Suggest a USB-installable Linux distro to try on a 256MB RAM PC

prowla

Kernel_Sanders wrote: »

Still trying to get my Microsoft-indoctrinated mind around this!
So what is the point of root in Linux? Is it anything more than just a / ?

Think of the directory structure as a tree structure with "/" at the top (ie. the root of the tree); under that you will have /home, /tmp, /var, /usr, and so-on; under those there will be more directories.

The system must at a minimum have one disk (a physical drive or a ramdisk) mounted at "/", and any of the directories (except for a couple of special ones, like "/dev" & "/proc") could be another disk that is mounted at that point. There is no C:, , .. Z: on UNIX Linux - you can have as many as you like.

The big advantage of this is that you don't need to know the disk layout in order to use the system, or in other words the role of user and the role of adminstrator have been separated; the user gets a consistent view of the system which the administrator has configured. This means that from the user's perspective little desktop systems with an internal SATA drive and large data centre back-end systems with terabytes of SAN-based storage look and behave identically.

A good Linux distro will let an inexperienced user don the hat of "administrator" and configure a system quite easily.

Kernel_Sanders

prowla wrote: »

Think of the directory structure as a tree structure with "/" at the top (ie. the root of the tree); under that you will have /home, /tmp, /var, /usr, and so-on; under those there will be more directories.

But this is exactly how I think of the Windows hierarchy; / is My Computer while /home, /tmp, /var, /usr and so-on equates to A, C, D. E etc. The only difference seems to be that Window's letters relate to different volumes.
Also, I've never read any explanation as to why hardware has to be mounted' in Linux.

prowla wrote: »

The big advantage of this is that you don't need to know the disk layout in order to use the system

IDU this at all. Given that you have a graphical interface, can you say what things you would be unable to do in Windows unless you knew the layout of the hierarchy?

esuhl

Kernel_Sanders wrote: »

But this is exactly how I think of the Windows hierarchy; / is My Computer while /home, /tmp, /var, /usr and so-on equates to A, C, D. E etc. The only difference seems to be that Window's letters relate to different volumes.

"My Computer" isn't a directory, it's just the way that the GUI represents the folder hierarchy, so it's a bit different to the Linux root directory. And /home doesn't "equate to" a specific drive letter; it's closes equivalent is Windows' virtual folder "My Documents".

In Windows, you need to know how the hardware has been mounted (i.e. which drive letter) relates to the device you want to access. In Linux, /home could be on a single hard drive, or spanned across 100 hard drives, but this is hidden from the user (as there is no need for the user to be aware of such distinctions -- they just need access to their files, however they are stored).

Kernel_Sanders wrote: »

Also, I've never read any explanation as to why hardware has to be mounted' in Linux.

A drive needs to be mounted no matter what operating system you use. In Linux this is done by using the "mount" command or /etc/fstab, etc., to attach the device to the existing filesystem hierarchy. In Windows, drives are mounted by assigning drive letters.

When you want to eject a USB flash drive (and have file caching enabled), you need to click the icon in the system tray to "safely remove" the device. What you're doing here is explicitly flushing the cache and unmounting the device.

Kernel_Sanders wrote: »

IDU this at all. Given that you have a graphical interface, can you say what things you would be unable to do in Windows unless you knew the layout of the hierarchy?

Linux is really just the kernel; the GUI (Window Manager or Desktop Environment) is an extra layer that sits on top of the operating system. Many Linux systems don't have a GUI at all. But (more-or-less) anything you can do from the GUI you can do from the command line.

Linux is designed to be modular and extensible, and consideration has always been given to the fact that it could be running on a computer with many hard disks and users. In such cases, the system administrator would be responsible for maintaining/configuring the hardware, but the end user shouldn't really have to know anything about what hardware is being used... All they need to know is what they can do with the hardware and how to access their files. The abstraction of the directory hierarchy from hardware references makes interaction with the system simpler for the end-user.

Windows, on the other hand, was originally designed as a DOS shell for use on personal computers with a single user. Subsequent versions may have been written more-or-less from scratch, but there has always been a need to maintain backward-compatibility and so the original "single-user, no security" model has been tweaked and hacked to provide the extra features, rather than being scrapped and replaced with a Linux-like multi-user model. Basically, Windows has been designed from the bottom-up and new features have been added to a model that was never designed to include them in the first place; Linux was designed with multi-user/security features from day one. So Windows is, in many ways, a bit of a bodge job!

I can see why it might seem a bit confusing on a single-user system, though. In most cases the user and system administrator are the same person, you don't have a huge number of hard drives, and the distinctions between Linux and Windows probably seem like some kind of pedantic idealism... but Linux really is much better designed to be used in a wide variety of applications.

Not sure if that helps explain things...

prowla

wot esuhl said...

And the default for Windows is to have users on your C: drive, which means that it is difficult to separate system from users. Shifting that elsewhere is not straightforward. The equivalent in UNIX/Linux is "/home", which can be transparently located on a different filesystem (disk) if you choose.

Kernel_Sanders

prowla wrote: »

wot esuhl said...

And the default for Windows is to have users on your C: drive, which means that it is difficult to separate system from users. Shifting that elsewhere is not straightforward. The equivalent in UNIX/Linux is "/home", which can be transparently located on a different filesystem (disk) if you choose.

My poor brain can't cope with esuhl's reply ATM

To understand yours I need to know if by 'transparently' you mean openly or invisibly.

debitcardmayhem

Kernel_Sanders wrote: »

My poor brain can't cope with esuhl's reply ATM

To understand yours I need to know if by 'transparently' you mean openly or invisibly.

You are giving MTFC (The Stags) and the home town a bad name. Think of mount points /home /usr/local and C: etc as anchors , if you don't have a place to anchor how can you find where to go back to. I want to go to "home" where is that ? is it /home or C:\Users\KS\ . Each of /home /usr/local and C: etc consist of pointers to where the directory is (being a whole disk , a partition or indeed another directory), directories are like indices or a collection of pointers, or simply put how can I find xxxxxxx , but of course you may want to find Mansfield , now where is that , OK which one then Mansfield Notts England , or Mansfield ,Texas US of A? it is all down to pointers , and if you find the file KernelSanders on your disk then having found it, where does it live? it doesn't know because it is just a collection of bits on a medium , it doesn't know the directory it lives in, nor the partition its directory is in, ...... now you can be confused
C: or /dev/dsk/sda1 are pointers, the underlying structure doesn't know about C: or /dev/.... because they do not need to because they cannot know where they could be put(accessed from)

esuhl

Kernel_Sanders wrote: »

My poor brain can't cope with esuhl's reply ATM

Ahh... sorry about that!

Kernel_Sanders wrote: »

To understand yours I need to know if by 'transparently' you mean openly or invisibly.

Everything (well, in terms of basic system administration) in Linux is "open". All relevant hardware information should be visible (i.e. available) to the system administrator.

But there's no need for the user to be concerned with such things. It's not necessarily that the information is "hidden" from the user, they just don't need to be concerned with the details. So, access to files is "transparent" because, to the user, they just come from /home/username... but of course the system administrator will know that the filesystem containing /home/username is actually a 250GB SATA partition identified as /dev/sdh3 that is formatted as ext3, etc., etc.

This is probably a bad analogy (and I'm going to oversimplify it horribly), but imagine the difference between two cars with manual and automatic transmissions...

All the driver (user) wants to do is to get from A to B, but the driver of the manual car needs to "know" a little bit about the gear ratios and which gear is suitable for travelling at a certain speed, and how to use the clutch to disengage the transmission. The driver of the automatic car effectively has two pedals: "go" and "stop"! The mechanic (system administrator) can look at the car and will know how many gears it has, and can change the point at which the car "decides" to change gear, but all of the workings under the bonnet are of no concern to the driver (end-user)... so long as it all works.

Obviously that's a bad analogy because you have more control in a manual car, whereas the abstraction of hardware and directory structure in Linux doesn't (itself) limit the control of the user. It just makes it simpler because every Linux system will appear to have the same kind of coherent structure no matter how complicated (or not) the real hardware configuration is.

Kernel_Sanders

OMG I'm going to have to take time out to study all this!

I'll make a reply next month

Jnelhams

Any idea which flavour of Linux, I can put on an old Toshiba 4090XCDT which has 64mb Ram, 4gb HD and a Micronet USB WiFi Dongle? It was running Windows XP ok, but this was a bit flaky on boot up.

debitcardmayhem

DSL or Puppy , I used to have a version of Slakware about 3 millenia ago on a 64 Mb fujitsu but can't remember which version and it was well before the iron age, but it did run with a Belkin wifi pcmcia card
Edit: it may be worth trying with various "live" isos
http://www.google.co.uk/search?q=linux+on+64mb+ram&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:unofficial&client=firefox-a