I have some knowledge of CGI scripts and how they work and came to thinking that, in theory, it should be possible to run VirtualBox, or any type of virtualization as a CGI script. Understandably, this would be no easy task. For one thing, it's output (the screen of the virtual OS) would somehow have to be converted so that the browser could read it, show it to the user, and then somehow update it without refreshing the page (which would mean JavaScript would be involved, probably).
Does anyone have any suggestions on how one would start a project such as this one? Has this been done/attempted before?
First of all, running a virtual machine as a CGI script is highly unpractical, as it would stop the machine if the connection is broken. Instead, the CGI script should be able to start, stop and control the virtual machine, which would be running in the background.
As for interacting with the virtual machine, VirtualBox has support for remote desktops (through the VNC protocol), which is probably the most suitable method of displaying and controlling it. However, while you can use a combination of server-side and client-side scripting to make this work, this would probably become very slow and use a lot of bandwidth. Instead, you could use something like a Java applet to connect directly to the virtual machine via VNC, which would save much of the hasstle on the server side.
There is also a similar idea called phpvirtualbox, which I haven't look into myself, but you might find it interesting.
Related
Is there any software working like this?
Runs as a standalone program. No install is needed. Thus, can be used as an Ansible module.
After running the program in a remote Linux machine, I can open up a web browser, then open a web page provided by the program. The program provides features similar to file explorer, IDE-level code editor, debugger, etc. In terms of debugger, there is already similar one; gdbgui.
There is another way such as Gnome, KDE or X11. However, these requires much packages to be installed. I don't want they be installed, because my Linux machines are kept to be small and secure.
You might consider having some terminal emulator running inside a browser. Such things exist, e.g. libonion has oterm as an example application. Then you can do all the things that a command line interface thru a unix shell provides (of course, you won't be able to run GUI applications, e.g. X11 clients such as GTK or Qt applications).
You could also consider some webmin like stuff.
Notice that you don't need to have a desktop environment on a remote Linux machine. Most of them (e.g. internet servers) have only command line interface.
Learn more about X11: you could have an X11 server on your laptop (e.g. under Windows if so needed) and run remotely X11 clients (that is GUI applications) with ssh -X on your remote Linux system.
However, these requires much packages to be installed. I don't want they be installed, because my Linux machines are kept to be small and secure.
I don't understand that requirement. On my VPS, running in some OVH datacenter, I do have X11 client applications (notably emacs). I don't believe that lowers the security of my system, and the disk space consumption for X11 applications and libraries is small enough these days. And of course I use standard commands (like cp(1), mv(1), rm(1), grep(1), find(1), less(1), file(1), sed(1) ....) to manage files. Any graphical file manager is useless (and I never use them, while using Unix since 1986)
You really should learn how to use the command line on Linux. It is incredibly powerful.
I am wondering if it is possible to write a program on Windows that communicates with a program within a Linux Virtualbox on the same machine. If this is possible, what is the best approach to doing this? Is there a way to do this without using the internet to communicate?
I found instructions showing how you could potentially use SSH, but I have never tried doing this before, so I do not know if using SSH to communicate would be the best option.
I was going to put this as a comment to a very vague question, but then it got too long.
It depends what you mean by "communicate"....
If the Windows machine should start a program on the Linux VM, you probably want plink.exe - see here.
If you want to transfer whole files, you probably want scp or FTP or FileZilla - see here.
If you want to send small messages occasionally, maybe netcat, also known as nc - see Netcat Cheatsheet here.
If you want full-on, high speed, continuous messages, maybe sockets or some messaging protocol like mqtt.
If you want to share data structures, like lists, queues or sets, you could allow both Windows and the Linux machine to access a shared Redis database - see here.
Or maybe it is enough to share a filesystem between the two machines - in which case you can make a Shared Folder in VirtualBox on your host and the VM can just mount that and read/write it. See diagram:
I want to make a system which would get input from USB barcode scanner, validate it on remote server and display an answer (text and images).
I would use JavaFX or in-browser JS web application to grab scanner input somehow.
I'm planning to run this application on Raspberry Pi or plain PC.
Is there a way (or a special linux distribution) to ensure that system always loads the same way and starts JavaFX app or opens particular web page in browser?
e.g. no login page, NO update or other popups are shown.
Any other ideas? Thanks
...
Found an interesting solution here, where JavaFX GUI app is started from command line, without X-Server(linux graphical interface) at all.
I have recently done something similar, and it's not too hard. Obviously working on the Pi, you will want to use something like Linux and having limited hardware will mean that you should be minimising what you are running. Due to this, I would recomend that you run a light weight distro. Something like arch (which is what I used) allows you to build only what you want from the ground up without the need to find and compile everything like you do for LFS or Gentoo.
As for booting, the following two wikis will give you the details of starting the Gui without manual login:
https://wiki.archlinux.org/index.php/Automatic_login_to_virtual_console
https://wiki.archlinux.org/index.php/Start_X_at_Login
After that, it is simply a matter of putting the command to launch your program in .xinitrc.
I currently have a tiny, headless (and I certainly want to keep it that way :) ) Linux Virtual Machine set up with Vagrant and VirtualBox which, for testing, I want to run an X11 application (Firefox) whose output comes to Xming on my real machine. All that's hunky dory, working perfectly, but I'm not happy yet!
What I want to be able to do is do a few setup things, make sure everything's running correctly, then disconnect from the server and let the testing run it's course. If however something goes wrong, or I want to just check the current status of things (some of the tests may run into hours), I'd like to then hop back onto the server and point the X11 output to my machine again. But despite a good deal of Google-ing and learning loads about X11 that I didn't know a few hours ago, I can't find anything about choosing where the output of an X11 application goes, except at startup, ie;
DISPLAY=:10 firefox &
I had read some random blog post that Xephyr XServer did this (kind of act as an intermediate X11 buffer, which then redirects if you want it to, otherwise just outputs to /dev/null), but I can't find any other reference to it, or anything else doing that.
There's a program called Xpra that works sort of like "screen" but for X-sessions. It would start a separate X session from the main one, for the remote access, but you can connect/disconnect to it at will from the host machine.
http://www.xpra.org/
I currently have one acceptable way to do this, which will serve my purpose, I have a vnc4server running that takes firefox's output, and then I can connect and disconnect to that without any issue at all, just like a normal VNC server. This allows me to do what I want to do, but not how I want to do it. I'd like to be able to do this without the need of a VNC server at all.
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I work in IT (mostly desktop support and network administration) in a Windows environment, and I occasionally program.
A couple weeks ago, I decided I couldn't be as effective as I want to be without a Bash environment for my command prompt needs. This is especially true when I am using Ruby and git. I used Msysgit for a while, but I just didn't like how it wasn't extensible like Linux. So, I installed Cygwin and played around with that for a couple weeks.
As great as Cygwin is, it seems like it is meant to be a suped up command prompt, and its compatibility with Linux is just a pleasant side effect. This especially became evident when I tried to upgrade Ruby to 1.9.3 (it worked, but it wasn't straightforward), install rvm (never worked), and install RMagick (may or may not work, but looks like a headache).
So, now I'm considering running Linux in a virtual machine. But I'm worried that might be another can of worms and I'll have wasted hours before I find that out. I like that Cygwin runs in Windows and I get to use my IDE, user folder, and more with it. But I don't like that support for it is not as thorough as for a major distro.
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Does anyone here have insight on using Cygwin vs running a Linux virtual machine?
Any advice on setting up a Linux development environment in a virtual machine within Windows?
I have faced common issues before, and the best solution according to my experience is just 2 workstations :).
Apart from that having Linux running in a virtual environment is way better.
First of all, you will have full Linux capabilities (except 3d acceleration, but you probably don't need that).
You will have the capability of creating snapshots and revert back to them when things go wrong!
You can start multiple environment using templates, which is very convenient.
The only downfall I can think of is performance issues of the host machine.
If it's a normal workstation/PC, an IDE + one virtual machine + a 100+tabs browser just makes it slow.
1: cygwin is good for quick hacks, and for being able to acces host-os resources(you can run IE for example in a bash script). For something tightly integrated and some "real" word, go to a vm. It will emulate everything and separate development from the real machine, and this may be a good thing in some cases... as a plus it simulates a real server:)
2: in virtualbox at least, you have shared folders, and you can share a local folder, and see it in the vm as a local folder(local or as a windows share..it actually depends). Then you can use that "entry point" to symlink stuff into the vm, and do the things you need with the real files being located in the real(host) machine
SSH into a linux box. This is what everyone does. Why isn't this the answer?
There is something I have heard of called Cooperative Linux. It runs Linux alongside with Windows kernel so you can use them at the same time. I've never used it, but here:
http://www.colinux.org/
What I think now is getting the pros of 2 options is using
Docker
, it is giving you cygwin simplicity and VM functionality with better performance.
Linux in a virtual machine will give you the experience you want more than cygwin or any mock shell as I like to call them.
Running VM's though require a lot of ram depending on whether you want a desktop version of linux or just a command line version.
Myself in work I have a pc with 8gb of ram and I run ubuntu 64bit as main OS, two ubuntu servers (these are for dev environments two different projects) and a windows 7 VM and a win XP VM.
I can run the two ubuntu servers and one other VM at the same time, key here is more ram if you want to be able to do VM's.
If you're going to be working with Ruby then get an Ubuntu virtual machine up and running :) I've not tried Ruby, etc on Windows but I have heard that it is a pain to setup and configure. I use a Mac for all my Rails development so I cannot comment on the Windows side for that.
As for virtual machine creation, I prefer VMware Workstation, however there are free alternatives such as Virtualbox and VMware Server.
I'm using a Linux VM within a Windows seven environment as this VM is as representative as possible of the final production environment. The whole setup is binded to the Eclipse IDE under ms-Windows seven. So this is really great for local full testing, before committing or tagging the tested version to the production servers.
As you mentioned as well, this takes some time to get properly setup and fully configured. So if your need is only for little tricks or tasks, you may keep using cygwin. For example, I faced significant issues to configure perl and compile mysql within cygwin. So it's ok for basic usages, but not to fully take advantage of a full linux environment.
Your choice strongly depends on the final server setup purpose. A VM will do it whatever your need is. The setup cost for it is higher, so this time investment must be used often to get returned.