go back in time. In the early 1980’s Richard Stallman, then working in the AI lab at MIT, started the GNU project with the goal of creating an entirely free and open Unix-like operating system. This all started when the lab got a new printer, but the license restricted his ability to modify the code. He had hacked earlier printers to electronically send messages to users who printed items when the printing was complete, as well as notifying other users when the printer was free to use. By the early 1990’s there was almost enough GNU software to create an entire operating system, however their kernel, the GNU Hurd, was not yet complete. Meanwhile, in the early 1990’s Linus Torvalds set out on a hobby project to develop Unix-like colonel known as Linux, and used GNU software such as GNU’s “C” compiler to do it. While a kernel on its own was useless, he ended up including GNU software with the kernel tree to release an operating system. Later, Richard Stallman’s free software foundation sponsored the group Debian to release a GNU/Linux distribution that was completely open for people to use and contribute to. Debian over the years grew from a small group of Free Software Foundation hackers, to the enormous community that is today. Due to its popularity, Debian has become the base of countless Linux distributions. Because of how open the software is, anybody to read the source code, modify it, and then redistribute it. Because of this, this is what we have now, it’s kind of a mess. There are so many Linux distributions that a common problem for beginners is what Linux distribution should I use. While there are a few distros out there that actually include its own software, one of the biggest problems in Linux is how many distros there are and the fact that a lot of them are the same distribution with new wallpapers, and icons, and everything else is the same. Ubuntu was started in the early 2000’s and is owned and distributed by Canonical. The base of Ubuntu is Debian, and Ubuntu has become so popular that it has in turn been forked countless times. Forking is a process which the operating system is used as the base of a new distribution. Ubuntu includes it’s own desktop environment called Unity, and has recently started distributing phones running a version of Ubuntu. Canonical also contributes bug fixes and other contributions upstream, meaning that they send these changes back to Debian to include in future releases. While Debian releases new versions sporadically, Ubuntu’s aim was to capture the stability of Debian, but released new versions more frequently. As such, Canonical releases two distributions a year, one in April and one in October. The naming convention of Ubuntu is year & month. So, the version we’ll be working with was released in October of 2015 and it’s called Ubuntu 15.10. Every two years in April, a long-term support version is released called LTS, which is officially supported for five years. While releases in between LTS versions are supported for only 9 months, the next LTS release will be in April of 2016. So, to download Ubuntu we’re going to go to Ubuntu.com, and when the page loads we’re going to see in the top navigation that there’s an option that says desktop. Just click on that, this is the version of Ubuntu we’re gonna be working with, and then when you get on the overview page, just click download Ubuntu, the big orange button in the main area. And on this page it’s gonna give us a few versions, so it’s gonna prompt us to download the last LTS release which was released 2014, in April. If you’re gonna be running Ubuntu on a server it makes sense to you long-term support versions because you only need to install a new version like every five years. You can install more frequently because there’s new LTS version every two years, but with a non LTS version there’s only official support and bug fixes for nine months. So, we’re gonna go with one of the nine months cycles here and download the latest stable release which is Ubuntu 15.10, this was released maybe 10-15 days ago. We’re gonna download 64 bit because that’s the processor type we’re running. You can either click the download button to download it directly in the browser, or you can click alternative downloads & torrents to view what other type of other files you can download. Now, if you’re running on a really super fast internet connection it doesn’t really make a difference. The in browser download is probably going to download just as quickly as a torrent, however if you don’t have an incredible internet connection, a torrent download is going to make a lot of sense. It’s going to download a lot quicker than it would in the browser. Now, I’ve already got my version downloaded, it took about 10-15 minutes, because I have really bad at the moment. Next thing we’re gonna do, we’re not going to install to directly onto our hard drives yet. That’s an awful big commitment to make when you you’re not really familiar with the system. So, we’re gonna do is go to VirtualBox.org, and this is a piece of software that allows us to create virtualized machines, virtual machines are a virtual computer if you want to call it that. This allows us to create different virtual machines, set them up differently, as well as star different operating systems on one. So, when you get to VirtualBox.org there’s a gigantic button here that you cannot miss. Click on that and it’s gonna take you to the download page for VirtualBox. Now, it offers different packages dependent on different operating systems. This is going to be for the host machine, and to put that it clearer terms, the computer that I’m in right now that we can see is running Windows 10, that is the host. So, I need to download VirtualBox 5 for Windows hosts, this link right here, click that it’s gonna start the download. Now, I’ve already got mine downloaded. We’re going to need these in the next few videos, so thanks for watching!
So, the last video that we’re doing is setting up an SSH host on our local machine, and it’s really simple. So, let’s go ahead and open up terminal. We need to install openssh-server. So, go ahead and run “sudo apt-get install openssh-server” I believe it is. We’ll get an error message if that’s not it’s been awhile since I did this, so. Once we have it installed you’re basically good to go, however we are going to make it a little more secure. We’re gonna change the port that this runs on and so there is an SSH deconfig file now. Let’s go ahead and run “sudo nano /etc/ssh/ssd_config” So, we can go ahead and make this more secure by changing the port and also changing the authentication stuff. So, let’s go ahead and change the port to 2212 instead of the default 22, and then we’re going to scroll down here a bit, and under authentication here we’re going to change permit root login to no, so nobody’s gonna be able to login as root. Scroll down a bit here as well, and we’re going to add a line this is allow users, and this is going to take basically a list of usernames of users who are allowed to log in through SSH. So, I’m going to make my user account able to login through SSH and this is going to restrict all other users from connecting to this machine via SSH. So, I’m going to save it and exit, gonna clear this up, and then what we need to do is restart the SSH service. So, run “sudo systemctl restart ssh” and you’re good to go. And so now if I were on a different machine here, actually let’s see if I can get my external IP address here, I don’t think I can get it through here, no. Alright, clear this. I’m gonna open up network-tools and I’m gonna do something like if you guys have seen the movie Inception, this concept that I’m about to do will feel a little little bit familiar to you. This by the way when you go to network-tools.com the IP address that pops into the input field by default is your external your public facing IP address. This is the IP address that your internet service provider gives to you. Now, actually in order for this to work, this would have to be the only machine or I would have to set up through the router DMOZ port forwarding or a host forwarding, but what we can try, we’re gonna try it anyway. I’m going to
“ssh [email protected]” and then from here I’m going to ssh into this machine. It probably won’t forward that port. So, I would have to go through my router at this point to configure port forwarding for that port 2212 in order to be able to connect from an external host to this host. If you only have one machine, so basically like the IP address of my server when I, when I go to the IP address, it goes directly to my server. It’s not configured through NAT addresses my server actually has five IP addresses, and those IP addresses go directly to my server, and that’s why I can access SSH on that server without having to configure any routers or anything. I think actually the server provider manage that in some way. So, anyway you know if I were to go into my router and configure DMOZ or port forwarding, what I was just doing would in fact work. So, thank you guys so much for watching, and I will see you guys again soon.
Hey guys, in this video it’s all about SSH. So, first what is SSH? It’s an abbreviation that stands for Secure Shell and it basically allows you to access the shell or the command line of a remote host that has an SSH server setup. So, in one of the previous videos I connected via SSH to my own server and so I’m gonna do that again, and I’m going to explain exactly what I’m doing as I’m doing it. So, the way to get connected to a remote host through command line is using the “ssh” command, and then the only argument it’s gonna take is the connection string. So, in this case it’s my username on my remote host at, and then the remote host. So, I can use this or any other domain name that points to that server or I could use the server’s IP address, and when I hit enter it’s gonna ask for my password on that machine, so I’m gonna put it in and you’re gonna see that the prompt is gonna change. I’ve actually got this machine named the exact same thing is I have my server name, so it’s nick@voltron here, and I’m on my local machine. So, if I were to go to “var/www/html” and then run the “ls” command, I’m gonna see that I’ve got a lot of directories here actually, and a lot of these are actually unused and old projects that I worked on. But, anyway, basically once you get connected all the commands are the exact same because it’s essentially just a remote Linux shell. So, I could return to my home directory, then list those files, and you’ll see that again I’ve got just a bunch of random files. So, that is how to connect to SSH, when you’re done just type exit the connection will be closed. So, that was a really short video just to recap how to get connected is type “ssh” your remote user name at the name of the remote host, and hit enter and its gonna ask for your password. So, thank you guys for watching this video. In the next video we are going to be going over some SFTP, which is a bit bigger.