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Hi, Gerbils. I'm out for a POS system these days and I've come across LemonPOS. Not sure if it's any good so I'm trying it. It's built for Linux distros so I had to download and install VirtualBox so I could run it inside a VM instead of getting a new PC right away. The VM I'm planning to run it on is using Ubuntu 11.10 (will get a newer Ubuntu version later on). VB asked me how much disk space to allocate to the VM so I went ahead with 8GB (fixed size). I then allocated around 4GB for the root (/) partition and the other 4GB for the /home partition. After installing Ubuntu, I then proceeded to get the KDE (LemonPOS requires it for some reason) environment with the 'sudo apt-get...' command. Problem is, the KDE installation stopped because I apparently ran out of disk space on my VM. The KDE download is supposedly just around 700MB but it seems 4GB isn't enough for the extracted files. So I'm back to square one and created a new VM and this time allocated 32GB for it. During the Ubuntu installation I allocated 20GB for / and the rest to /home.

Now the question is: when one installs applications under Ubuntu, where does Ubuntu put the files? Is it under / or /home or somewhere else? I'm gonna install MySQL after KDE so I need to know where to allocate disk space the most. Btw, how much minimum disk space does MySQL require? Thanks in advance, guys.

it depends, here's a good place to start learning about this kind of thing:
https://en.wikipedia.org/wiki/Unix_directory_structure

generally speaking software installed through apt will be somewhere under /usr but there's nothing stopping you installing non apt user specific software in /home (this is what Steam does under Linux (much to the annoyance of some people)) or in a directory you create yourself.

NB once you've installed mysql you will also have data stored in /var/lib/mysql since by default that's where mysql keeps its database files on ubuntu.

Since you're just playing around in a VM at the moment you might consider just having a single partition for everything then working out a partitioning scheme when you've got a better idea of what's going on.

Until you get a better feel for how Linux works, you're probably better off having a single file system for / and /home, and configuring VirtualBox for a larger (16-32GB), but dynamically sized virtual disk. VirtualBox will only use as much space on the host filesystem as it needs to store files actually written to the virtual disk. That way you don't need to worry (as much) about disk space issues.

When installing from the distro's repo, executables usually go under /usr, system-wide configuration files under /etc (think of /etc as the equivalent of the Windows registry), and shared dynamic data (e.g. Web pages for Apache, database files for MySQL...) under /var. Third party applications (not from the distro's repo) usually install to /opt.

Per-user configuration and data files will always go somewhere under your home directory, typically in a hidden subdirectory whose name starts with a period.

You probably want to create a bin subdirectory under your home directory, to hold any scripts you create for yourself. If this subdirectory is present on login, the system should automatically add it to your search path.

Edit: Oh, and yes KDE is a resource pig, both disk and RAM. It is basically the "everything plus the kitchen sink... and the hot tub, swimming pool, and wet bar" of Linux desktop environments. Since this VM is (I assume) going to be primarily used to try out some server software, you could get away with a much lighter weight desktop. You may want to look into XFCE (or LXDE, which is fairly minimalist) instead. Or tough it out and go pure CLI... if you install the OpenSSH server in the VM and PuTTY on the host, you can just open a bunch of PuTTY CLI windows into the VM and not bother with a native GUI in the guest.

LemonPOS requires KDE because Qt is the GUI toolkit that it uses.

To save space, you're better off switching to the KDE as the desktop environment, and you'd be better served by switching to OpenSUSE if you're going to be using KDE. OpenSUSE has one of the top, if not the best, KDE implementations.

As JBI said, setup a 16-32GB dynamic disk while you get your feet under you and figure out what you'll actually need as far as resources go. Here is how I would setup the partitions with a 24.5GB disk.

/ -> 20 GB
swap - > 0.5 GB (You shouldn't be swapping, and this thing isn't going to hibernate.)
/home -> 4 GB

File location is really a crap shoot under Linux. Unlike the BSDs which enforce a strict differentiation between system and user programs, Linux programs kind of go all over the place, but generally they end up under "/". Some programs will end up under "/usr" because the maintainer felt that was more appropriate. Then there are the weird ones, like Bind, that use "/var".

will show you how much space is used and how much free for all file systems.

KDE is a horrible thing. Avoid it.

Linux install binaries go in /usr/bin and system binaries generally go in /bin and /sbin. It is appropriate to put user installed binaries into either /home/whateverpleasesyou or for system wide use in /usr/local/bin it is also appropriate to use /usr/local for user installed stuff. Any Linux system should look there as well as higher in the tree. /usr/local/lib should be in ldconfig.

/var is for stuff that varies ... eh'. So logs, webspace etc should go there.

/etc is nothing at all like the awful windose registry. It is simply where configuration is handled in all it's incredible variety.

You can do whatever you want but a standard system setup will be well handled by any normal install.

It is set up the way it is for clarity and to make it easy to hang different parts of the file system on different partitions. If /var/www for instance has it's own space it's easy to change it to a larger one with little impact.

PenGun wrote:

KDE is a horrible thing. Avoid it.

Guess you missed

ronch wrote:

Hi, Gerbils. I'm out for a POS system these days and I've come across LemonPOS. Not sure if it's any good so I'm trying it.

-and-

Flatland_Spider wrote:

LemonPOS requires KDE because Qt is the GUI toolkit that it uses.

As crazy as it may seem to you, sometimes people have specific applications they need to run on their system that aren't on your "PenGun Approved Software" list. Sometimes that software even requires (*gasp*) MS Windows!

That said, if LemonPOS relies on Qt it should still be possible to install just the Qt dependencies without dragging in the entire KDE desktop environment, if that is what's desired.

I actually worked on a POS for a while. I spent a fair amount of time polishing it's HTML interface and making that work better. The only reason anyone would implement a Qt based KDE UI for a POS is to learn Qt. An almost crazy thing to do.

Anyway I did say of KDE: "avoid it". I was mainly explaining Linux file structure to several people.

Flatland_Spider wrote:

As JBI said, setup a 16-32GB dynamic disk while you get your feet under you and figure out what you'll actually need as far as resources go. Here is how I would setup the partitions with a 24.5GB disk.

/ -> 20 GB
swap - > 0.5 GB (You shouldn't be swapping, and this thing isn't going to hibernate.)
/home -> 4 GB

+1 Though I personally would do my partitions differently, that's certainly the way to go for a VM that's for experimenting.

Flatland_Spider wrote:

To save space, you're better off switching to the KDE as the desktop environment, and you'd be better served by switching to OpenSUSE if you're going to be using KDE. OpenSUSE has one of the top, if not the best, KDE implementations

I've not used Suse much (RH and Ubuntu is what I'm familiar with), but doesn't Suse offer better Windows/mixed environment tools, too?

Though KDE is "worse" than most other desktop environments in resource usage, it's not like an even remotely modern computer should have too many issues with it. I know a few people that prefer it. Unity is even "worse," but it's what converted my wife. Personally, I'm a Unity and XFCE person. There is a lot of KDE bashing going on here. But if you like it, and it works, use it.

A bit of searching shows Fedora has a LemonPOS package available, too, if you feel like going the Fedora route.

1. On-topic: If LemoPOS is a Debian-derived distro (and any Ubuntu derived distro is also Debian derived by definition), then look at the dpkg-query utility to tell you where packages want to install files. The other posters are generally right that most files end up under /usr, but some third-party applications might end up under /opt.


2. Off-topic about other posters have said: I've been using KDE since it was beta testing for KDE 2.0 (BACK IN THE 20TH CENTURY!). It's a very powerful desktop that runs just fine on even relatively old hardware (think 5 year old Core 2 + 4 GB of RAM, and it could live with less RAM if you are running it for a single-purpose application like a POS terminal). KDE in its vanilla form has an interface that is relatively familiar to a Windows user (there's a start menu, there's a taskbar, files can go on the desktop in addition to other widgets called "plasmoids" etc.). The Qt toolkit that KDE uses is also an extremely powerful GUI programming system that is cross-platform and is growing in popularity in a wide-range of applications. Don't let anyone tell you that KDE is some terrible desktop, especially when the alternatives are Gnome or Unity.

Losergamer04 wrote:

Though KDE is "worse" than most other desktop environments in resource usage, it's not like an even remotely modern computer should have too many issues with it.

Yeah, but he's running it in a VM so he's got host overhead as well. If he wants the host and the guest OSes to both stay responsive he'd better be overspecced on his RAM or one (or both!) of the OSes are going to start hitting their respective pagefiles with KDE in the mix.

Losergamer04 wrote:

I know a few people that prefer it.

I actually prefer it these days for full-blown desktops, since GNOME killed off GNOME 2. For VMs I set up for a specific purpose -- e.g. building/testing software for another distro -- I tend to use LXDE unless there's a need for a specific desktop environment.

Losergamer04 wrote:

Unity is even "worse," but it's what converted my wife. Personally, I'm a Unity and XFCE person.

Unity isn't that bad on resource usage (which is what I was bitching about), but it can be pretty annoying if you're accustomed to a "traditional" desktop (Windows XP/Vista/7, GNOME, KDE).

Losergamer04 wrote:

There is a lot of KDE bashing going on here. But if you like it, and it works, use it.

As noted above, I actually do use it (on a daily basis). But I still think its resource usage is obscene.

Losergamer04 wrote:

Flatland_Spider wrote:

To save space, you're better off switching to the KDE as the desktop environment, and you'd be better served by switching to OpenSUSE if you're going to be using KDE. OpenSUSE has one of the top, if not the best, KDE implementations

I've not used Suse much (RH and Ubuntu is what I'm familiar with), but doesn't Suse offer better Windows/mixed environment tools, too?

I mess around with it with, but I'm more of a RH guy. Yeah, SUSE does have really good Windows integration. RH integration isn't bad once you figure out the quirks of authconf, but SUSE is really easy. It's on par with adding a Windows machine. Oddly, Ubuntu is quite possibly the worst one for integration.

Though KDE is "worse" than most other desktop environments in resource usage, it's not like an even remotely modern computer should have too many issues with it. I know a few people that prefer it. Unity is even "worse," but it's what converted my wife. Personally, I'm a Unity and XFCE person. There is a lot of KDE bashing going on here. But if you like it, and it works, use it.

KDE needs a video card with good drivers. Without that, it's going to be a bad experience, but luckily, the Linux video driver situation has improved dramatically.

It's matured very nicely from the initial 4.0 release, and it's my second favorite of the heavy weight desktop environments after Cinnamon. Gnome 3 and Unity do really deserve the bashing they get.

A bit of searching shows Fedora has a LemonPOS package available, too, if you feel like going the Fedora route.

I don't recommend running Fedora on production systems. It's a nice desktop, and it's what I normally run. However, it's not built for the long run. The 18 month support cycle is too short, and things can change quite a bit between releases at times.

Flatland_Spider wrote:

I don't recommend running Fedora on production systems. It's a nice desktop, and it's what I normally run. However, it's not built for the long run. The 18 month support cycle is too short, and things can change quite a bit between releases at times.

Yup. If this is going to a production machine and you want a Fedora/Redhat-based distro you'd be better served with CentOS or maybe Scientific Linux, both of which are derivatives of Red Hat Enterprise Linux & thus get long-term support... but if there's Real Money involved you'll want actual support of the type Red Hat themselves provide, so you'd want real RHEL.

Continuing off-topic:

just brew it! wrote:

Unity isn't that bad on resource usage (which is what I was bitching about), but it can be pretty annoying if you're accustomed to a "traditional" desktop (Windows XP/Vista/7, GNOME, KDE).

I agree, it's not THAT bad. http://www.phoronix.com/scan.php?page=a ... 8way&num=1 It changes, usually for the better, with every release. Steam/TF2 runs just fine for me.

Back slightly on-topic:
Canonical is doing some funny stuff with X, XMir, and Mir in 13.10 forward. If used for production, I would stay away from Ubuntu for a little while. It's bleeding edge stuff and only Canonical is using it right now. I'd be leery of the security implications, especially since this is a POS system. I like Ubuntu and all, but their distro isn't supported by a lot of money, unlike Red Hat (Fedora) or Suse (OpenSuse).

CentOS is likely your best bet if you want free and decent security and support.

Ubuntu 12.04 LTS should be a relatively safe bet (supported until 2017 and pre-dates the X/Mir craziness). Or Debian 7.x if the OP wants to move away from Ubuntu but prefers something that is more similar to Ubuntu than Red Hat and its derivatives. I would not use Ubuntu 11.10 for anything at this point, as support for it has already ceased.

Edit:

PenGun wrote:

/etc is nothing at all like the awful windose registry. It is simply where configuration is handled in all it's incredible variety.

The point I was trying to make is that it is where most system configuration information is stored, and it is organized hierarchically with subtrees of information for specific subsystems. In that sense, it serves largely the same purpose as the registry.

I do agree that the implementation is superior. Using the native filesystem and (for the most part) flat text files to store the actual configuration data simply makes more sense than using a set of opaque, proprietary, binary blobs. Recovering from 99% of system configuration screwups (even major ones) requires nothing more than the ability to boot the system to a command line (using a rescue CD/thumbdrive if necessary), and a copy of vi.

Until you get idiots like InstallAnywhere dropping their configuration in a hidden file in /var....

just brew it! wrote:

The point I was trying to make is that it is where most system configuration information is stored, and it is organized hierarchically with subtrees of information for specific subsystems. In that sense, it serves largely the same purpose as the registry.

Anybody who's not a complete fanboy moron got your point.

Losergamer04 wrote:

I like Ubuntu and all, but their distro isn't supported by a lot of money, unlike Red Hat (Fedora) or Suse (OpenSuse).

People can buy support for Ubuntu from Canonical. (http://www.canonical.com/enterprise-ser ... -advantage)

Now, if you mean supported by a profitable company, that's different.

What is this "support" you speak of. I have no experience with this concept. It's probably a windose thing.

PenGun wrote:

What is this "support" you speak of. I have no experience with this concept. It's probably a windose thing.

This kind of Linux advocacy doesn't do anyone or anything any favors, so howsabout we just don't go down that road?

Favors? Huh? You think you may be talking to some one who cares about Linux advocacy?

I'm the user hostile guy remember? I did once try to get support for Big Electric Cat many years ago. That experience taught me there is no support. So I have relied on myself and lo, I am support around here. Partly because of this I took up Linux when NT 4 came out and have happily, with the help of many people on forums etc, solved all the problems that have beset me.

With Ubuntu and a plethora of user friendly distributions I have hard evidence that Linux is being dumbed down. Because of this Linux is less useful as a way to learn about *nix" and computers in general. Since I see things like "oh that didst is not updated often enough so it must be insecure" on a regular basis I conclude no one is learning much.

Because of all this I care not at all if anyone uses or does not use Linux. It's for people who want to learn some things so "support" is not anything I care about.

YMMV

PenGun wrote:

With Ubuntu and a plethora of user friendly distributions I have hard evidence that Linux is being dumbed down. Because of this Linux is less useful as a way to learn about *nix" and computers in general. Since I see things like "oh that didst is not updated often enough so it must be insecure" on a regular basis I conclude no one is learning much.

The fundamental issue is that *you* view Linux primarily as a learning tool, and this is at odds with how most of the rest of the world views Linux today. As a percentage of Linux users, people with this point of view are a small (and shrinking) minority. To you, I'm sure that's a bad thing. To me, it is a testament to the flexibility and extensibility of the Linux ecosystem. If you want to do everything from scratch and build your packages from source, you can still do that; if you'd rather have a pre-packaged distro (or even paid support!), that's available too.

PenGun wrote:

Because of all this I care not at all if anyone uses or does not use Linux. It's for people who want to learn some things so "support" is not anything I care about.

If this is truly how you feel, then why engage in the constant anti-MS trolling?

You misunderstand. I am happy for anyone to do what they want with Linux. As with windose I will mock lameness if I feel like it. When you have something that's dumb to the core, use it for your stupid work. The dumification of Linux is a shame though. Like hooking up a thoroughbred to a cart. Go ahead but I don't have to like it.

You want me to leave windows alone because it's used by a lot of people? It richly deserves most of the scorn directed it's way. As Linux becomes more like it and grows up I'm sure it will deserve lots of it's own. Nothing like users to ruin everything good, clean and elegant. Look what happened to FreeBSD, it turned into OS X, a real horror story.

PenGun wrote:

Favors? Huh? You think you may be talking to some one who cares about Linux advocacy?

well, it was that or someone who was merely engaged in openly narcissistic and absurdly abrasive personal advocacy.

If you are just preening about how great you are because you use linux, uh, OK?

PenGun wrote:

I'm the user hostile guy remember? I did once try to get support for Big Electric Cat many years ago. That experience taught me there is no support. So I have relied on myself and lo, I am support around here. Partly because of this I took up Linux when NT 4 came out and have happily, with the help of many people on forums etc, solved all the problems that have beset me.

Oh, so there is no "support", except for, you know, you. Because while you are self-proclaimedly "user hostile" you are also somehow helping people use Linux. Primarily by denigrating the completely suitable analogies of others who actually helped first, while simultaneously indulging in unreserved "MS with a dollar sign" levels of eye-rolling trolling.

Thanks!

PenGun wrote:

ith Ubuntu and a plethora of user friendly distributions I have hard evidence that Linux is being dumbed down. Because of this Linux is less useful as a way to learn about *nix" and computers in general. Since I see things like "oh that didst is not updated often enough so it must be insecure" on a regular basis I conclude no one is learning much.

No. Clearly the only person who has ever learned anything, ever, is you. Thanks for dropping by to share your magnificence. That really helps us, seeing as how our major issue is our ignorance of your greatness.

Seriously though, Linux is a lot of things to a lot of people. I don't really care if it is "being dumbed down" and it's a false dichotomy anyway. What "dumbed down" distro has ever prevented anyone from just living in the CLI if they wanted? It's all up to the user, isn't it? What's wrong with that?

Furthermore, people weren't talking so much about security as they were maintainability. My impression of the discussion is completely the opposite of yours. People were advocating things like Ubuntu LTS precisely because it wasn't being "updated" to the bleeding edge every 12-18 months. They were specifically valuing a stable environment over the latest and greatest every 6-9 months.

PenGun wrote:

Because of all this I care not at all if anyone uses or does not use Linux. It's for people who want to learn some things so "support" is not anything I care about.

The only thing you care about is having a bunch of anonymous people on the internet hear how great and amazing you are. You must be utterly unconcerned about whether or not any of them actually believe it, because we're getting fed up with this nonsense of yours. If you'd contribute something other than empty self-praise maybe you'd have a better reception around here.

PenGun wrote:

You misunderstand. I am happy for anyone to do what they want with Linux. As with windose I will mock lameness if I feel like it. When you have something that's dumb to the core, use it for your stupid work. The dumification of Linux is a shame though. Like hooking up a thoroughbred to a cart. Go ahead but I don't have to like it.

You want me to leave windows alone because it's used by a lot of people? It richly deserves most of the scorn directed it's way. As Linux becomes more like it and grows up I'm sure it will deserve lots of it's own. Nothing like users to ruin everything good, clean and elegant. Look what happened to FreeBSD, it turned into OS X, a real horror story.

You really need to don the hairshirt and move in with RMS.

There will always be the small sect of hairshirt Linux. The rest of us will just get our stuff done without needing to examine every nut & bolt and not a one of us will care in the least about your dire imprecations. I know that makes us clusers in your book; so be it.

EDIT: Great post, Glorious. [/non-mod]

PenGun wrote:

You misunderstand. I am happy for anyone to do what they want with Linux. As with windose I will mock lameness if I feel like it. When you have something that's dumb to the core, use it for your stupid work. The dumification of Linux is a shame though. Like hooking up a thoroughbred to a cart. Go ahead but I don't have to like it.

The people who talk like this are, universally in my experience, bitter dilettantes.

No one cares what you like. No one was even advocating windows here anyway, it's completely orthogonal to the discussion. Windows was only used as analogy, completely appropriately considering that's what most people are familiar with. Instead of handling that like an adult, or even just ignoring it, you decided to gratuitously insult one of the most genteel and respected linux users on this forum. He might be characteristically too gracious to acknowledge the offense, but it didn't go unnoticed or unappreciated.

PenGun wrote:

You want me to leave windows alone because it's used by a lot of people? It richly deserves most of the scorn directed it's way. As Linux becomes more like it and grows up I'm sure it will deserve lots of it's own. Nothing like users to ruin everything good, clean and elegant. Look what happened to FreeBSD, it turned into OS X, a real horror story.

Actually, we want you to "leave windows alone" because it really isn't the subject of the discussion here.

I really have no idea where you are going with this. I use Linux and VMS every day at work, and Linux every day at home. I honestly have no idea what you are talking about in regards to Linux becoming more like windows. Certain desktop environments? Sure, but if you confuse that with Linux itself then *YOU* are the pretentious idiot you merely pretend to denounce.

User hatred is likewise. I don't know why you want to worship whatever twistedly demented idol you only think is called Linux, but outside of a solipistic religion of self-flagellation the entire point of OSes is to enable and facilitate users. For chrissakes, you're a user too you filthy heathen.

And OSX and FreeBSD? Please.

PenGun wrote:

With Linux and a plethora of user friendly distributions I have hard evidence that Unix is being dumbed down. Because of this Unix is less useful as a way to learn about *nix" and computers in general.

Fixed that for you.

Being too user friendly has been a knock against Linux from the start, and it's one of the main reasons that it really took off. As great as Solaris is, it was a b**** to work with, and that's the reason Sun hired the founder of Debian to modernize Solaris.

This is ancient stuff. Source vs Binary, BSD culture vs Linux culture. Back in the day, those were some hot button topics.

There is Minix, which Andrew Tanenbaum specifically wrote for teaching people about operating systems. Then there is NetBSD which is clean and portable, and then there are all of miscellaneous pet OS projects out there and wiki.osdev.org.

Since I see things like "oh that didst is not updated often enough so it must be insecure" on a regular basis I conclude no one is learning much.

That's the Linux culture. Linux: Just hack it. BSD: Engineer it correctly from the start. The BSD guys used to love throwing that one out there. It's amazing how a large market share can codify bad practices.

PenGun wrote:

Look what happened to FreeBSD, it turned into OS X, a real horror story.

Nothing happened to FreeBSD. It's still there. http://www.freebsd.org

OS X is a Chimera, and it's roots go back to NeXTSTEP and Carnegie Mellon's Mach kernel, both of which were conceived, and released to production, well before Linus started on Linux. (Fun fact, Apple actually toyed with using the Linux kernel as the basis for their operating system after System 9 before buying NeXT and producing OS X.) OS X borrows various tools and ideas from various projects, but so does Linux.

Admittedly, the Mac guys won a few too many battles really neutered OS X's Unix credentials.

Flatland_Spider wrote:

Admittedly, the Mac guys won a few too many battles really neutered OS X's Unix credentials.

...completely aside from the fact that OS X is a certified Unix.

That said, we've wandered well afield of the OP's questions and IMO this crap ought to be split out. Funny how that happens when an idiot fanboy has to put his two cents in.

Wonderful. Two Glorious responses and an accusation of being mean to someone. Almost universal revulsion as well.

A few of us answered his question. Where the binaries go. I was one.

The problem you have is me laughing at "support". As I said it's not a thing I have ever used. Back when we had to _build_ a LAMP stack, and you had to build it together in the right order, there was no support outside of a few hints from the coders and people involved. Support did not exist in Linux till ... I guess Red Hat got all commercial. Man pages baby. That's support.

Heading for a lock. Back on topic please.