Tài liệu Installation docx

3 Installation CERTIFICATION OBJECTIVES 3.01 Selecting an Installation Option 3.02 Required Disk Space 3.03 Filesystems 3.04 The Installation Process 3.05 Boot Loaders: GRUB and LILO 3.06 Creating Partitions: Details 3.07 Other Installation Sources 3.08 Viewing Boot Time Information 3.09 Postinstallation Validation 3.10 Sample Installation Exercises ✓ Two-Minute Drill Q&A Self Test CertPrs8 / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 Blind Folio 3:95 CertPrs8 / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 Blind Folio 3:95 D:\omh\CertPrs8\485-1\ch03.vp Wednesday, September 18, 2002 9:48:05 AM Color profile: Generic CMYK printer profile Composite Default screen I nstallation is one of the three parts of the RHCE exam. To pass this part of the exam, you’ll need to know a lot more than just the basic GUI installation process for a single computer! Once you’ve studied the installation chapters (2, 3, and 5), you’ll be able to install Red Hat Linux in a number of ways: directly from the CD, using boot disks, managing special situations on laptop computers, accessing from networks, and using automated Kickstart-based tools. While this chapter covers the “basics,” the basics are important. You’ll learn the nuances of different installation classes. Both fdisk and Disk Druid are useful tools for configuring your hard drives. Both GRUB and LILO are popular and flexible options as boot loaders. And if you’re managing a LAN and don’t want to spend all night inserting CDs and typing in commands at every computer, you need to learn how to install Red Hat Linux in various network configurations. Many users download their version of Red Hat Linux directly from one of many FTP sites on the Internet. That is a common practice in a software world governed by the Linux General Public License. There are four basic installation routes that you can take—but they all use the same packages, and customization is possible in each case. All you need to get started is sufficient unformatted free disk space. The easiest way to get this is by adding a new disk drive to your system. The mechanics of adding a drive and changing your CMOS settings (so your CD-ROM is a bootable device) are beyond the scope of this book, but neither operation is complicated. Once the new drive is installed and your system is configured to boot from the CD-ROM drive, just stick the first Red Hat Installation CD-ROM into the CD drive and reboot! Take the defaults for a Workstation installation and see what happens; it will probably just install, dual-boot automatically, and voilà! You are ready to play! As you prepare for the RHCE exam, remember to think in terms of what is practical. While it is important to know how to download and set up a Red Hat Installation CD, it wouldn’t be practical for a group of students to all be downloading the Red Hat installation CDs during an actual exam. 96 Chapter 3: Installation CertPrs8 / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 D:\omh\CertPrs8\485-1\ch03.vp Wednesday, September 18, 2002 9:48:06 AM Color profile: Generic CMYK printer profile Composite Default screen CERTIFICATION OBJECTIVE 3.01 Selecting an Installation Option Red Hat Linux includes its own installation program. The graphical version of this program is known as Anaconda. There are five basic directions you can take during the installation process: Personal Desktop, Workstation, Server, Custom, and Upgrade. This section will help you understand the implications of each of these choices, as illustrated in Figure 3-1. Time is usually of the essence on the RHCE exam. As text mode installation is the fastest way to install Red Hat Linux, all of the Figures in this chapter are based on that installation method. The two most important options are Workstation and Server. Almost by definition, a Workstation installation is much simpler than a Server installation. Furthermore, Workstation installs are optimized for local user applications associated with the X Window system. While many Linux administrators don’t even bother installing the X Window on a Linux server, expect to install the X Window for regular users. Selecting an Installation Option 97 CertPrs8 / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 FIGURE 3-1 Red Hat installation options D:\omh\CertPrs8\485-1\ch03.vp Wednesday, September 18, 2002 9:48:06 AM Color profile: Generic CMYK printer profile Composite Default screen It’s important for administrators to know how to configure the X Window on a Linux computer. The server installation includes more network servers and management features. The default Red Hat Linux server includes several distinct partitions that make up the filesystem, including separate /usr, /home, and /var directories. By splitting out the /home directories to one partition, disk quotas can be maintained on just that filesystem, and backups and restores are more specific. With smaller filesystems, it is easier to recover from a disaster. In addition, it is easier to expand a smaller filesystem. Depending on your needs, you can set up a system with anywhere from 500MB to 4.7GB of files. Of course, you have to have additional room for user files, log files, and any additional applications that you may want to install in the future. The essence of each installation is in the installed packages. As you examine each of the options, focus on the installed packages. Several partitions are associated with specific sizes. For example, the current default size for /boot is 100 MB. The actual size that you see in your installation will vary depending on the size and number of cylinders on your hard drive(s). Personal Desktop The Personal Desktop option includes packages for basic Linux users. Generally, more experienced users like yourself will use the Workstation or Server installation options. The following lists the minimum disk space requirements for a basic US Personal Desktop installation. ■ Personal Desktop with GNOME or KDE: 1.8GB ■ Personal Desktop with GNOME and KDE: 1.9GB Please note, these figures may vary slightly from those shown in the Red Hat Linux documentation. They were taken from a sample installation of the latest Red Hat Linux beta available at the time of this writing. This is just the minimum disk space required for Linux packages and other files. You’ll also need a swap partition. In the default configuration, Red Hat Linux sets up a swap partition that is twice the size of the detected RAM. You’ll also require more for actual data files such as documents, downloads, source files, and more. If you’ve set up additional partitions for separate directories such as /home, /usr, and /tmp, the space requirements will also increase. 98 Chapter 3: Installation CertPrs8 / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 D:\omh\CertPrs8\485-1\ch03.vp Wednesday, September 18, 2002 9:48:06 AM Color profile: Generic CMYK printer profile Composite Default screen If you are testing Linux for the first time, add at least several hundred megabytes of additional space; more if you plan to reconfigure your kernel. With other applications available during Red Hat Linux installation, you may need 4GB or more of disk space. Behind the Scenes: The Partition Layout for Personal Desktop The Personal Desktop installation option first deletes all Linux partitions. Other partitions, such as those created for Microsoft Windows filesystems such as VFAT and NTFS, are untouched. The deleted Linux partitions are added to the free space on your hard drive. Then the default Workstation installation configures the following three partitions in that free space: ■ A swap partition twice the size of your RAM. (This may change if the amount of RAM is large or the size of your hard drive is small.) ■ A 100MB /boot partition. ■ A variable-sized partition for the root directory, configured to consume all remaining free space. As of Red Hat 8.0, there is no longer a separate installation option for laptop computers. Dual-Boot with Previous OS Any previous operating system that existed on the machine is left intact. This provides several advantages. It is appropriate on a test or development computer where you need both operating systems. Alternatively, if you’re making the transition to Linux, you may still need the old operating system for a few files and applications. Please note, the figures for required hard disk space may vary from those shown in the Red Hat Linux documentation. They were taken from a sample installation of the latest Red Hat Linux beta available at the time of this writing. Workstation The following lists the minimum recommended disk space requirements for a basic workstation installation. ■ Workstation with GNOME or KDE: 2.1GB ■ Workstation with GNOME and KDE: 2.3GB Selecting an Installation Option 99 CertPrs8 / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 D:\omh\CertPrs8\485-1\ch03.vp Wednesday, September 18, 2002 9:48:06 AM Color profile: Generic CMYK printer profile Composite Default screen This is just the minimum disk space required for Linux packages and other files. You’ll also need a swap partition. In the default configuration, Red Hat Linux sets up a swap partition that is twice the size of the detected RAM. You’ll also require more for actual data files such as documents, downloads, source files, and more. If you are testing Linux for the first time, add at least several hundred megabytes of additional space; more if you plan to reconfigure your kernel. Behind the Scenes: The Partition Layout for Workstation The Workstation installation option first deletes all Linux partitions. Other partitions, such as those created for Microsoft Windows filesystems such as VFAT and NTFS, are untouched. The deleted Linux partitions are added to the free space on your hard drive. Then the default Workstation installation configures the following three partitions in that free space: ■ A swap partition twice the size of your RAM. (This may change if the amount of RAM is large or the size of your hard drive is small.) ■ A 100MB /boot partition ■ A variable-sized partition for the root directory, configured to consume all remaining free space The Apache Web Server package is not installed with a Workstation installation. You can add the required packages at any time using the rpm utility. Dual-Boot with Previous OS Any previous operating system that existed on the machine is left intact. This provides several advantages. It is appropriate on a test or development computer where you need both operating systems. Alternatively, if you’re making the transition to Linux, you may still need the old operating system for a few files and applications. Workstation Option Packages Installed The list of file packages installed by a default Workstation installation is listed on the CD-ROM in /RedHat/base/comps.xml. This list contains references, either directly or indirectly through the use of group names, to the hundreds of packages installed. Each package contains at least one file, and sometimes dozens or more. 100 Chapter 3: Installation CertPrs8 / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 D:\omh\CertPrs8\485-1\ch03.vp Wednesday, September 18, 2002 9:48:06 AM Color profile: Generic CMYK printer profile Composite Default screen Selecting an Installation Option 101 CertPrs8 / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 <group> <id>workstation-common</id> <uservisible>false</uservisible> <name>Workstation Common</name> <grouplist> <groupreq>base</groupreq> <groupreq>base-x</groupreq> <groupreq>admin-tools</groupreq> <groupreq>editors</groupreq> <groupreq>sound-and-video</groupreq> <groupreq>dialup</groupreq> <groupreq>office</groupreq> <groupreq>graphical-internet</groupreq> <groupreq>text-internet</groupreq> <groupreq>authoring-and-publishing</groupreq> <groupreq>printing</groupreq> <groupreq>graphics</groupreq> <groupreq>games</groupreq> </grouplist> </group> Notice that the workstation contains 13 groups (referenced by the <groupreq> container preceding the group name) of software packages. You can use this syntax to customize the installation process, if you use the automated Kickstart system discussed in Chapter 5. Server The server option includes a default group of packages that allow you to manage this computer as a Linux Server. Before starting a server installation, move any data that you might need from this computer. The server installation removes all partitions on all disks. This installation option removes all partitions on all disks. Server Partitions The default Red Hat Linux 8.0 server installation includes packages that require at least 735MB of total disk space. However, since these packages are installed in different partitions, considerable additional hard disk space is required. The default installation sets up seven different partitions: three primary, one extended, and three logical partitions, as shown in Table 3-1. D:\omh\CertPrs8\485-1\ch03.vp Wednesday, September 18, 2002 9:48:06 AM Color profile: Generic CMYK printer profile Composite Default screen The Custom Installation Option The Custom Installation option provides the most flexibility for an experienced Linux or Unix administrator. This option allows you to select all of the package groups that you need. If you know exactly what you want, you can even select from a list of individual RPM packages. Selecting Package Groups The custom installation process allows you to select as many of the package groups as you need. Each group encompasses a list of RPM packages. As explained in Chapter 4, 102 Chapter 3: Installation CertPrs8 / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 Partition Default Size / 500MB /boot 100MB /home Depends on available hard disk space /usr Depends on available hard disk space /var Depends on available hard disk space Swap Twice available RAM Extended Depends on available hard disk space TABLE 3-1 Default Red Hat Server Installation Partitions FIGURE 3-2 Red Hat Custom Installation Packages, first screen D:\omh\CertPrs8\485-1\ch03.vp Wednesday, September 18, 2002 9:48:06 AM Color profile: Generic CMYK printer profile Composite Default screen Selecting an Installation Option 103 CertPrs8 / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 some RPMs such as certain kernel libraries won’t work unless the appropriate C language compiler is installed. These are known as dependencies. The Red Hat installation program includes routines to make sure that all dependencies are satisfied. Figures 3-2 through 3-5 show the various package groups available, based on the Custom installation option. It is straightforward. Selected packages include a checkmark in the box to the left of the package group name. FIGURE 3-3 Red Hat Custom Installation Packages, second screen FIGURE 3-4 Red Hat Custom Installation Packages, third screen D:\omh\CertPrs8\485-1\ch03.vp Wednesday, September 18, 2002 9:48:07 AM Color profile: Generic CMYK printer profile Composite Default screen It’s important to pick only the package groups you need. Fewer installed packages means more room for personal files for you and your users, as well as the log files you need to monitor your system and actually get some use from your applications. See the next section for more information on each package. Understanding how these package groups work is important in a kickstart installation, which is described in more detail in Chapter 5. Packages This section includes the briefest possible overview of each of the packages you can select when you use the Custom installation option in Red Hat Linux. While the details will vary as Red Hat Linux evolves, the spirit of what is installed by these packages is relatively constant. Remember, some of these packages depend on others; for example, if you want to install Dialup Support, Red Hat will make sure that you install Network Support as well. For complete details of the RPMs associated with each package, go to the first Red Hat Linux installation CD, and read the comps.xml file in the /RedHat/base directory in the text editor or Web browser of your choice. These packages are based on the latest beta version of Red Hat Linux 8.0 available as of this writing, and are therefore subject to change. 104 Chapter 3: Installation CertPrs8 / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 FIGURE 3-5 Red Hat Custom Installation Packages, fourth screen D:\omh\CertPrs8\485-1\ch03.vp Wednesday, September 18, 2002 9:48:07 AM Color profile: Generic CMYK printer profile Composite Default screen [...]... Chapter 3 Installation FIGURE 3-7 The Startup installation screen for Red Hat Linux 8.0 Installation floppies are easy to create Depending on your hardware and location of the Red Hat installation files, select one of the following disk images: ■ boot.img Local installation from a hard disk or CD-ROM ■ bootnet.img Network installation through HTTP, FTP, or NFS ■ pcmcia.img Laptop computer–based installation. .. load is shared by the different drives Performance is improved CERTIFICATION OBJECTIVE 3.04 The Installation Process You have many interrelated questions to answer during installation, just as you have many ways to access installation files, and many options on how to install the operating system The following installation outline is designed to get you through the process in as simple a fashion as possible,... Requirements A Workstation-class installation, with GNOME or KDE (and swap space), normally takes over 2GB free space, before you add other files You can add additional packages during the Red Hat workstation-class installation process Personal Desktop-class installation requirements are nearly identical Server-Class Space Requirements The space requirements of a server-class installation can vary By default,... have to use an installation boot floppy D:\omh\CertPrs8\485-1\ch03.vp Wednesday, September 18, 2002 9:48:08 AM Color profile: Generic CMYK printer profile CertPrs8 Composite Default screen / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 The Installation Process 119 CD-ROM or Boot Diskette Starts Installation Now your PC should boot from the CD-ROM or the installation. .. Linux Study Guide / Jang / 222485-1 / Chapter 3 The Installation Process 121 FIGURE 3-13 The CD is OK Click OK and the CD should be automatically ejected You can then insert the next Red Hat installation CD for checks Once this process is complete, you can reinsert the first Red Hat installation CD and then proceed with the standard Graphical Mode installation If you want to install Red Hat Linux in... restart your computer again with the first Red Hat Linux installation CD in the drive The standard Red Hat Linux installation options are based on Figure 3-10 and 3-11: ■ Graphical Mode The default is a graphically based Red Hat installation using the program known as Anaconda ■ Text Mode The linux text option starts a low-intensity graphical installation known as text mode that all but the most graphically... described earlier ■ Non-CD Installation It’s possible to use the Installation CD to access the Red Hat Linux installation files from other sources such as over a network, with the linux askmethod option ■ Updates Red Hat hopes to have update disks available for groups of packages in the future Basic Installation Overview The basic Red Hat Linux installation is straightforward and should already be well understood... options, that of Custom installation FIGURE 3-17 Configuring a mouse D:\omh\CertPrs8\485-1\ch03.vp Wednesday, September 18, 2002 9:48:10 AM Color profile: Generic CMYK printer profile CertPrs8 Composite Default screen / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 The Installation Process 125 FIGURE 3-18 Installation options Server or Custom installations by default... Red Hat Linux Installation program provides a number of user-friendly tools for configuration The more that you can configure during the installation process, the easier your tasks are after installation is complete Color profile: Generic CMYK printer profile CertPrs8 Composite Default screen 128 Chapter 3: / RHCE Red Hat Certified Engineer Linux Study Guide / Jang / 222485-1 / Chapter 3 Installation. .. Linux before you can work though the other installation scenarios Booting the First CD-ROM Most current Intel-based PC hardware systems allow you to boot directly from the CD-ROM drive The latest official copy of Red Hat Linux, as well as Red Hat Linux installation CDs that you might download from alternate sources, is also designed to boot directly into the installation program Figure 3-7 shows the . 3 Installation CERTIFICATION OBJECTIVES 3.01 Selecting an Installation Option 3.02 Required Disk Space 3.03 Filesystems 3.04 The Installation. Partitions: Details 3.07 Other Installation Sources 3.08 Viewing Boot Time Information 3.09 Postinstallation Validation 3.10 Sample Installation Exercises ✓