This book was written in DocBook/XML, and converted to HTML and XSL:FO with xsltproc. The latest version of the book is always available from: http://www.slackbasics.org/.

This section gives a short summary of the conventions in this book.

Hello world!
      

$ command
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1.2.4. Notes

Some sections contain extra notes. It is not necessary to know the information in notes, but notes may provide valuable information, or pointers to information. Notes are printed like this:

	Note
	This is a note.

Linux is a UNIX-like kernel, which is written by Linus Torvalds and other developers. Linux runs on many different architectures, for example on IA32, IA64, Alpha, m68k, SPARC and PowerPC machines. The latest kernel and information about the Linux kernel can be found on the Linux kernel website: http://www.kernel.org.

The Linux kernel is often confused with the GNU/Linux operating system. Linux is only a kernel, not a complete operating system. GNU/Linux consists of the GNU operating system with the Linux kernel. The following section gives a more extensive description of GNU/Linux.

In 1984 Richard Stallman started an ambitious project with the goal to write a free UNIX-like operating system. The name of this system is GNU, which is an acronym of “GNU's Not UNIX”. Around 1990, all major components of the GNU operating system were written, except the kernel. Two years earlier, in 1988, it was decided that the GNU project would use the Mach 3.0 microkernel as the foundation of its kernel. However, it took until 1991 for Mach 3.0 to be released under a free software license. In the the same year Linus Torvalds started to fill the kernel gap in the GNU system by writing the Linux kernel. GNU/Linux thus refers to a GNU system running with the Linux kernel.

The GNU kernel, named “HURD” was still under development when this book was written, and is available as the GNU/HURD operating system. There are some other kernels that are ported to the GNU operating system as well. For instance, the Debian project has developed a version of the GNU operating system that works with the NetBSD kernel.

Slackware Linux is a GNU/Linux distribution, which is maintained and developed by Patrick Volkerding. A distribution is a coherent collection of software that provides a usable GNU/Linux system. Volkerding started using GNU/Linux because he needed a LISP interpreter for a project. At the time the dominant GNU/Linux distribution was Softlanding System Linux (SLS Linux). Slackware Linux started out as a private collection of Volkerding's patches for SLS Linux. The first publicly available Slackware Linux release was 1.0, which was released on July 16, 1993.

In contrast to many other GNU/Linux distributions, Slackware Linux adheres to the so-called KISS (Keep It Simple Stupid) principle. This means that Slackware Linux does not have complex graphical tools to configure the system. As a result the learning curve of Slackware Linux can be high for inexperienced GNU/Linux users, but it provides more transparency and flexibility. Besides that you get a deeper understanding of GNU/Linux with no-frills distributions like Slackware Linux.

Another distinguishing aspect of Slackware Linux, that also “complies” with the KISS principle, is the Slackware Linux package manager. Slackware Linux does not have a complex package manager like RPM or dpkg. Packages are normal tgz (tar/gzip) files, often with an additional installation script and a package description file. For novice users tgz is much more powerful than RPM, and avoids dependency problems. Another widely known feature of Slackware Linux is its initialization scripts. In contrast to most other GNU/Linux distributions Slackware Linux does not have a directory for each runlevel with symbolic links to services that have to be started or killed in that runlevel. It uses a simpler approach in which you can enable or disable services by twiddling the executable bit of an initialization script.

The packages in Slackware Linux are compiled with as little modifications as possible. This means you can use most general GNU/Linux documentation.

Since GNU/Linux is a free reimplementation of the UNIX operating system, it is a good idea to look at the philosophy that made UNIX widely loved. Doug McIlroy summarized the UNIX philosophy in three simple rules:

Odds are that you do not intend to write programs for GNU/Linux. However, even as a user these basic UNIX rules can mean a lot to you. Once you get to know the essential commands that have been part of UNIX for many years, you will be able to combine simple programs to solve complex problems. Keep this in mind while you learn Slackware Linux; try to get a feeling for how you can divide complex tasks in simple combined operations.

Most packages in Slackware Linux are published under a free software or open source license. Under these licenses software may be used, studied, changed and distributed freely. Practically, this means that the software is available and redistributable in source and binary form. Although the free software and open source software movements share many licenses and principles, there are subtle differences between both movements. The open source movement tends to focus on the economic and technical advantages of sharing source code, while the free software movement puts accent on the ethical side of providing sources and binaries freely. As the GNU website puts it: “Free software is a matter of liberty, not price. To understand the concept, you should think of free as in free speech, not as in free beer.^[1]” In the spirit of free and open source software the source code of almost all packages is included in the official Slackware Linux CD set or DVD.

Slackware Linux is freely downloadable from the official Slackware Linux mirrors. The list of Slackware mirrors is available at http://www.slackware.com/getslack/.

You can also order Slackware Linux as a CD set or DVD from the Slackware Store. Many Internet shops also provide Slackware Linux cheaply on CD-ROM or DVD, but you are only supporting Slackware Linux financially if you buy an official CD set or DVD. The Slackware Store also offers Slackware Linux subscriptions. A subscriber automatically receives new Slackware Linux releases at a reduced price.

If you would like to have more information about purchasing Slackware Linux, visit the Slackware Store website at http://store.slackware.com/.

There are many websites and forums related to GNU/Linux and Slackware Linux on the Internet. But many sites often disappear as fast as they appeared, and the information on many web sites is fragmentary. The following resources have been around for a longer time, and provide good content.

The easiest method for booting the installation system is by using the installation CD-ROM. The Slackware Linux installation CD-ROM is a bootable CD, which means that the BIOS can boot the CD, just like it can boot, for example, a floppy disk. Most modern systems have a BIOS which supports CD-ROM booting.

If the CD is not booted when you have the CD inserted in the CD-ROM drive during the system boot, the boot sequence is probably not correctly configured in the BIOS. Enter the BIOS setup (usually this can be done by holding the <Del> or <Esc> key when the BIOS screen appears) and make sure the CD-ROM is on the top of the list in the boot sequence. If you are using a SCSI CD-ROM you may have to set the boot sequence in the SCSI BIOS instead of the system BIOS. Consult the SCSI card manual for more information.

When the CD-ROM is booted, a pre-boot screen will appear. Normally you can just press <ENTER> to proceed loading the default (hugesmp.s) Linux kernel. This kernel requires at least a Pentium Pro CPU. You can boot an alternative kernel by entering the kernel name on the prompt, and pressing <ENTER>. The following table lists the different kernels that are available from the Slackware Linux CD or DVD.

After booting the installation system, you will be asked whether you are using a special (national) keyboard layout or not. If you have a normal US/International keyboard, which is the most common, you can just press <Enter> at this question. After that the login prompt will appear. Log on as “root”, no password will be requested. After login, the shell is started and you can begin installing Slackware Linux. The installation procedure will be explained briefly in this chapter.

Installing Slackware Linux requires at least one Linux partition, creating a swap partition is also recommended. To be able to create a partition there has to be free unpartitioned space on the disk. There are some programs that can resize partitions. For example, FIPS can resize FAT partitions. Commercial programs like Partition Magic can also resize other partition types.

After booting the Slackware Linux CD-ROM and logging on, there are two partitioning programs at your disposal: fdisk and cfdisk. cfdisk is the easiest of both, because it is controlled by a menu interface. This section describes the cfdisk program.

To partition the first harddisk you can simply execute cfdisk. If you want to partition another disk or a SCSI disk you have to specify which disk you want to partition (cfdisk /dev/device). ATA hard disks have the following device naming: /dev/hdn, with “n” replaced by a character. E.g. the “primary master” is named /dev/hda, the “secondary slave” is named /dev/hdd. SCSI disks are named in the following way: /dev/sdn, with “n” replaced by the device character (the first SCSI disk = a, the fourth SCSI disk = d).

Figure 5.1. The cfdisk parition tool

After starting cfdisk, the currently existing partitions are shown, as well as the amount of free space. The list of partitions can be navigated with the “up” and “down” arrow keys. At the bottom of the screen some commands are displayed, which can be browsed with the “left” and “right” arrow keys. A command can be executed with the <Enter> key.

You can create a Linux partition by selecting “Free Space” and executing the “New” command. cfdisk will ask you whether you want to create a primary or logical partition. The number of primary partitions is limited to four. Linux can be installed on both primary and logical partitions. If you want to install other operating systems besides Slackware Linux that require primary partitions, it is a good idea to install Slackware Linux onto a logical partition. The type of the new partition is automatically set to “Linux Native”, so it is not necessary to set the partition type.

The creation of a swap partition involves the same steps as a normal Linux partition, but the type of the partition has to be changed to “Linux Swap” after the partition is created. The suggested size of the swap partition depends on your own needs. The swap partition is used to store programs if the main (RAM) memory is full. If you have a harddisk of a reasonable size, it is a good idea to make a 256MB or 512MB swap partition, which should be enough for normal usage. After creating the partition, the partition type can be changed to “Linux Swap” by selecting the “Type” command. The cfdisk program will ask for the type number. “Linux Swap” partitions have type number 82. Normally number 82 is already selected, so you can go ahead by pressing the <Enter> key.

If you are satisfied with the partitioning you can save the changes by executing the “Write” command. This operation has to be confirmed by entering yes. After saving the changes you can quite cfdisk with the Quit command. It is a good idea to reboot the computer before starting the installation, to make sure that the partitioning changes are active. Press <ctrl> + <alt> + <del> to shut Linux down and restart the computer.

The Slackware Linux installer is started by executing setup in the installation disk shell. Setup will show a menu with several choices. You can see a screenshot of the installer in Figure 5.2, “The setup tool”. Every option is required for a complete Slackware Linux installation, but once you start, the setup program will guide you through the options.

Figure 5.2. The setup tool

The first part of the installation is named “ADDSWAP”. The setup tool will look for a partition with the “Linux Swap” type, and ask you if you want to format and activate the swap partition (see figure Figure 5.3, “Setting up the swap partition”). Normally you can just answer “Yes”.

Figure 5.3. Setting up the swap partition

After setting up the swap space the “TARGET” menu is launched, which you can see in Figure 5.4, “Selecting a partition to initialize”. It is used to initialize the Slackware Linux partitions. Setup will display all partitions with the “Linux Native” type.

Figure 5.4. Selecting a partition to initialize

After selecting one partition, the setup tool will ask whether you want to format a partition or not, and if you want to format it, whether you want to check the disk for bad sectors or not (Figure 5.5, “Formatting the partition”). Checking the disk can take a lot of time.

Figure 5.5. Formatting the partition

After selecting to format a partition, you can specify which filesystem should be used (Figure 5.6, “Selecting a filesystem type”). Normally you can choose the ext2, ext3 and reiserfs filesystems. Ext2 was the standard Linux filesystem for many years, but it does not support journaling. A journal is a special file or area of a partition in which all filesystem operations are logged. When the system crashes, the filesystem can be repaired rapidly, because the kernel can use the log to see what disk operations were performed. Ext3 is the same filesystem as Ext2, but adds journaling. Reiserfs is a filesystem that also provides journaling. Reiserfs uses balanced trees, which make many filesystem operations faster than with Ext2 or Ext3, especially when working with many small files. A disadvantage is that Reiserfs is newer, and can be a bit more unstable.

Figure 5.6. Selecting a filesystem type

The first initialized partition is automatically mounted as the root (/) partition. For other partitions the mount point can be selected after the initialization. You could, for example, make separate partitions for /, /var, /tmp, /home and /usr. This provides extra protection against crashes. Since / is rarely changed after the installation if you create these partitions, the chance that it will be in the middle of a write operation during a crash is much smaller. Besides that, it is safer to create a separate filesystem for /home. If a program has a security vulnerability, a user could create a hard link to the binary of that program, if the /home directory is on the same filesystem as the /{s}bin /usr/{s}bin, or /usr/local/{s}bin directories. This user will then still be able to access the old, vulnerable binary after the program is upgraded.

The next step is to select the source medium (Figure 5.7, “Selecting the source medium”). This dialog offers several choices, like installing Slackware Linux from a CD-ROM or installing Slackware Linux via NFS. Slackware Linux is usually installed from CD-ROM, so this is what we are going to look at. After selecting “CD-ROM” you will be asked whether you want to let setup look for the CD-ROM itself (“Auto”) or you want to select the CD-ROM device yourself (“Manual”). If you select “Manual” the setup tool will show a list of devices. Select the device holding the Slackware Linux CD-ROM.

Figure 5.7. Selecting the source medium

After choosing an installation source the setup tool will ask you which disk sets (series) you want to install packages from (Figure 5.8, “Selecting the disk sets”). A short description of each disk set is listed.

Figure 5.8. Selecting the disk sets

Now it is almost time to start the real installation. The next screen asks how you would like to install. The most obvious choices are “full”, “menu” or “expert”. Selecting “full” will install all packages in the selected disk sets. This is the easiest way of installing Slackware Linux. The disadvantage of this choice is that it can take quite much disk space. The “menu” option will ask you for each disk set which packages you want to install. The “expert” option is almost equal to the “menu” option, but allows you to deselect some very important packages from the “a” disk set.

After the completion of the installation the setup tool will allow you to configure some parts of the system. The first dialog will ask you where you would like to install the kernel from (see Figure 5.9, “Installing the kernel”). Normally it is a good idea to install the kernel from the Slackware Linux CD-ROM, this will select the kernel you installed Slackware Linux with. You can confirm this, or select another kernel.

Figure 5.9. Installing the kernel

At this point you can choose to make a bootdisk (Figure 5.10, “Creating a bootdisk”). It is a good idea to make a bootdisk, you can use it to boot Slackware Linux if the LILO configuration is botched.

Figure 5.10. Creating a bootdisk

The following dialog can be used to make a link, /dev/modem, that points to your modem device. (Figure 5.11, “Selecting the default modem”). If you do not have a modem you can select no modem.

Figure 5.11. Selecting the default modem

The next step is to select whether you would like to use hotplug (Figure 5.12, “Enabling hotplugging”). Hotplug is used for automatically configuring pluggable USB, PCMCIA and PCI devices. Generally speaking, it is a good idea to enable hotplugging, but some systems may have problems with the probing of the hotplug scripts.

Figure 5.12. Enabling hotplugging

The following steps are important, the next dialogs will assist you with installing LILO, the Linux bootloader. Unless you have experience in configuring LILO it is a good idea to choose to use the simple option for configuration of LILO, which tries to configure LILO automatically (Figure 5.13, “Selecting the kind of LILO installation”).

Figure 5.13. Selecting the kind of LILO installation

After selecting the simple option the LILO configuration utility will asks you whether you would like to use a framebuffer or not (Figure 5.14, “Choosing the framebuffer resolution”). Using a framebuffer will allow you to use the console in several resolutions, with other dimensions than the usual 80x25 characters. Some people who use the console extensively prefer to use a framebuffer, which allows them to keep more text on the screen. If you do not want a framebuffer console, or if you are not sure, you can choose standard here.

Figure 5.14. Choosing the framebuffer resolution

After setting the framebuffer you can pass extra parameters to the kernel (Figure 5.15, “Adding kernel parameters”). This is normally not necessary, if you do not want to pass extra parameters you can just press the <Enter> key.

Figure 5.15. Adding kernel parameters

The last step of the LILO configuration is selecting where LILO should be installed (Figure 5.16, “Choosing where LILO should be installed”). MBR is the master boot record, the main boot record of PCs. Use this option if you want use Slackware Linux as the only OS, or if you want to use LILO to boot other operating systems. The Root option will install LILO in the boot record of the Slackware Linux / partition. Use this option if you use another bootloader.

Figure 5.16. Choosing where LILO should be installed

You will now be asked to configure your mouse. Select the mouse type from the dialog that appears (Figure 5.17, “Configuring a mouse”).

Figure 5.17. Configuring a mouse

You will then be asked whether the gpm program should be loaded at boot time or not (Figure 5.18, “Choosing whether GPM should be started or not”). gpm is a daemon that allows you to cut and paste text on the console.

Figure 5.18. Choosing whether GPM should be started or not

The next few steps will configure network connectivity. This is required on almost every networked system. The Slackware Linux setup will ask you if you want to set up network connectivity (Figure 5.19, “Choosing whether you would like to configure network connectivity”). If you answer “No” you can skip the next few network-related steps.

Figure 5.19. Choosing whether you would like to configure network connectivity

You will now be asked to set the hostname (Figure 5.20, “Setting the host name”). Please note that this is not the fully qualified domain name (FQDN), just the part that represents the host (normally the characters before the first dot in a FQDN).

Figure 5.20. Setting the host name

After setting the host name you can set the domain name part of the fully qualified domain name (FQDN) (Figure 5.21, “Setting the domain name”).

Figure 5.21. Setting the domain name

The rest of the network configuration steps depend on whether nodes in the network are configured to use a static or a dynamic IP address. Some networks have a DHCP server that automatically assigns an IP address to hosts in the network. If this is the case for the network the machine select DHCP during this step of the installation (Figure 5.22, “Manual or automatic IP address configuration”). When DHCP is selected you will only be asked whether a host name should be sent to the server. Normally you can leave this blank. If you use DHCP you can skip the rest of the network configuration described below.

If the network does not have a DHCP server you can choose the static IP option, which will allow you to set the IP address and related settings manually.

Figure 5.22. Manual or automatic IP address configuration

The first step of the manual configuration is to set the IP address of the first interface (eth0) of the machine (Figure 5.23, “Setting the IP addres”).

Figure 5.23. Setting the IP addres

After setting the IP address you will be asked to enter the netmask. The netmask is usually dependent on the IP address class (Figure 5.24, “Setting the netmask”).

Figure 5.24. Setting the netmask

You will then be asked to set the address of the gateway (Figure 5.25, “Setting the gateway”). The gateway is the machine on the network that provides access to other networks by routing IP packets. If your network has no gateway you can just hit the <ENTER> key.

Figure 5.25. Setting the gateway

The next dialog will ask you whether you want to use a nameserver or not (Figure 5.26, “Choosing whether you want to use a nameserver or not”). A nameserver is a server that can provide the IP address for a hostname. For example, if you surf to www.slackbasics.org, the nameserver will “convert” the www.slackbasics.org name to the corresponding IP address.

Figure 5.26. Choosing whether you want to use a nameserver or not

If you chose to use a nameserver, you will be given the opportunity to set the IP address of the nameserver (Figure 5.27, “Setting the nameserver(s)”).

Figure 5.27. Setting the nameserver(s)

The final network settings screen provides an overview of the settings, giving you the opportunity to correct settings that have errors (Figure 5.28, “Confirming the network settings”).

Figure 5.28. Confirming the network settings

After the network configuration you can set which services should be started (Figure 5.29, “Enabling/disabling startup services”). You can mark/unmark services with the <SPACE> key.

Figure 5.29. Enabling/disabling startup services

Traditionally the system clock is set to the UTC timezone on UNIX(-like) systems. If this is the case, select Yes during the next step (Figure 5.30, “Choosing whether the clock is set to UTC”). If you also use a non-UNIX(-like) OS on the same system, like Windows, it is usually a good idea to choose No, because some PC operating systems do not work with a separate system clock and software clock.

Figure 5.30. Choosing whether the clock is set to UTC

You will then be given the opportunity to select the time zone (Figure 5.31, “Setting the timezone”). This is especially important on systems that have their system clock set to UTC, without selecting the correct timezone the software clock will not match the local time.

Figure 5.31. Setting the timezone

If you installed the X Window System you can now set the default window manager (Figure 5.32, “Choosing the default window manager”). The most basic functionality of a window manager is to provide basic window managing functionality like title bars. But some options, like KDE, provide a complete desktop environment.

Figure 5.32. Choosing the default window manager

The final step is to set the root password (Figure 5.33, “Setting the root password”). The setup will ask you whether you would like to set it or not. There is no reason not to do this, and without a root password your system is dangerously insecure.

Figure 5.33. Setting the root password

At this point you have completed the Slackware Linux installation. You can now reboot the system to start your fresh new Slackware Linux system. It wasn't that hard, was it? ;-)

Figure 5.34. Finished

If you have performed a normal installation, you should not have any problems partitioning a disk. You can use the fdisk and cfdisk commands to partition disks. If you are scripting the installation of Slackware Linux it is useful to know that you can pipe fdisk commands to fdisk. For example:

# fdisk /dev/hda << EOF
n
p
1

+10000M
n
p
2

+512M
t
2
82
w
EOF
    

These commands create a primary Linux partition of 10000MB, and a primary Linux swap partition of 512MB. You could store the fdisk commands in different disk profiles, and use one of the profiles based on the specific deployment (e.g. the disk size). For example:

# cat /usr/share/fdisk-profiles/smalldisk | fdisk
    

After making at least a swap and a Linux partition, you can initialize the filesystem and swap space and make use of this storage. On systems that are short on memory, you should initialize, and use swap first. We will use the partition layout used in the partitioning example listed above in the following examples. To set up and use swap, execute:

# mkswap /dev/hda2
# swapon /dev/hda2
    

The meaning of these commands is quite obvious. mkswap initializes the swap space, and swapon puts it to use. You will only have to execute mkswap once, but swapon has to be executed during every system boot. This can be done automatically by adding an entry for the swap partition to /etc/fstab, which we will do during a later step.

For now, it is important to initialize the target partitions. This can be done with the mkfs command. You can specify which filesystem should be used by adding the -t parameter. mkfs will automatically invoke a mkfs.filesystem command based on the filesystem that you have chosen. Be aware that the filesystems that can be used depends on the installation kernel that you have booted. If you have booted the bare.i kernel, you can use the ext2, ext3 and reiserfs filesystems.

To initialize an ext3 filesystem, and mount it, you should execute the following commands:

# mkfs -t ext3 /dev/hda1
# mount /dev/hda1 /mnt
    

If you have made separate partitions for certain directories in the root filesystem, e.g. /home, you can also initialize them and mount them at this point. For example:

# mkfs -t ext3 /dev/hda2
# mkdir /mnt/home
# mount /dev/hda2 /mnt/home
    

Finally, you will have to mount your source medium. If you use a CD-ROM, this is easy. Suppose that /dev/hdc is the CD-ROM device file, you can mount the CD-ROM with:

# mount /dev/hdc /var/log/mount
    

Using NFS as the installation medium requires some more steps. First of all, you will have to load the network disk. You can do this by running the network command and inserting a network disk. You can also load this disk from another medium, for example from an USB memory stick. Suppose that you have mounted a USB memory stick on /var/log/mount, you can load the network disk with: network /var/log/mount/network.dsk. After loading the network disk, you will have to configure the network interface. If the NFS server is on the same network, you will only have to assign an IP address to the network interface. For example, to use the address 192.168.2.201, you could execute the following command:

# ifconfig eth0 192.168.2.201
    

You can then load the portmapper, which is necessary for the NFS client to function correctly:

# /sbin/rpc.portmap
    

If the portmapper started correctly, you can mount the NFS volume. But, first make sure that you unmount any filesystem that you have previously mounted at /var/log/mount. If no other filesystems are mounted at /var/log/mount, you can proceed with mounting the NFS volume. Suppose, that you want to mount 192.168.2.1:/home/pub/slackware-current, you should issue the following command:

# mount -r -t nfs -o nolock 192.168.2.1:/home/pub/slackware-current /var/log/mount
    

If no errors where printed when the volume was mounted, it should be accessible through /var/log/mount

Everything is now set up to start installing packages from the installation medium. Since installpkg is available from the installation system, you can use it to install Slackware Linux packages. To install packages to the target partition(s) mounted on /mnt, add the -root option. The following command installs all packages from the source medium:

# installpkg -root /mnt /var/log/mount/slackware/*/*.tgz
    

If you have created tagfiles to define which packages should be installed, then you can use them now (tagfiles are described in Section 17.4, “Tagfiles”). Suppose that you have stored a tagfile for each disk set in /usr/share/tagfiles/small-desktop, you can install packages based on the tagfiles in the following manner:

# for p in a ap d e f k kde kdei l n t tcl x xap y; do
   installpkg -infobox -root /mnt \
     -tagfile /usr/share/tagfiles/small-desktop/$p/tagfile \
     /var/log/mount/slackware/$p/*.tgz
done
    

The next sections describe the bare minimum of configuration that is necessary to get a running system.

#  cat > /mnt/etc/fstab << EOF
/dev/hda2	 swap             swap        defaults         0   0
/dev/hda1        /                ext3        defaults         1   1
devpts           /dev/pts         devpts      gid=5,mode=620   0   0
proc             /proc            proc        defaults         0   0
EOF
      

# cat > /mnt/etc/lilo.conf << EOF
boot = /dev/hda
vga = normal
timeout = 50
image = /boot/vmlinuz
	root = /dev/hda1
	label = Slackware
	read-only
EOF
      

# lilo -r /mnt
      

# cat > /mnt/etc/networks << EOF
loopback        127.0.0.0
localnet        127.0.0.0
EOF
      

# cat > /mnt/etc/HOSTNAME << EOF
sugaree.example.net
EOF