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Hello and welcome back to the official start cop series we're onto.

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And figuring Callie Lennox and we're going to be covering some Kelly Lennox essentials in this module.

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So we've got some Khalilah Central topics and also some other important concepts to help you manage

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your Daily Limits installation more effectively.

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So this is our table of contents.

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We're going to talk about the network manager, how to configure interfaces.

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We'll talk about the system, the network daemon.

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We'll look at managing users and groups, creating new accounts, modifying or disabling accounts.

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And we'll also look at configuring specific services for programs like databases, Apache Web servers,

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PostgreSQL minus Kuo.

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We'll look at SSA for remote logins.

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As well.

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So this is our chapter flow.

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So we'll talk about the network first.

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We'll move into managing users and groups, configuring services, and then managing the services.

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So we're going to talk about the typical desktop installation of Kelly Linux.

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You usually have the network manager program already installed and it can be configured and controlled

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through an arms control center and also through the top right menu.

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You will go ahead and log in.

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With our default username and password.

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I built this from the Kelly Linux virtual appliance.

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So it's the latest version.

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And you'll notice in the top right hand corner, you have this little network icon.

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Right now it says Ethernet network connection or wired connection one active.

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So you also see other things like VPN connections and you can disconnect, reconnect, you can right

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click on it and you can edit different connections.

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You can add new connections, both wireless VPN connections, IP SAC Layer two, tunneling protocol,

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anything you might need, even Bluetooth connections.

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So we're not going to do that right now.

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When I close this out.

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You can also get to the same resource from the settings menu.

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Instead of calling.

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There's all your different system options are here.

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We can go into the settings manager and control different things that you might want to see, different

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tweaks that you might want to make.

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Keep in mind from before the previous models.

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If you want to get out of your virtual environment, you can click the right control or you can press

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the right control key on your keyboard.

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You can actually modify that inside of VirtualBox if needed, if you're running it virtually.

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So the default in our configuration will typically rely on the HDP, the dynamic host config protocol

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network manager gets preinstalled and configured through Vietnam during default desktop installation,

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but configuring it by default depends on the DHCP server to get to the DNS domain name, server, gateway

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and IP address.

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So there's other kinds of add ons that can be managed through a network manager.

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You can create multiple profiles.

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Even so, you can easily switch between different networks.

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As far as wireless networks go, they are automatically tied to their service set identifier or SS ID.

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And if you're working with a virtual machine or virtual box, it may not recognize your system onboard

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wireless network interface card.

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It must be aware of that.

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You may have to use an external network adapter, which we may reference in another video.

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The network manager provides integration with many types of VPNs like SSA, Open VPN, Cisco's VPN as

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well.

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Now let's look at some of the different things you can do with checking to see what your local network

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IP is.

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If you go back, we go back into our virtual environment, our colleague Linux distro.

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Then we open up a terminal.

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We can go ahead and use the command line from here.

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And notice we're at the county at caller interface and there's a dollar sign because it's a regular

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user account, not as a route.

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So we can do I have config.

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And notice that it's in this particular desktop environment.

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It's not there by default, depending on which desktop you install.

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You may have to change your setup to get all the same commands.

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So in our case, it's not that it was not there.

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It's not as we have the pseudo due route.

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An exit back out to a regular use urban use cleared a clearance rate with Cally.

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We're going to pseudo as you and we've already typed in the password so we got a different prompter

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notice.

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We have the town signs and now we are as root and I have config command works as per usual.

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And here we can see some different things like our local IP version for address.

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As well as our IP address, we can see different how many received and transmitted packets in frames

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that were sent.

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There's also this l0 this is the loopback address.

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This is essentially the same thing as pinging your network card.

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This is the in windows.

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This would be called the local host or the local loopback.

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Notice you can also check your local Mac address with I have config and there are basically three different

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ways to configure networking in Linux.

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You can use the graphical interface, you can use the interface up or down commands.

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And the system commands.

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So first of all, look at the graphical interface.

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Switch back over to Kelly.

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We can click on this button here and we can click Disconnect and we can see now we're disconnected from

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the network and we have a wired connection.

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And we'll go ahead and reconnect.

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And one of the things that you can do if you've typed a command before, you can press the up arrow

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and you will get back the last typed command.

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And in this case, I have config.

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And we've got our IP address, our network mask, and our broadcast broadcast is essentially the address

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you would communicate to on this network if you wanted to send traffic to everyone.

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If we want to go ahead and go into the interface file.

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We can go into the.

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The ETSI network interfaces file.

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So this is essentially all the interfaces that the system knows about initially.

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So it has the.

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Pulls the information from the interfaces data file.

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If we wanted to add additional interfaces to start at any time, we could do that.

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And you can also do it from the command line as well.

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And these are this is actually the main page or the manual page for the interfaces command.

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So if you wanted to set up different network interfaces with DHP versus Automatic, you could set up

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static IP addresses.

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If you see a pound sign and this file, essentially that means that it's an end of line.

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Comments.

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Or I should say it's just a comment and the one comments are not supported.

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So the comment has to be on its own line.

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And so it gives you some more amplified information if you want to learn in more detail what your different

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options are.

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And there are some also some different scripts that are in this folder as well, which are beyond the

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scope of this course.

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You could change things like the empty use size or the maximum transmission unit, how much data you

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want to pass over each packet.

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You can change the time to live.

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You can change lots of different things.

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You can set up tunnels with this command structure.

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This is the System D file, which is essentially the service and service manager for Linux.

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So whenever a it runs as the first process en route, so it essentially brings up all the other services.

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Anything else from other users get started separately?

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It's not normally invoked directly by the user, but it is started at boot time.

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You probably more likely interact with these the services that are managed by system this.

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System B also has some limitations as far as a lack of integrated support for wireless networks.

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So you may have to rely on other configurations for wireless support.

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Now let's talk about managing users and groups.

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So though Kelly is most often run while authenticated as a root user, you may often need to create

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non-covered accounts for various reasons.

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Especially if you're using Callie as a primary operating system.

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Additionally, the newer versions of calling have removed the root account and they've added any user

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accounts you can't sudo to root.

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That account is kiwi for the username and kiwi for the password.

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So Kelly Linux stores the list of users in the Etsy password file.

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That's Swg, which is a list of users.

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It stores the encrypted password of those users and the Etsy shadow file.

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So let's go ahead and take a look at what that means.

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We're going to use the cat command.

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And there is the Cali user and its corresponding hash password that is the other accounts might be system

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accounts or for certain services that do not have passwords.

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If we want to be able to add an account, we have to use the ADD user command.

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So the ad user command takes a pretty straightforward list of command.

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So let's go ahead and add a user briefly.

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Once they add user user one, and then it's going to add the group and it's going to add that user one

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into that user one group.

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It's also going to create a home directory and copy some files over to the Etsy scale directory.

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Now let's go ahead and give it a password.

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Her strong passwords will be for another another day.

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You can type in some other information here.

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Like their name, room number.

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You can put their work phone in.

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But their home plan.

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And then any other information.

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You want them to have, you know, say yes to confirm the information is correct.

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And now let's go ahead and clear the strangest.

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So we clean up our workspace here.

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Let's go and cat out the Etsy password file, which shows the list of users.

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Notice we have our newly created user account here.

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If user one John, his name is phone number and there's this shell and we still have the caller ID account

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which comes with our built in cally links.

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Let's go ahead and cashed out of the Etsy shadow file again and we'll see that we now have the user

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one account and its hash password.

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Now, for those that have not taken cybersecurity course for hashed, passwords are essentially how

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passwords are stored.

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It's just taking the plaintext of what I'm typing in when I'm creating the user account and I'm running

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it through a mathematical function, a one way function.

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The idea is that it's hard to undo this hash version of the password.

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It's not easily digestible or easy to break.

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The what they call the ciphertext version.

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So this is essentially just a scrambled version of the plaintext, and it's been run through something

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like MD5 or SHA wan, which we maybe shot.

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We learned about SHA256 when we were doing file integrity.

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Depending on the security of the system, it may hash the password more securely.

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So a longer hash is the more number of bits that you output, the more secure it is.

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So essentially a hash password is no matter what you put in as the plaintext, it's depending on the

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algorithm.

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It's always going to have the same amount of hash value, same amount of characters.

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It's so.

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We have, we talked about the wizard to be able to add users.

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We looked at the hash passwords and it's fairly straightforward.

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And let's.

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Also look at the Etsy group folder.

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And go and clear the screen.

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And then it's these are all the different groups that are some of these come by default.

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There's the Carlyle Group.

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There's the user group that was created when I created the account.

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You can actually add groups manually yourself as well.

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Let's go ahead and look at the.

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The Group Shadow file, which is essentially the.

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Password for any of the groups.

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We don't have any because you see this exclamation point, that means there's no password set for that

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particular group.

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So if you wanted to set a password, you could do that.

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So now let's look at managing different users and groups so we can modify existing accounts with several

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different commands.

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If you're logged in as a regular user, you can change your password, which will in turn update the

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Etsy shadow file.

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So let's go ahead and look at this real quick.

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Let's look at the shadow file from the perspective of our user one accounts and notice that the hash

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ends in a1ab you want.

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So let's, let's keep track of that VI.

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And what we're going to do is we're going to go ahead and password.

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We're going to change the password.

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That user to something else.

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And when we do that, it should also change.

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That hashtag, you know, we got the prompter.

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The password was updated successfully.

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Let's go ahead and cat out the shadow file of the new password.

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And then as we got a different value this time.

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So you're always going to in the case of the.

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You want to make sure that your password is long enough so that it is not easily accessible, but also

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that it's long enough that there's less chance of there being another user that uses the same password.

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Sometimes users may use the same password, and that's just going to happen because the natural order

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of things.

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So that's how an individual user changes their password.

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What if you want to change the full name of something, for example, or the finger information?

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So there's the finger command, which is the data that's stored in the ETSI password file.

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So.

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If we wanted to.

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Finger a particular user.

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And it would return back that user's information.

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Only the root can run this CHF and command or change full name or real username and information.

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So this could be the full name, the office number, the route, the phone number, all the stuff that

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we put in with the default account or when we created the account and.

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Essentially the default configuration is to keep users from changing their name.

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Of course, Root can do it.

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And there's different flags with CHF.

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And so if you wanted to change.

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The full name.

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You could change the room number.

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Maybe you just want to change the work number.

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And of course, there's always if you forget how to use a command, there's.

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Usually you can type dash help.

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Now some commands won't have the dash help.

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In this case, we have the dash.

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Oh, it's a little bit of a shorter abbreviation of the command van.

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Using the main page or the manual page.

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So let's go ahead and change the name of either one.

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Now let's say let's maybe we want to change the the room.

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Now let's go ahead and look at the change age command or the C h age command, depending on how you

237
00:21:18,570 --> 00:21:19,260
want to pronounce it.

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00:21:20,190 --> 00:21:20,790
So.

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00:21:22,740 --> 00:21:27,960
The Change Age Command allows the administrator to change the password expiration settings, bypassing

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00:21:27,960 --> 00:21:29,220
the username as an argument.

241
00:21:35,680 --> 00:21:37,180
So we'll look at the main page.

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00:21:44,050 --> 00:21:46,060
So you give it the options and the long end.

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00:21:46,060 --> 00:21:49,060
You can actually say what the last day.

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00:21:51,640 --> 00:21:54,610
More of their password was changed.

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00:21:55,030 --> 00:21:56,680
You could set an expiration date.

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00:21:58,630 --> 00:22:02,200
You can set a certain number of days before it's locked.

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00:22:06,730 --> 00:22:08,770
So there's the information on user one.

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00:22:09,580 --> 00:22:10,730
It doesn't expire.

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00:22:10,750 --> 00:22:11,770
It's inactive.

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00:22:12,220 --> 00:22:12,840
Never.

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00:22:13,240 --> 00:22:15,850
And the maximum and minimum number of days.

252
00:22:21,440 --> 00:22:26,450
So if you wanted to change the age of the password, you could set a minimum password.

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00:22:26,450 --> 00:22:26,840
Age.

254
00:22:32,810 --> 00:22:35,960
And we could set a maximum pass range we could set it to.

255
00:22:41,670 --> 00:22:49,110
The last password change and we have password expiration warning, we'll leave it the defaults and when

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00:22:49,110 --> 00:22:56,520
it goes inactive and we can just view the information now and see that all of our changes were just

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00:22:56,520 --> 00:22:56,850
made.

258
00:22:57,780 --> 00:22:59,580
So you can do that with any accounts.

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00:23:01,780 --> 00:23:02,680
You can also.

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00:23:04,180 --> 00:23:07,660
Require a users account to expire, for example.

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00:23:08,140 --> 00:23:13,630
So the system administrator, you might have to enforce password changing policies for a period of time.

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00:23:16,340 --> 00:23:19,550
So no other unauthorized users can view this information.

263
00:23:20,150 --> 00:23:22,880
Only the root user or somebody that can sudo to root.

264
00:23:23,570 --> 00:23:26,420
So let's go ahead and do a password

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00:23:29,420 --> 00:23:36,440
dashi and then we'll put in the user account user one and we've just now set that account to expire.

266
00:23:36,920 --> 00:23:43,340
So when that user tries to log in the next time, they should have to enter a new password.

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00:23:45,100 --> 00:23:48,700
Those are useful tools for managing individual user accounts.

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00:23:53,830 --> 00:23:56,230
Now let's look at managing users and groups.

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00:23:56,230 --> 00:24:01,510
So maybe you might want to disable or enable a user's accounts.

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00:24:01,900 --> 00:24:07,780
From a system administrator perspective, you might want to lock an account for somebody that's temporarily

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00:24:07,780 --> 00:24:13,090
leaving or maybe somebody is moving to a new project and they don't need that particular account anymore.

272
00:24:17,200 --> 00:24:20,770
Because you don't want them to build a modified delete or add files.

273
00:24:21,460 --> 00:24:27,130
There's also so the dash you flag under the password command allows you to unlock.

274
00:24:27,490 --> 00:24:31,480
So you lock it with the dash l command and unlock it with the dash you use.

275
00:24:31,510 --> 00:24:33,100
Let's go back to our virtual environment.

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00:24:34,000 --> 00:24:35,560
Let's go ahead and password.

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00:24:35,680 --> 00:24:38,200
Dash l user one.

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00:24:39,370 --> 00:24:41,020
And we've now walked out of.

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00:24:42,130 --> 00:24:43,540
Let's do password.

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00:24:44,950 --> 00:24:47,170
You use your alarm.

281
00:24:48,670 --> 00:24:49,420
And so.

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00:24:55,020 --> 00:24:55,830
From time to time.

283
00:24:55,830 --> 00:25:02,250
Let's go ahead and add another user account just because we can add user to

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00:25:05,700 --> 00:25:06,540
password here.

285
00:25:14,140 --> 00:25:15,400
Give it some information

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00:25:23,470 --> 00:25:24,200
and that's it.

287
00:25:24,220 --> 00:25:25,660
Yes, the information is correct.

288
00:25:26,080 --> 00:25:26,710
So let's go ahead.

289
00:25:26,710 --> 00:25:29,800
And do you want to lock that nucleus created?

290
00:25:35,530 --> 00:25:36,370
And there we go.

291
00:25:41,770 --> 00:25:43,690
So that user tries to log in.

292
00:25:47,530 --> 00:25:53,050
So we can still switch on the active session, but that won't take effect until the next time that they

293
00:25:53,050 --> 00:25:53,530
log in.

294
00:25:55,900 --> 00:25:59,080
So these are important things to know when you're managing users.

295
00:25:59,320 --> 00:26:00,640
Now, what about groups?

296
00:26:00,730 --> 00:26:05,620
Let's talk about managing groups so each user could be a member of many different groups.

297
00:26:05,620 --> 00:26:10,480
You might have a group for one particular department or another.

298
00:26:11,840 --> 00:26:21,650
And you have the need to switch around users amongst different departments as necessary so you can change

299
00:26:22,010 --> 00:26:22,490
the.

300
00:26:24,010 --> 00:26:29,080
User ID command or the user ID variable and also the group ID variable.

301
00:26:29,720 --> 00:26:33,220
Let's go ahead and look at a user and see what the ID command does for us.

302
00:26:33,820 --> 00:26:37,060
So we have, first of all, look at the main page.

303
00:26:37,430 --> 00:26:41,040
So this will print out the real and effective user and group IDs.

304
00:26:41,770 --> 00:26:45,370
So let's do ID user one.

305
00:26:45,370 --> 00:26:50,590
We can see that it's 1001 as the user ID or UID variable.

306
00:26:50,590 --> 00:26:52,780
It's 1001 for the group ID.

307
00:26:54,800 --> 00:26:56,390
And the groups that it's a member of.

308
00:27:03,690 --> 00:27:07,440
Now, let's say maybe we want to add a group.

309
00:27:10,630 --> 00:27:11,290
To the system.

310
00:27:11,290 --> 00:27:12,640
So let's use the ad group.

311
00:27:16,230 --> 00:27:17,810
First of all, look at the man page

312
00:27:22,910 --> 00:27:29,630
on some like Cicero's group, ad or ad group in this case, ad group or ad user.

313
00:27:29,660 --> 00:27:31,250
They're all part of the same command family.

314
00:27:31,580 --> 00:27:32,090
So we can.

315
00:27:33,380 --> 00:27:37,880
Modify these commands inside of the add user dot config final.

316
00:27:38,600 --> 00:27:45,110
But essentially if you don't give it any other options, it'll just set up each user group as a default.

317
00:27:45,530 --> 00:27:46,700
So let's go ahead and do

318
00:27:50,750 --> 00:27:50,900
so.

319
00:27:50,900 --> 00:27:54,080
We've added a new user group and notice it created a new group ID

320
00:27:57,590 --> 00:27:58,850
and we can use the.

321
00:28:03,230 --> 00:28:07,160
So let's say maybe we want to delete that group.

322
00:28:11,630 --> 00:28:17,420
So we use the little group user group command, and now that group is gone.

323
00:28:23,760 --> 00:28:29,370
So this is we can also look at if you put the ID command and don't put any parameters after it.

324
00:28:29,580 --> 00:28:33,450
In addition, return the ID for the user that it's actually logged in as.

325
00:28:35,400 --> 00:28:38,490
So notice that now user one is required to change the password.

326
00:28:39,540 --> 00:28:41,190
So we're going to change it to

327
00:28:44,010 --> 00:28:44,850
something else.

328
00:28:51,220 --> 00:28:56,290
First we have to enter our most current password and then we're going to change it to a new one.

329
00:29:00,790 --> 00:29:06,370
So it must use a longer password to note that it does require password complexity requirements.

330
00:29:08,220 --> 00:29:09,100
So we're going to do

331
00:29:17,620 --> 00:29:19,270
notes that accepted the password.

332
00:29:22,070 --> 00:29:26,980
We can cat out the ETSI password, e-verify or I'm sorry, the etsi shadow.

333
00:29:27,760 --> 00:29:29,140
There's the etsi password file.

334
00:29:29,150 --> 00:29:33,130
You can see the new user that was created.

335
00:29:35,790 --> 00:29:38,050
Let's go in cat off the shadow file.

336
00:29:38,350 --> 00:29:40,270
Notice we can't cat it out because we're not.

337
00:29:40,300 --> 00:29:42,700
Root So we're going to have this pseudo.

338
00:29:43,860 --> 00:29:44,430
The root,

339
00:29:48,400 --> 00:29:51,180
and that is that user one is not in that file.

340
00:29:51,180 --> 00:29:52,950
So we'll come to that back to that in a minute.

341
00:29:53,550 --> 00:29:55,320
Let's go and switch back over to Root.

342
00:30:06,670 --> 00:30:13,460
But we have to do it with the Callaway command or the Callaway user because that users in the zero file

343
00:30:14,400 --> 00:30:14,850
so.

344
00:30:16,350 --> 00:30:17,560
So we can add groups.

345
00:30:17,580 --> 00:30:20,610
Let's go ahead and add another group.

346
00:30:26,570 --> 00:30:29,990
Well, call this group, H.R..

347
00:30:33,050 --> 00:30:38,950
Well, I had a group for sales and maybe we'll use those in a future lecture.

348
00:30:38,950 --> 00:30:44,380
So add a group and delete group if we want to modify the group once we've created it.

349
00:30:44,380 --> 00:30:55,990
That's the group mod command so we can modify the group I.D. We can modify the name, we can change

350
00:30:55,990 --> 00:30:56,890
the password.

351
00:30:59,760 --> 00:31:01,410
And different other things.

352
00:31:01,420 --> 00:31:05,490
So the group information as we know is in the AC DC shadow file.

353
00:31:16,350 --> 00:31:19,380
So we didn't give it any chance to actually make the change.

354
00:31:19,890 --> 00:31:28,650
If you do group mod, if you mistyped the command or you type it in the wrong case, you won't get the

355
00:31:28,650 --> 00:31:32,370
actual any response back.

356
00:31:32,880 --> 00:31:34,710
So let's go ahead and change the name.

357
00:31:50,690 --> 00:31:53,300
Oh, add that syntax backwards.

358
00:31:54,620 --> 00:31:59,240
So when you're changing the name of your modifying, you have to put the what you want to change it

359
00:31:59,240 --> 00:32:00,980
to first, then the actual group

360
00:32:04,400 --> 00:32:05,150
and now.

361
00:32:10,320 --> 00:32:11,420
We should be able to.

362
00:32:14,350 --> 00:32:21,250
Return that information and we'll see the actual ruthlessness there.

363
00:32:32,660 --> 00:32:38,450
So if we want to do a add a user to a particular group, we can do that.

364
00:32:39,230 --> 00:32:42,740
We just have to use a different command called the User Mod Command.

365
00:32:43,190 --> 00:32:46,340
So let's go ahead and add a user to a particular group.

366
00:32:49,390 --> 00:32:55,120
And the to the screen, there's the user mod command.

367
00:32:55,120 --> 00:32:57,430
So it tells us we can modify the user account.

368
00:32:57,880 --> 00:33:03,880
So if we want to append that user to a group, we use that with the dash g option for the group name.

369
00:33:04,900 --> 00:33:05,650
You can.

370
00:33:07,360 --> 00:33:08,470
Change the comments.

371
00:33:08,770 --> 00:33:15,250
You can do different things with the user account, make it interactive, you can change the password,

372
00:33:15,940 --> 00:33:17,270
you could change the user shell.

373
00:33:17,290 --> 00:33:20,710
There's a lot of things you can do with this command, but right now we're going to focus just on the

374
00:33:20,710 --> 00:33:21,040
group.

375
00:33:21,550 --> 00:33:26,440
We're going to do user mod, dash a, dash g, and we're going to put in.

376
00:33:28,040 --> 00:33:29,900
The actual group that we want to change do.

377
00:33:36,790 --> 00:33:44,170
Which is going to be the user group and we're going to add user one to that user group.

378
00:33:45,880 --> 00:33:47,620
And so we don't have that user.

379
00:33:47,650 --> 00:33:47,980
All right.

380
00:33:47,980 --> 00:33:50,530
We changed the we changed the name, didn't we?

381
00:33:51,190 --> 00:33:53,250
So we got to make it new user group.

382
00:33:54,550 --> 00:33:59,680
And now that user account has been added to that group.

383
00:34:03,110 --> 00:34:07,730
So let's add the other user account we created to a different group.

384
00:34:08,090 --> 00:34:13,280
User might dash a dash g or add the user to to the group.

385
00:34:14,740 --> 00:34:15,610
And there we go.

386
00:34:19,010 --> 00:34:25,370
And with the group's demand, we can see what users are and which groups.

387
00:34:26,090 --> 00:34:33,230
So let's go ahead and do groups and with the user one and we'll see that user one is part of new user

388
00:34:33,230 --> 00:34:33,620
group.

389
00:34:34,160 --> 00:34:39,920
We'll do the group's demand for user two and we'll see that they're part of the group.

390
00:34:40,340 --> 00:34:43,910
So our commanders are accessible and that's what we wanted to happen.

391
00:34:44,600 --> 00:34:50,170
Now let's talk about configuring services inside of our Kellie Linux distributions.

392
00:34:50,180 --> 00:34:55,280
That's important because at some point we may want to look at different services that are running.

393
00:34:56,480 --> 00:35:03,950
If we do the Command D package with a uppercase L and a package name, it will list us all the files

394
00:35:03,950 --> 00:35:05,900
that are included in that particular package.

395
00:35:06,710 --> 00:35:14,840
So make sure the screen you package dash l just one dash, not multiple.

396
00:35:16,370 --> 00:35:21,950
And because Linux is case sensitive, I want to make sure that we're following the convention and there's

397
00:35:21,950 --> 00:35:25,490
all the different packages that are part of the TCP command.

398
00:35:26,150 --> 00:35:29,180
Let's say maybe I wanted to find out what all the packages are.

399
00:35:29,600 --> 00:35:31,730
As part of Wireshark, I can do that.

400
00:35:32,840 --> 00:35:34,730
So that's the Dash l command.

401
00:35:35,570 --> 00:35:38,240
See if I can zoom in a little bit to make this.

402
00:35:39,920 --> 00:35:42,500
A bit bigger for you guys.

403
00:35:48,280 --> 00:35:54,730
So we have the D package dash s command, which will show us any metadata that also comes with that

404
00:35:54,730 --> 00:35:57,100
package or any requirements.

405
00:35:57,190 --> 00:36:05,470
So for example, if the installs Okay or 30 things that it might need to be able to function.

406
00:36:06,220 --> 00:36:11,440
And that tells you a little bit about the package itself and what the package actually does.

407
00:36:12,040 --> 00:36:14,020
Let's go and look at the main page.

408
00:36:15,520 --> 00:36:20,340
Z packages an important program to understand.

409
00:36:20,350 --> 00:36:24,550
It is a package manager for Debian or debian based Linux.

410
00:36:25,750 --> 00:36:26,970
Obviously if you want to.

411
00:36:29,230 --> 00:36:30,520
Be able to understand.

412
00:36:33,170 --> 00:36:35,480
The descriptions are not going to be useful.

413
00:36:35,480 --> 00:36:38,300
So I always consult the software developers.

414
00:36:39,730 --> 00:36:46,050
Documentation, but you have the main pages and you also have the RD package command.

415
00:36:46,590 --> 00:36:52,530
So you can see if there are any packages that have been held for installation.

416
00:36:52,890 --> 00:36:56,820
You can actually force commands to packages to install.

417
00:36:56,820 --> 00:37:00,990
You can remove packages install even with DX package.

418
00:37:04,600 --> 00:37:06,070
And many, many other things.

419
00:37:12,810 --> 00:37:14,340
So let's talk about services.

420
00:37:14,640 --> 00:37:16,770
So we want to be able to work with services.

421
00:37:17,880 --> 00:37:23,160
That's changed a little bit in Lennox of some of the newer versions, but it's important to understand

422
00:37:23,160 --> 00:37:24,810
both ways to.

423
00:37:25,820 --> 00:37:26,960
How to run services.

424
00:37:27,080 --> 00:37:33,950
Services run as from configuration files in the case of as a sage or secure shell.

425
00:37:34,430 --> 00:37:39,710
Sage allows you to remotely log in to a machine transfer files and run commands.

426
00:37:40,040 --> 00:37:44,180
So the tool is sage or sometimes called open access.

427
00:37:44,180 --> 00:37:52,040
H, but it runs a service called the SS H Damon and open SS age is installed by default, but the SS

428
00:37:52,040 --> 00:37:53,450
H service is disabled.

429
00:37:54,020 --> 00:37:58,280
So let's go ahead and get that service started.

430
00:37:58,700 --> 00:38:02,840
We're going to use the system ctrl command start ss h.

431
00:38:04,580 --> 00:38:08,930
And we should system CTL status.

432
00:38:10,700 --> 00:38:17,390
SSA should see that in fact, running services server is running by vendor.

433
00:38:17,390 --> 00:38:18,890
It's supposed to be disabled.

434
00:38:20,650 --> 00:38:28,690
We can also set it if we want it to run en route by using the system ctrl command enable as h.

435
00:38:29,440 --> 00:38:32,920
So notice it's going to write that information or that script.

436
00:38:33,400 --> 00:38:34,120
So when.

437
00:38:35,940 --> 00:38:41,550
Kelly Lennox, boots up, sage will automatically be available, which is particularly useful, especially

438
00:38:41,550 --> 00:38:47,730
if you're going to be moving in and out of command shells and doing other things with your Linux distribution

439
00:38:49,080 --> 00:38:51,120
to clear the screen.

440
00:39:00,480 --> 00:39:08,220
So these same results can be gotten by using the service as a sage status command or essentially service,

441
00:39:09,240 --> 00:39:14,650
and then the name of the service and then status.

442
00:39:14,670 --> 00:39:16,920
So any command can be pretty much gone.

443
00:39:17,040 --> 00:39:23,280
You can also do service status all in older distributions.

444
00:39:28,410 --> 00:39:32,310
So in some cases, some versions of Linux will have different commands.

445
00:39:32,640 --> 00:39:39,060
So if you type the service, the staff status, all, it'll return all the services.

446
00:39:40,800 --> 00:39:42,600
It are running and it has a plus sign.

447
00:39:42,930 --> 00:39:44,760
I mean, it's actually running.

448
00:39:45,870 --> 00:39:48,710
So in here there's a plus sign next to SSA.

449
00:39:48,730 --> 00:39:52,560
So it's currently running, but any one of these other services can be called.

450
00:39:54,070 --> 00:39:55,690
So we will come back to this command.

451
00:39:56,020 --> 00:40:01,630
But I definitely want you to understand how to stop and start services, because from a security perspective,

452
00:40:01,630 --> 00:40:07,240
services can help you or they can also give you a way if you're doing a particular type of.

453
00:40:08,470 --> 00:40:09,080
Pen test.

454
00:40:11,080 --> 00:40:14,200
So as the stage runs the stage.

455
00:40:14,230 --> 00:40:18,160
Damon And then we can configure different things.

456
00:40:18,340 --> 00:40:29,020
Many servers will have SSD keys stored in the tell the slash dot SSA directory stage listens by default

457
00:40:29,020 --> 00:40:29,920
on port 22.

458
00:40:29,920 --> 00:40:32,140
But we can we can change that.

459
00:40:34,860 --> 00:40:42,120
But if you change the Sage Zaman egg file, you have to reload the service or restart the service.

460
00:40:42,900 --> 00:40:44,550
So let's go ahead and clear the screen.

461
00:40:45,670 --> 00:40:46,570
And we're going to go ahead.

462
00:40:46,570 --> 00:40:51,640
And what we're going to do is we're going to go ahead and generate some SSD guys with the SSD Key Gen

463
00:40:52,420 --> 00:40:53,050
Command.

464
00:40:54,340 --> 00:40:55,390
And what that will do.

465
00:40:55,390 --> 00:40:57,370
We can actually specify parameters.

466
00:40:58,030 --> 00:41:03,370
We don't have to, but it just makes it a little more complicated.

467
00:41:03,880 --> 00:41:06,280
But there's no there's no requirement to do so.

468
00:41:09,090 --> 00:41:16,830
If we press enter, it's going to generate a public private RSA key player RSA as the encryption algorithm

469
00:41:17,670 --> 00:41:20,880
named after the people who created it, Shamir and Adelman.

470
00:41:21,240 --> 00:41:25,190
And it's going to ask you, what final do you want to see the key in?

471
00:41:25,200 --> 00:41:32,070
So it's going to give you the root Slashdot Sage directory and then the name of the key.

472
00:41:32,640 --> 00:41:36,270
So you can just leave it default, hit, enter and it created that directory.

473
00:41:36,780 --> 00:41:40,140
And if you want a passphrase to add some extra randomness, that's fine.

474
00:41:40,530 --> 00:41:42,000
If not, we're not going to worry about it.

475
00:41:42,000 --> 00:41:47,910
So notice it tells you where your ID is saved at your public key.

476
00:41:48,570 --> 00:41:55,020
And then it also does a SHA256 hash of that key and some random ASCII art that goes to it.

477
00:41:55,410 --> 00:41:59,280
But if we got out to the screen

478
00:42:01,860 --> 00:42:03,780
in the SS directory

479
00:42:07,740 --> 00:42:11,520
that put a tilde in there, there's our open SSL private key.

480
00:42:12,180 --> 00:42:14,370
So we actually just created that ourselves.

481
00:42:14,370 --> 00:42:18,630
This is not one we've obtained from a server, but it's very common.

482
00:42:18,630 --> 00:42:24,990
You might need to create an SS key to be able to log in securely to a virtual machine or to a web server

483
00:42:24,990 --> 00:42:26,040
or something like that.

484
00:42:28,340 --> 00:42:35,930
If we change to that directory next to the screen and we'll do the last command will notice, there's

485
00:42:35,930 --> 00:42:37,730
your public key and your private key.

486
00:42:38,090 --> 00:42:39,230
So the private key

487
00:42:43,010 --> 00:42:44,060
is much shorter.

488
00:42:44,690 --> 00:42:48,710
And it also gives the I'm sorry, the public key is much shorter.

489
00:42:48,710 --> 00:42:53,180
So when you log into a server, you might see other users public.

490
00:42:53,180 --> 00:42:55,970
He's in this particular folder.

491
00:42:56,480 --> 00:43:00,560
So this is very, very common and it's an important concept to understand.

492
00:43:04,560 --> 00:43:06,930
So let's go look at the SSA config file.

493
00:43:15,720 --> 00:43:21,120
So we're going to look in the Etsy Association directory so we can see the Essence HD on our store config

494
00:43:21,120 --> 00:43:21,480
file.

495
00:43:22,050 --> 00:43:28,650
And we're going to edit that with a text editor in this case, Vim.

496
00:43:32,360 --> 00:43:39,460
And we can see it's pointed to a particular path of where it wants to look.

497
00:43:39,540 --> 00:43:41,390
So this is the system wide file.

498
00:43:42,080 --> 00:43:46,580
In this case, we can notice everything that's in blue.

499
00:43:46,580 --> 00:43:48,050
These are all commented out.

500
00:43:48,300 --> 00:43:52,430
If there's no hash tag in front of it, that means that it's enabled.

501
00:43:52,880 --> 00:43:58,240
So you can make some changes here, such as the default port that you wanted to run on.

502
00:43:58,250 --> 00:44:03,200
So you can uncomment this line by pressing the answer key.

503
00:44:03,650 --> 00:44:05,420
And we could actually change the port.

504
00:44:06,920 --> 00:44:09,890
And notice the syntax also highlighted with it as well.

505
00:44:10,370 --> 00:44:14,600
So maybe you wanted to change it to a higher level port number, for example.

506
00:44:32,130 --> 00:44:35,800
So maybe we want it to be 49,102 or something like that.

507
00:44:36,310 --> 00:44:39,760
So we make our change, we hit the escape, we write it to the file.

508
00:44:40,300 --> 00:44:43,720
And then we're going to have to do we're going to have to change.

509
00:44:49,020 --> 00:44:50,640
We're going to have to reload the config.

510
00:44:58,410 --> 00:44:58,740
But

511
00:45:02,460 --> 00:45:03,150
and there we go.

512
00:45:03,210 --> 00:45:07,440
See, it's active and it's running and it will be talking on.

513
00:45:09,840 --> 00:45:10,920
A different port.

514
00:45:13,590 --> 00:45:15,000
So let's go ahead and exit out.

515
00:45:16,320 --> 00:45:19,050
Now we're going to talk about some of the.

516
00:45:21,400 --> 00:45:23,470
Databases that you might see on telly.

517
00:45:23,470 --> 00:45:28,450
One x PostgreSQL is a database server, it's relational database.

518
00:45:28,450 --> 00:45:34,790
Some services will access the database over the network and might need authentication from the database.

519
00:45:34,800 --> 00:45:43,720
So if we want to start the database, we'll have to go into our command line and we can query that service

520
00:45:44,440 --> 00:45:45,190
just like we can.

521
00:45:45,190 --> 00:45:45,820
Anything else?

522
00:45:45,820 --> 00:45:47,770
I'm going to change back to the home directory.

523
00:45:52,110 --> 00:45:57,420
And we're going to use the service Oscar sequel status.

524
00:45:58,530 --> 00:46:01,140
We can see that it's loaded, but it's not currently running.

525
00:46:01,650 --> 00:46:04,490
You can do the same thing with the system Ctrl command.

526
00:46:07,290 --> 00:46:15,810
So if we want to start, we can start the Postscript Sequel Service and it'll take a moment and then

527
00:46:15,810 --> 00:46:18,720
that database will be open by default.

528
00:46:19,260 --> 00:46:28,950
Postscript Sequel Lessons on TCP Port 5432 and on that particular socket in the VAR Ron Postscript sequel

529
00:46:28,950 --> 00:46:29,580
directory.

530
00:46:41,160 --> 00:46:44,160
Let's throw a change to the wrong directory.

531
00:46:47,640 --> 00:46:51,150
And there's the PostgreSQL directory

532
00:46:54,240 --> 00:46:56,080
and we can see some different things in here.

533
00:46:56,130 --> 00:47:03,990
Notice it has a lock on the file and it's calling because we don't want to have mistakes made or unauthorized

534
00:47:03,990 --> 00:47:04,680
changes made.

535
00:47:04,680 --> 00:47:10,800
So there is a in the AC directory as where most of the configuration is.

536
00:47:17,790 --> 00:47:19,900
So we can see in here in.

537
00:47:21,350 --> 00:47:21,690
Okay.

538
00:47:24,680 --> 00:47:26,180
This is version 12.

539
00:47:26,690 --> 00:47:30,800
And we can see here there's the different config files with Postgres.

540
00:47:30,800 --> 00:47:36,830
The Postgres sequel, not config file is kind of carried it out to the screen so you can see what it

541
00:47:36,830 --> 00:47:37,370
looks like.

542
00:47:37,970 --> 00:47:42,890
I may not have to mess with it too much unless you're doing some customized operations.

543
00:47:45,980 --> 00:47:53,270
But essentially the PGA underscore HPR dot config file will define who's allowed to connect and how

544
00:47:53,270 --> 00:47:54,170
they're authenticated.

545
00:47:57,330 --> 00:48:01,050
So you can set up if you want, customize extensions here.

546
00:48:08,010 --> 00:48:12,030
So if you want, this is kind of almost like your firewall, for example.

547
00:48:12,300 --> 00:48:14,130
Where do you want to allow connections?

548
00:48:14,570 --> 00:48:17,760
Of course you don't want to disable the rules.

549
00:48:18,630 --> 00:48:21,000
These are just the different networks from which.

550
00:48:23,760 --> 00:48:28,140
If you want to allow connections that are non-local, you have to add more hosted records.

551
00:48:38,660 --> 00:48:41,870
So let's talk about some more configuring the services.

552
00:48:41,870 --> 00:48:47,930
So services like Metasploit and others require the PostgreSQL service.

553
00:48:49,610 --> 00:48:50,060
And.

554
00:48:51,710 --> 00:48:56,870
PostgreSQL allows for multiple versions of the database to be installed and what they call clusters.

555
00:48:57,680 --> 00:49:02,810
You can actually create new users with respect to PostgreSQL.

556
00:49:07,120 --> 00:49:11,320
And new roles so we can switch over to the.

557
00:49:14,230 --> 00:49:15,610
Postscript User account.

558
00:49:18,710 --> 00:49:27,970
And we're going to say we want to go ahead and create user mindset for Metasploit framework, be that

559
00:49:27,980 --> 00:49:32,570
apps that are ready, that's going to ask for a new password.

560
00:49:37,740 --> 00:49:38,720
And there we go.

561
00:49:38,730 --> 00:49:40,560
So we've created a new user account.

562
00:49:43,850 --> 00:49:45,640
Notice I didn't type exit properly.

563
00:49:45,650 --> 00:49:49,160
I type it in all caps, so it did not work correctly.

564
00:49:49,160 --> 00:49:51,470
So if you wanted to drop that user.

565
00:49:54,700 --> 00:49:55,390
You could do that.

566
00:49:55,420 --> 00:49:56,320
There's also the.

567
00:50:02,560 --> 00:50:05,260
So we need to remove our PostgreSQL account.

568
00:50:07,140 --> 00:50:15,270
Of course, only super users and users that have the appropriate role in remove PostgreSQL accounts.

569
00:50:15,570 --> 00:50:17,490
So of course you have to be able to sudo to root.

570
00:50:18,510 --> 00:50:22,260
You can also use you can create databases.

571
00:50:26,280 --> 00:50:29,330
Let's go ahead and do that.

572
00:50:30,240 --> 00:50:34,980
So if you want to create a new Postgres database, you'd give it a connection option.

573
00:50:35,640 --> 00:50:39,140
The normal way, if you're the one creating it, you'll be the owner.

574
00:50:39,150 --> 00:50:41,010
Unless you want to specify a different.

575
00:50:42,850 --> 00:50:48,550
Database type, you can put the location, the version number, many other things.

576
00:50:48,550 --> 00:50:51,430
There's usually some different options.

577
00:50:54,190 --> 00:50:56,830
So you could set it to be on a certain court number.

578
00:50:59,080 --> 00:51:02,170
In this case, we'll go ahead and create the database and just call it demo.

579
00:51:03,040 --> 00:51:06,790
And because we don't have route, that did not work.

580
00:51:08,710 --> 00:51:13,510
So you can see that the new versions of Kelly have locked it down somewhat, but just know that this

581
00:51:13,510 --> 00:51:16,120
is basically the same process that you're going to follow.

582
00:51:19,010 --> 00:51:25,280
So if you want to create a new super user account, you also have to create connect as a super user,

583
00:51:25,280 --> 00:51:26,990
not just for the create role privilege.

584
00:51:27,320 --> 00:51:32,690
So if you're a super user, that means you can bypass all the service permission checks within the database.

585
00:51:32,690 --> 00:51:35,210
So you want to keep your super user control.

586
00:51:36,710 --> 00:51:38,900
Close hold should not be granted lightly.

587
00:51:39,710 --> 00:51:41,960
You can also use the drop user command

588
00:51:44,630 --> 00:51:54,290
to remove an account and you could do the drop DB command to remove a database entirely.

589
00:52:00,940 --> 00:52:06,700
So there's no real difference between creating databases from the command line and doing it from the

590
00:52:07,240 --> 00:52:08,890
graphical utility.

591
00:52:09,370 --> 00:52:13,870
But at least now you've seen multiple ways of doing this process.

592
00:52:15,010 --> 00:52:15,550
So.

593
00:52:19,040 --> 00:52:22,820
And there are some important tools to manage these different clusters.

594
00:52:23,150 --> 00:52:25,790
There is post breast create cluster, job cluster.

595
00:52:26,540 --> 00:52:30,920
There are if you want to list out the different clusters that are there.

596
00:52:38,700 --> 00:52:42,210
So these things may change from.

597
00:52:43,510 --> 00:52:44,620
Version two version.

598
00:52:49,080 --> 00:52:49,360
Yes.

599
00:52:49,410 --> 00:52:50,640
I made a typo there.

600
00:52:50,940 --> 00:52:55,260
So there's only one cluster right now listening on 5432.

601
00:52:55,770 --> 00:53:00,810
If I want it to create a cluster, we can do that.

602
00:53:06,450 --> 00:53:08,060
It was call it new.

603
00:53:08,300 --> 00:53:09,860
So you have to give it some options.

604
00:53:09,860 --> 00:53:10,530
Who owns it?

605
00:53:10,590 --> 00:53:11,540
The by the.

606
00:53:12,880 --> 00:53:16,960
So that's beyond the scope of this course, getting in too much into the weeds.

607
00:53:16,960 --> 00:53:18,220
But we will.

608
00:53:19,420 --> 00:53:27,310
So it's important to understand the different types of databases, especially as a hacker or Linux tester,

609
00:53:27,310 --> 00:53:32,390
because you may have to probe certain databases and different databases.

610
00:53:32,410 --> 00:53:36,460
Between my sequel and Postgres, they'll have slightly different commands.

611
00:53:38,890 --> 00:53:40,660
Which we may cover in future lectures.

612
00:53:41,260 --> 00:53:45,120
So how do we configure the web server?

613
00:53:45,130 --> 00:53:49,330
So besides having a database, we might have to have a web frontend component.

614
00:53:49,990 --> 00:53:56,550
Generally, Apache is the most common web server that's on the Internet.

615
00:53:56,570 --> 00:54:00,400
Most of the web services, I think like 60% of all web servers run Apache.

616
00:54:00,880 --> 00:54:08,740
So Apache created the PDP server project as an effort to be able to maintain an open source server for

617
00:54:08,740 --> 00:54:10,180
modern operating systems.

618
00:54:12,690 --> 00:54:15,030
And essentially the idea was that it would be modular.

619
00:54:15,300 --> 00:54:21,150
It would be very easy to work with and add new functionality.

620
00:54:26,740 --> 00:54:27,720
Let's see.

621
00:54:28,920 --> 00:54:35,700
And the newer version, the Linux, it's named Apache two by the version is one version 2.4, I believe

622
00:54:35,700 --> 00:54:40,230
was the latest version if you wanted to find out more information.

623
00:54:43,160 --> 00:54:44,180
About Apache,

624
00:54:47,330 --> 00:54:54,630
you can go to B, D as in it's named after the HDP Daemon.

625
00:54:55,310 --> 00:55:02,330
You could go to that particular resource and they will show you information about the latest and greatest

626
00:55:02,330 --> 00:55:04,610
versions, all the different modules.

627
00:55:04,910 --> 00:55:10,010
And you can see it's been the most popular server since the nineties and this year it celebrates its

628
00:55:10,010 --> 00:55:11,690
25th anniversary.

629
00:55:11,690 --> 00:55:16,910
So it's a, well, well-supported, well-documented web server, although from a security perspective

630
00:55:16,910 --> 00:55:21,860
that also makes it a big target because it's installed a lot of places.

631
00:55:22,340 --> 00:55:26,510
So let's go ahead and look at some things we can do with Apache.

632
00:55:36,340 --> 00:55:40,510
So we can see the same commands with the system, the versus the service commands.

633
00:55:40,840 --> 00:55:48,040
So let's go ahead and Service Apache two and let's go ahead and start it and we'll see that it'll take

634
00:55:48,040 --> 00:55:49,030
a moment and then.

635
00:55:50,230 --> 00:55:51,460
We can query it now.

636
00:55:51,470 --> 00:55:55,000
It's active and it's running and we can see that.

637
00:55:56,230 --> 00:56:03,820
If we go to a web browser inside of our Kali Linux distro, we will see a default web page.

638
00:56:05,850 --> 00:56:06,960
Let's go to our.

639
00:56:10,270 --> 00:56:15,610
Usual applications and we'll open up they have they've added in the newer versions they've added in

640
00:56:15,610 --> 00:56:17,980
chromium seven or Firefox.

641
00:56:18,430 --> 00:56:25,600
So we can have a web browser and we'll put in the local host IP address.

642
00:56:30,030 --> 00:56:35,130
Or the 120 7.0.0.1 address.

643
00:56:35,550 --> 00:56:38,310
And we'll see that we have the Apache default Web page.

644
00:56:38,940 --> 00:56:39,510
So this is.

645
00:56:39,690 --> 00:56:42,780
This shows the location of the Apache config file.

646
00:56:43,170 --> 00:56:45,810
Any ports that are open, what modules are enabled.

647
00:56:46,110 --> 00:56:49,020
So of course, you want to disable this from a security perspective.

648
00:56:49,620 --> 00:56:57,870
And most of the Apache website files will be located in the var slash w w directory.

649
00:57:00,020 --> 00:57:01,640
So let's go back to our slides here.

650
00:57:02,790 --> 00:57:03,230
So.

651
00:57:06,940 --> 00:57:13,380
Once we create Apache or once we enable Apache, it has different modules that we can use.

652
00:57:13,390 --> 00:57:15,220
We can enable mods with it.

653
00:57:15,220 --> 00:57:16,120
You can use the.

654
00:57:23,680 --> 00:57:25,930
You can use the A2 and Mod Command.

655
00:57:26,560 --> 00:57:31,660
So if you need to enable or disable an Apache module, you can do so.

656
00:57:32,590 --> 00:57:38,320
You can set it to quiet mode so it doesn't show informative methods or messages.

657
00:57:40,120 --> 00:57:43,240
There's other commands, like the Apache two controller.

658
00:57:44,530 --> 00:57:46,600
We're working with Apache Services.

659
00:57:52,060 --> 00:57:54,820
So this is the Apache server control interface.

660
00:57:54,820 --> 00:57:58,570
So it takes more simplified one word commands.

661
00:58:02,440 --> 00:58:09,790
So if you want to make quick changes to it or you want to start the Apache so you can do Apache two

662
00:58:09,790 --> 00:58:12,610
controller start.

663
00:58:16,710 --> 00:58:21,240
So it's going to invoke the system CTL command as well.

664
00:58:22,110 --> 00:58:23,100
So it's already running.

665
00:58:23,720 --> 00:58:25,680
So what if we change this to stop?

666
00:58:28,710 --> 00:58:34,110
So now we'll notice that the Apache server is no longer running.

667
00:58:36,720 --> 00:58:38,200
So let's go ahead and start it again.

668
00:58:39,390 --> 00:58:40,860
And we have our web server running.

669
00:58:43,610 --> 00:58:50,410
So on Apache and its config file, it can load what are known as virtual hosts.

670
00:58:50,420 --> 00:58:54,560
These are essentially extra identities for the web server.

671
00:58:54,560 --> 00:58:58,550
So you can have multiple hosts on a web server.

672
00:58:58,940 --> 00:59:07,670
The default virtual host is in the Apache two default config file and then every virtual host after

673
00:59:07,670 --> 00:59:10,940
that gets described by the site's available.

674
00:59:15,460 --> 00:59:23,500
So you can do a minimum virtual host for the website which is stored in the slash service slash every

675
00:59:23,540 --> 00:59:25,660
WW dot example dot com.

676
00:59:27,760 --> 00:59:31,210
Let's go ahead and look at the Apache config file.

677
00:59:45,200 --> 00:59:49,400
And there's the default Apache config, follow the default virtual host.

678
00:59:49,410 --> 00:59:53,480
So you can see that the document route is the route where all the websites go.

679
00:59:54,170 --> 00:59:55,460
You can see the server admin.

680
00:59:55,460 --> 00:59:59,000
This is the webmaster or the person that manages the website.

681
59:59.420 --> 1:00:01.580
So a lot of information can be obtained from this file.

682
1:00:01.580 --> 1:00:04.070
So you want to guard this file very carefully.

683
1:00:09.700 --> 1:00:14.100
So let's talk about some more things requiring authentication.

684
1:00:14.110 --> 1:00:21.160
So if you want to run additional directives outside of the normal Apache config file, one of the ways

685
1:00:21.160 --> 1:00:24.670
to do that is through something called an access file.

686
1:00:25.880 --> 1:00:30.200
This access file is essentially a distributed configuration file.

687
1:00:30.860 --> 1:00:36.950
So every time a request comes in, that HD access file will handle those requests.

688
1:00:36.950 --> 1:00:40.130
And this is done normally on a per directory basis.

689
1:00:40.820 --> 1:00:43.190
So you can rename access files.

690
1:00:45.080 --> 1:00:52.610
Something else using the access file name directive, and you could also allow one to be overridden

691
1:00:52.610 --> 1:00:53.300
or not.

692
1:00:54.380 --> 1:01:01.700
So in this case here, if you want to require authentication, you could require a valid user using

693
1:01:01.700 --> 1:01:05.570
the off named private directory and you could set the.

694
1:01:07.560 --> 1:01:14.730
Authentication user file app that etsi apache to all files slash hd password dash private.

695
1:01:17.810 --> 1:01:19.060
So some extra information.

696
1:01:19.070 --> 1:01:24.830
Typically, we've talked about the network manager, we've talked about command line tools.

697
1:01:25.280 --> 1:01:28.940
We've talked about different ways of managing users and group accounts.

698
1:01:29.840 --> 1:01:32.330
We've talked about adding users.

699
1:01:32.330 --> 1:01:33.820
We've talked about CCH.

700
1:01:34.310 --> 1:01:38.000
We looked at PostgreSQL as well as Apache.

701
1:01:39.540 --> 1:01:47.160
So in summary, we talked about configuring the network, the different ways with desktop command line

702
1:01:47.340 --> 1:01:48.080
using system.

703
1:01:48.930 --> 1:01:54.240
We looked at managing accounts, creating accounts, disabling accounts.

704
1:01:55.350 --> 1:02:01.350
We looked at different ways to configure services like Sage and the Apache game.

705
1:02:01.350 --> 1:02:09.810
And we we looked at PostgreSQL SQL Services, we looked at setting up Sage for remote log ins and how

706
1:02:09.810 --> 1:02:13.230
to generate sage keys for particular servers.

707
1:02:17.210 --> 1:02:25.190
And now you should be more familiar with working with daily Linux and particular services networks and

708
1:02:25.190 --> 1:02:26.150
user accounts.