Unlike in the Windows world, where Microsoft
decides what type of OS
you need, Linux leavesthe choice to the user, This also has the disadvantage
-a user should be aware of his needs. As a ruleof the thumb, if you are setting
up a server, the Red Hat Linux is the best because the documentation available
for Red Hat is by far the most comprehensive. Debain Linux is also a popular
choice.
If you are a novice who wants to test the Linux waters, choose Caldera
OpenLinux-2.3 or Corel Linux. The installation is amazingly simple and the
available program packages are good too
One important setting in any protected mode OS like Linux
is the swap space.
During the installation, you will need to create a swap partition. A common
question is this: what sizeshould the partition be ?
The proper size depends upon two things-the size of your hard drive and how
much RAM you have. The less RAM, the more swap you will need. Generally
you will want to set your swap to double the size of the RAM. This ofcourse
requires you to have the appropriate disk space free.
Low memory systems require more swap but if you have oodles of RAM
you can get away with less swap.
You installed a new Linux system, but forgot to set enough
swap space for
your need. Don't worry-there'sno need to repartition or reintall Linux. The
Swap utilities in Linux allow you to make a real file and use it as swap space.
The trick is to make the file and tell the swapon program to use it. Here's
how
you can create a 64MB swap file on your root partition.
dd if=/dev/zero of=/swapfile bs=1024 count=65536
This will make a 64MB file on your hard drive. You now need to initialize it:
mkswap /swapfile 65536
sync
And now you can add it to your swap pool:
swapon /swapfile
You now hev 64MB of swap added. Don't forget to add the swapon command
in your startup files so that swap is added at each reboot.
The Linux kernel will detedt various dettings from your
computer configuration.
This includes the size of memory you have.
With some kernel versions, notably the 2.0.x versions, it may find the wrong
size.
For example, it may only find 64MB when in fact you have 128MB installed.
The trick here is to use the "mem" parameter at bootup. Here is what
you should
type at boot, if you have 128MB RAM:
LILO boot: linux mem=128M
This will tell LILO to load linux kernel with 128MB of memory.
If you want to install Windows NT and Linux on the same
machine, you may have
to face a problem because Windows NT has its own boot loader called NTLDR
and Linux has LILO. HWich should go on the MBR ?
The safest way is to install NT first and then Linux with LILO on the MBR. When
the system boots LILO can load the MBR with NTLDR in it.
You need to put LILO in the MBR and not the NTLoader, LILO can load
NTLDR, but NTLDR can;t load LILO.
When a Linux system boots, it loads the kernel, its dirvers,
and the networking
servers, and then the system displays a text login prompt. Here users have to
enter their usernames and passwords. But the system dosen't always have to
boot this way.
There are three modes defined in most Linux distributions that can be used for
booting. They are defined in /etc/inittab and have specific numbers. The first
mode,
also called Runlevel 1, is a single user mode.
It will only boot the system for one user, with no networking. Runlevel 3 is
the
default mode. It will load the network servers and display a text login prompt.
Runlevel 5 is the graphical mode. If you XFree86 installed and configured, you
can
use it to display a graphical login prompt.
The way to change this is to edit /etc/inittab and the initdefault line:
id:3:initdefault:
Changint the 3 to 5 will make the system display a graphical login screen on
boot.
To make the changes effective without a reatart type "init 5" at the
command line.
Note: With SuSE linux 2 is the defualt and 3 is the graphical login.
By default Linux will not allow users to mount drives.
Only root can do it, but with
a special command in the /etc/fstab file, you can change that.
This is a typical line for the fd0 (A:) drive in /etc/fstab:
/dev/fd0 /mnt/drive auto noauto,user 1
1
The keywords here are noauto and user. Noauto tells mount not to try to mount
a
diskette on boot, and user lets you mount the drive into /mnt directory. The
auto
keyword is also interesting, it tells mount to try to find out which filesystem
is on the
diskette.
You could also usr msdos or ext2 if you think you will not be using any other
filesystem.
Remember to password-protect your LILO configuration.
If you do not do this,
anyone can reboot your Linux box and take over your system admin account(root)
immediately without a password-by typing "linux init=/bin/bash ro"
at the LILO
boot prompt.
Just insert "restricted" in the Linux section of your /etc/lilo.conf,
and enter a
password line to restrict access (See lilo.conf man page for details).
This will allow the system to boot normally, but will not allow any boot time
configuration (i.e. bringing the system up in the single user mode or giving
a root
prompt without any password authentication).
A lot of people resist switching to Linux because they
have purchased many
programs for their Windows system and don't want to loose their investment.
The
good news is, you dont have to loose money after all.
Wine HQ (www.winehq.com) has created wine, a Windows implementation under
Linux for running Windows programs. Many office, games and other buisness titles
have been tested under Wine. If you want to see if your application has been
tested
you can ask the Wine Apps database at www.winehq.com/Apps/query.cgi.
When installing new software, many Linux administrators
face the dilemma of
having too little disk space and not knowing why. Here's a quick command that
will
allow you to list the largest files on your system, and figure out what to delete:
cd
ls -lR | sort +4n | tail -X
This uses the ls command with the output piped to the sort command using the
4th
field (file size) as the sorting variable. You then pipe the sort result to
tail and
specify how many largest files you want to see, specified by the number X (for
the
50 largest files, X=50).
Many new Linux users miss familiar interfaces when accessing
the terminal
command line, which is still used quite often when installing software, compiling
programs etc.
If you are familiar with the Norton Commander file manager interface, then you
should definitely download and use Midnight Commander, the GNU equivalent for
Linux (most of the latest Linux distributions include Midnight Commander).
Midnight Commander can run in both console and term sessions under X. Mouse
support is native under xterm sessions and is provides by the gpm mouse server
under console sessions. If you are uncomfortable navigating Linux filesystems,
then
Commander will definitely boost your productivity.
Midnight Commander can be downloaded at www.gnome.org/mc/. Look on your
Linux CD first though. It's most probably already there. Start it by typing
"mc" at
the command line.