Ownership and Access Permissions
Two of the more frustrating aspects of Unix-like OS's for Newcomers are file ownership and access permissions. The scheme is relatively simple and highly robust, but can lead to "invisible" problems and unexpected frustrations at times. Basic Linux tutorials usually discuss these aspects of operation; a short but useful explanation is given in Chapter 14 of the RUTE document .
A common problem is that various processes in Linux operate as independnet Users, and hence are assigned their own User ID and permissions. Problems can occur when they are required to access, and especially to alter files belonging to other Users, or to root. There are various workarounds to these difficulties such as using the sudo command which, when correctly set up, allows any command to be run as root or another User.
The easiest solution is to run as root all the time. This has certain risks for Newcomers, but for those confident of their abilities and/or prepared to accept all consequences of their actions, including mistakes, it completely obviates all problems of access and permissions. This Author has run as root now for more than a dozen years without any adverse consequences.
Separating personal data from the Operating System
It is a very good idea to separate your personal data from the OS by keeping it in a separate partition or on a separate device. Very large HDDs are now quite inexpensive, and my personal setup uses two:
- sda is the OS Drive; a 160GB SATA drive having twelve partitions, a 4GB swap partition, and the rest about 16GB contatining various distros and versions of my usual Gentoo installation.
- sdb is the Data Drive; a 1TB SATA drive having a single ext3 partition containing all of my data.
Here is one way of using this. Create a new root directory; I call mine work since this sorts to the bottom of the root directory list as at right. Mount the second HDD on it using the following entry in /etc/fstab:
/dev/sdb1 /work ext3 defaults 0 0
Most Linux distros create several directories in the User's Home Directory such as Desktop, Documents, Movies, Music and so forth. Move these directories onto the Data Drive using either Midnight Commander or the mv command. Then change to your Home Directory and create a series of softlinks to each directory on the Data Drive:
># cd ># ln -s /work/Desktop ># ln -s /work/Documents ># ln -s /work/Movies ># ln -s /work/Music
Linux can be configured to run on a wide range of hardware platforms, from single-board 386 industrial controllers through high-end Pentium and AMD processors, and on to SPARC's, IBM mainframes and the latest 64-bit microprocessors. However, the low-end platforms cannot efficiently support complex applications. As a general guide:
- A machine with less than a 120MHz Pentium and 32MB of RAM cannot run X-Windows at usable speed. It can still run Linux, but only with text-mode applications.
- If you want a Windows-type Graphical User Environment (GUE or GUI) the minimum is a 120MHz processor, 32MB of RAM, and a 1.2GB hard disk drive (HDD). This class of machine cannot run the latest GUE Desktops such as KDE and Gnome. Instead, either switch to an earlier distro such as Mandrake 6.2, use one of the excellent light-weight Desktops such as Xfce, or use a light-weight Window Manager (Blackbox, Fluxbox etc.) with light-weight applications.
- Machines with at least an 800MHz CPU, 64MB of RAM and a 2GB HDD run KDE, Gnome, Open Office and other heavy-duty environments and applications satisfactorily.
- The more RAM the better up to about 512MB. A machine for daily semi-professional use should have a 1GB or better CPU, 256MB of RAM, and at least a 4GB HDD.
CDROM's, DVD's and burners
Linux supports all ATAPI (IDE) CDROM drives, and some of the older configurations in which the CDROM connected to the sound card. ATAPI drives connect to the HDD ribbon cable and "look like" a HDD to the OS, thereby making them simple to support and enabling them to be used as boot devices. CD burners and DVD drives are also supported, but software drivers can be a few months behind the mainstream market. For most users this is not a problem, since it is generally unwise to purchase the very latest technology, and better to wait until any early bugs have been identified and fixed. A number of websites maintain up-to-date information on all aspects of Linux development, and those who need to use the latest equipment should avail themselves of the information so available. See the Links Page for more information.
Printers, scanners and faxes
The situation with these peripherals is much the same as with CD's and DVD's. For comprehensive information, see www.linuxprinting.org
Digital cameras, videocams and webcams
Again, much the same as for other peripherals, but even more dependent upon driver availability. Check the Net for details of any equipment of which you're uncertain.
Sound, music and MIDI
Linux has a huge range of sound and music applications. See www.linux-sound.org for a comprehensive list.
Linux is the OS par excellence for networking applications. Check the Networking-Overview-HOWTO for details.