408 lines
17 KiB
Plaintext
408 lines
17 KiB
Plaintext
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Episode: 497
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Title: HPR0497: Kris Findlay discusses Secure Socket Handler
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Source: https://hub.hackerpublicradio.org/ccdn.php?filename=/eps/hpr0497/hpr0497.mp3
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Transcribed: 2025-10-07 21:46:43
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---
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.
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.
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Welcome to my talk on SSH, give us a guide to secure socket
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Anders. My name is Chris Finley.
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I'm a webmaster for the Linux site and you can easily
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site. Help us to take communication with
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everybody in the community and hope it all goes well.
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.
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So what we're going to talk about today,
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hopefully I want to learn what SSH is.
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What some of the basic commands are, how easy it is
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going to be able to use it in both day-to-day life
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and possibly some of the jobs.
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The logic transfer files, most securely,
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in a manner that's going to help you do what you
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will need to do.
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And how to, the notes that Wi-Fi hotspots and
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plus of that aren't actually really secure.
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And SSH can help you to make that secure.
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So, say why do you want to know this?
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Say Wi-Fi hotspots. When you connect to Wi-Fi hotspot,
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you're connecting to everybody there,
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you can see where you're going, what sites you're going to
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stuff like that, by stuffing your connection and stuff like that.
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Whereas if you use SSH, you can connect to another
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machine through an encrypted tunnel and secure
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your connection that way.
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Make it less easier for people to see what you're doing.
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You know, you want people to steal in your bank account
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details or something.
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I mean, if you're transferring files like, for example,
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you can make.com, try sending files across the internet
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to other customer details and bank details and
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really, and plain text files.
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Anybody could just stop along, read the files,
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no problem with that.
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And it'll be quite hammered for that.
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Whereas the SSH, the whole connection will be
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encrypted and you wouldn't built it.
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See the values and stuff.
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But also, actually, to connect to your computer
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from anywhere remotely, you can get an internet connection,
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which can be very handy between files,
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control your computer, download your TV series,
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or everyone.
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So, let's say, start off with what SSH is,
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a little bit when ports were opened,
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what's used for, what it replaced,
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and some basic uses and commands.
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So, basically, what is SSH?
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It's a secure socket handler.
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It's not a protocol, so it's not one application.
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It's a set of applications.
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And it uses a cryptography, a public key per.
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So, you have to provide a public key
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and have the private key yourself,
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so that you can connect to servers and things,
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securely.
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It can be used to transfer files using an SEP,
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a secure copy.
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All that I say, all that's done to a secure socket,
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on usually port 22,
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which is different than your emails, like usually SMTPs,
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like port 25, HTTPs, like port 18, things like that.
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Although, it is recommended that you change that port
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in the configuration file to something less obscure.
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So, you won't win by when ports were open.
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SSH was initially developed in 1985,
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by a guy at Helsinki University.
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They were having problems with people still in passwords
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and breaking into their system and things like that.
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The tools they were using,
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just worked up to the grade,
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if they were going to try and secure these tools
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and make them most secure,
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they basically have to rewrite them all entirely.
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And that's just not helpful.
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It's not tight enough to take consumers and it costs a lot of money.
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So, this guy,
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Helsinki University,
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rewrote SSH using a lot of open source tools
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that were already available,
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released under the GNU and the GPL license.
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Later on, a few years beyond that,
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they started revising the code and moving on.
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But the guy started his own company,
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making improvements in stuff to SSH
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and made it proprietary.
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So, you couldn't get the code,
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you couldn't get the source code,
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you couldn't end with it.
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Of course, a lot of people were like,
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that's not good enough,
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we want an open source version,
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we don't have an open source code.
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So, they went back to the 98,
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3BSD went back and said,
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right, where's the original code that's open source?
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Because under the GNU license,
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which means they can't take it back and say,
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no, this is proprietary,
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they've got to have that code and it's got to be available.
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So, they took that code and proved on it,
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revised it a bit more,
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and released it as open SSH,
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which is now probably most commonly used,
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former of SSH.
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There are more other proprietary versions,
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versions for Microsoft Mac,
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which I think Mac uses open SSH as well.
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I think there's one SSH for Windows,
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I think.
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Yeah, how does SSH port as well?
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Is there a way to support as well?
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Is that under side G1?
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Yeah, it's on.
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All right, cool.
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And of course, that version was ported
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from 3BSD to different operating systems,
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like Linux,
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which is predominantly used in Linux,
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and Unix systems.
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And that's for low.
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Basically, there's a log in here,
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a system with SSH.
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It's coming down to the command line
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or you can use a GUI tool,
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or something like that,
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to do some applications.
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So, I'll just say we've probably
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what we've used for before on it.
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So, I mean, there's lots of different things
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you can use the SSH toolset
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and protocols for,
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including logging in the model list,
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as we talked about,
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which was placed in programs called,
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we used before, we're called townet,
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and our logon.
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But I'd say these didn't have the security required.
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But you can also,
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securely execute one command.
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So, you've got a program that's running on another machine,
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and you just want to restart that program
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or do it without actually doing anything else.
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You can just send that single command to restart it,
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and not bother by whether it's done or not,
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and leave it to it.
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SCP is quite a good one.
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Very good one.
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I mean, for copying files and directories around,
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you're copying it to a remote host,
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and then SCP connection.
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You've got to have more constant connection,
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because it's less likely to drop.
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It's encrypted.
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So, I'm always going to monitor what you're sending across these.
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That was actually said before.
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There is an alternative to that, which is S-F-D-P,
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which is a protocol that came out after that.
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It's still part of the S-S-H suite at all.
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But not of F-D-P servers support it.
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So, but it will fall back to using S-C-P if it's not supported.
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So, it's got the redundancy there as well.
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You can use it in combination with lots of other programs,
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like R-Sync is a program that synchronizes files to the systems.
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It checks the files match the dates, times the same files
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and copies them across.
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And you can say it's only copy files that have changed.
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So, it's great for backing stuff up.
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So, you can just use S-C-P connection, connect to the server,
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and transfer those files back to your backup files and systems up.
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One of the things that I tend to use a lot of most of myself
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is what we'll put forward in them, or tunneling.
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Basically, this is what we use to protect you from a Wi-Fi hotspot.
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You create a tunnel to your computer, or a computer you've got access to,
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on port 80 out to your internet.
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And then you can access any page or any website or anything that you can access
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from your home computer.
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Downloads those data to your computer, and then sends that data back to you through the tunnel.
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No one can monitor that tunnel, so they don't know what pages you're going to,
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they don't know what, you know, sister servers you're going to, and so on.
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For example, in the university, you try to go to one of the game sites,
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a game spot or something, and you try to get there, and the university says,
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no, that's a game site, you're not getting there, block.
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But if you tunnel out to your own machine, you can go to that page as much as you want.
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You don't even know you're there.
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And I think it's mainly one of the Unix systems and Linux systems,
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is the ability to forward X1M1 system, X1M1, which is your Windows system.
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So you can say, right, I want to run Firefox.
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But I like the version that I've got on my desktop on my bootmarks.
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I've not copied the bootmarks to my laptop.
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You can use the tunnel, SH to the machine you're in,
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the special option next forward.
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And to run Firefox, and it'll run it from your machine on your desktop,
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in your laptop you send it.
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So the whole application just loads up as if you were sitting in your desktop.
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It might be slightly slower, but it's there, it's got your bootmarks.
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And when you try to access files and stuff,
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it'll access files on your own server, not the files on your local system.
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Of course, you can use it with the software protocols and stuff,
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as a proxy, and forward all your web access and everything through that,
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through your tunnel and security connection.
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One of my favourite uses for it is the Pro SSHFS,
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which takes the remote file system on a remote computer.
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And it's a hard drive in your own machine.
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You just give it a location.
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This is where you want to mount it.
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This side, and it mounts it as if you were sitting there locally.
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You can copy stuff, copy stuff to it, modify files,
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and as if you were that machine there on your local system.
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And of course, it's still all encrypted.
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Of course, you can monitor systems with it as well,
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by logging into the system, running the monitor scripts.
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And that is that way.
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So as I said earlier on, we replaced some programs
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that was the whole point in the protocol.
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The things that are logging was usually used to log into remote systems
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that you'd access something like that.
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But it was just sending the plain text password across the network
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to log into the system, which isn't any use.
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Telling it is still used today.
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But mainly is it back up to something like SSH or SAP,
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or something like that.
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If something like a router or something like that,
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those goes down, and you can't get to the web page interface,
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you can usually tell it into it and use it that way.
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And you get a terminal just as you do with SSH or something like that.
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But it tends to be only using small doses these days.
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And Archer, so I haven't seen you in a long time,
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whether people still use it on Unix systems, I don't know.
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But it's very much the same as our long-term.
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I don't know if they're very much pretty the same thing.
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So let's say we're going to discuss some of the basic commands.
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Most of these are run from the command line.
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There are GUI apps that allow you to use these as well.
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The basic commands, SSH, a space, the IP address
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or the host name of the server you want to connect to.
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DashL, a new username, that on the system you're connecting to.
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If it's the same username, then you don't need to provide that.
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You can just try that.
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And that'll give you a basic shell window where you can
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own the other system and you can access it
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and don't think you can in that shell for that machine.
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You want to specify a port.
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So you've changed the port from 22, which was a default.
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It's just another dashp on the end of the line.
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And specify the port number that you've changed to.
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We talked about X forwarding.
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We've run the program from your own machine.
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And to do that, it's just to simply add in the dash cap at X
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to the front of the command.
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And that'll forward any application you've tried to run on the other system.
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We'll run any GUI application.
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We'll run on your system.
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And as if you were there.
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And of course, the single row command is just pretty much as easy as a default.
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It's the same command.
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You've got your SSH.
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You're in what IP, if you're in what address.
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You log in your username or your dashp report.
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And the command you want to run.
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And it'll just run that command and then come back to your own command line again.
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So this is another program within that suite of protocol.
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From within that protocol.
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SAP is a secure copy to copy your files across from one system to another
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through this encrypted connection.
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The main reason people tend to use it is to be honest,
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FTPs, clunky, it's a little slow, but like HDDP,
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it's not quite what you want to be doing.
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It can quite often, FTP quite often drops a lot.
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More SAP tends to seem a bit more stable.
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But it's just a very simple command again.
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The SAP space, the file you'll actually want to transfer.
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The more servers IP address.
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A colon with two dots above each other.
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And the directory or you want to place it in the file.
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And of course your dash or username or dashp for your ports or whatever.
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And so that'll just copy that file over the other system.
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And it'll be a result of times like that.
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And you can also perform it the other direction by swapping the two values around.
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So instead of collecting the remote server in the protocol location,
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you use the other way around.
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Oh, sorry?
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Yeah.
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Yeah, you just pull it instead of pushing it for the other way.
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All I said, these tools are majoring at the time a lot of people using the command line
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and just for quickness of ease.
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But there are graphical applications for that.
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For people that don't have, they don't really want to use the command line.
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One of those is GFDP.
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Swamp source.
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It's available everywhere.
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And it's just a great little program.
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It does have to be a lot of different protocols.
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One of the protocols that we'll do is SSH.
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And it just log in like you would in any other FTP program.
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But then you need to use your host name.
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You put in your IP address or your host for your connection you were going to make.
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You put in the port, your username and password.
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And click the drop-down box and change the SSH.
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And then click connect.
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And it'll come up as if you would do in any other FTP program.
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And list all your files.
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And you just cut me across.
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And you want quick, easy.
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And we'll do it.
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Let's say someone will have asked us about SSHFS and things.
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The commands are still pretty simple.
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You SSFS, your remote server,
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it's location,
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and location you want to store it at.
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And so you've got things up there.
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One, two, one, six.
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This is SSFS.
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One, two, you want to say one for storage.
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And it's mounted in my folder in the local system,
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media storage.
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So you just got that folder and act as if it was the same drive
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on the desktop or whatever it was.
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And it's sitting right there in front of me.
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Dead easy news.
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Just tunnels kind of look a bit more complicated.
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You've got the, you know,
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SSH, when we used earlier to connect the system,
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and get a log in and log cleanly.
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This time we specify the ports we want.
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So you type SSH, the port you want to forward to.
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Forward from.
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The local host, which is the machine you were actually on.
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And then the port you want to forward to.
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This can be different.
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They don't have to be the same.
|
||
|
|
Unless the remote server you want to connect to.
|
||
|
|
For example, one, one, two, one, six, eight,
|
||
|
|
one point, two or something.
|
||
|
|
And you can add your dash-elf or username or dash-p for your port,
|
||
|
|
if you want.
|
||
|
|
And this creates a sort of a peer and it'll disappear.
|
||
|
|
And what it's created is a create the connection.
|
||
|
|
And now you do as you point your browser to the proxy,
|
||
|
|
Fox 5 proxy, and point it to that port on your local machine.
|
||
|
|
And it'll fire the connection right through to the remote machine.
|
||
|
|
And you can see your web pages and put your data back in there.
|
||
|
|
Which is what we would use to secure Wi-Fi on the Wi-Fi network.
|
||
|
|
So that's basically SSH.
|
||
|
|
There's more that you can do and there's more tools to help you do that.
|
||
|
|
And if you want more information, please don't feel,
|
||
|
|
don't hesitate to contact me.
|
||
|
|
Does anybody have any questions?
|
||
|
|
No, a question is sort of, you can use X-forward in cross-platform
|
||
|
|
so you could forward a line into path,
|
||
|
|
but some people ask that one of you server,
|
||
|
|
and you can put forward it to Windows,
|
||
|
|
but you have to have...
|
||
|
|
Yeah, but you need the next server on the Windows desktop,
|
||
|
|
something like the, of course it's called again.
|
||
|
|
X-Ming, yeah, that's one.
|
||
|
|
There's two or three open source variations.
|
||
|
|
X-Ming is one of them.
|
||
|
|
You can also use Sci-G-Win and install X onto that.
|
||
|
|
Sci-G-Wins, like...
|
||
|
|
Basically, we've taken a lot of Windows 2,
|
||
|
|
a lot of Linux 2s and stuff,
|
||
|
|
put them all together into...
|
||
|
|
You've got to turn on SSH and stuff like that.
|
||
|
|
And you can install, you can install X,
|
||
|
|
you can install Kiri, no, whatever you want, on a Windows system.
|
||
|
|
And one more of the things you can do,
|
||
|
|
you can forward to the X system from that as well.
|
||
|
|
There are proprietary versions out there,
|
||
|
|
but we're not going to talk about that.
|
||
|
|
If you've mounted a father's over at his age,
|
||
|
|
did you use a standard old man command to...
|
||
|
|
Don't man it, what do you mean?
|
||
|
|
No, he needs to use a...
|
||
|
|
Especially when he needs to use a fuser mind command.
|
||
|
|
This fuser mind dashed you slash media storage,
|
||
|
|
as you would have it.
|
||
|
|
Yeah, man.
|
||
|
|
But I mean, one of the great things,
|
||
|
|
I don't know if anyone's discussed this one,
|
||
|
|
one of the great things I always thought about Linux and the gel.
|
||
|
|
If you've got a command you're going to use,
|
||
|
|
and you can't remember what the switch is,
|
||
|
|
what the bottom is,
|
||
|
|
or what the command name is for something.
|
||
|
|
If you type man space in the name of the command,
|
||
|
|
you'll get a small docking man page,
|
||
|
|
and the man that's just lists the basic usage,
|
||
|
|
basic commands in the short script.
|
||
|
|
It's not something we tend to talk about a lot,
|
||
|
|
but we really should.
|
||
|
|
Anyone have any questions?
|
||
|
|
Go.
|
||
|
|
Well, thank you all.
|
||
|
|
Thank you for listening to HACRA Public Radio.
|
||
|
|
HPR is sponsored by Carol.net,
|
||
|
|
so head on over to C-A-R-O dot N-E-C for all of her TV.
|
||
|
|
Thank you.
|