3.5. Förpartionering för system med flera operativsystem

Partitionering av din disk refererar helt enkelt till processen att dela upp din disk i sektioner. Varje sektion blir då oberoende av de andra. Det är grovt sett likvärdigt med att sätta upp väggar inne i ett hus; om du ställer in möbler i ett rum så påverkar de inte något annat rum.

If you already have an operating system on your system which uses the whole disk and you want to stick Debian on the same disk, you will need to repartition it. Debian requires its own hard disk partitions. It cannot be installed on Windows or Mac OS X partitions. It may be able to share some partitions with other Unix systems, but that's not covered here. At the very least you will need a dedicated partition for the Debian root filesystem.

You can find information about your current partition setup by using a partitioning tool for your current operating system, such as Disk Utility, Drive Setup, HD Toolkit, or MacTools. Partitioning tools always provide a way to show existing partitions without making changes.

Normalt sett så kommer data och filer i ett filsystem på en partition att förstöras om partitionen ändras. Därför bör du alltid göra säkerhetskopior innan du partitionerar om. Om man använder jämförelsen med huset skulle du antagligen vilja flytta ut alla möbler innan väggarna flyttas då de annars riskerar att de förstörs.

Several modern operating systems offer the ability to move and resize certain existing partitions without destroying their contents. This allows making space for additional partitions without losing existing data. Even though this works quite well in most cases, making changes to the partitioning of a disk is an inherently dangerous action and should only be done after having made a full backup of all data.

Creating and deleting partitions can be done from within debian-installer as well as from an existing operating system. As a rule of thumb, partitions should be created by the system for which they are to be used, i.e. partitions to be used by Debian GNU/Linux should be created from within debian-installer and partitions to be used from another operating system should be created from there. debian-installer is capable of creating non-Linux partitions, and partitions created this way usually work without problems when used in other operating systems, but there are a few rare corner cases in which this could cause problems, so if you want to be sure, use the native partitioning tools to create partitions for use by other operating systems.

If you are going to install more than one operating system on the same machine, you should install all other system(s) before proceeding with the Debian installation. Windows and other OS installations may destroy your ability to start Debian, or encourage you to reformat non-native partitions.

Du kan oftast reparera eventuella fel som uppstår efter de här åtgärderna eller undvika att felen uppstår, men att installera det ursprungliga systemet först besparar dig troligen en hel del problem.

In order for OpenFirmware to automatically boot Debian GNU/Linux the Linux partitions should appear before all other partitions on the disk, especially Mac OS X boot partitions. This should be kept in mind when pre-partitioning; you should create a Linux placeholder partition to come before the other bootable partitions on the disk. (The small partitions dedicated to Apple disk drivers are not bootable.) You can delete the placeholder with the Debian partition tools later during the actual install, and replace it with Linux partitions.

3.5.1. Mac OS X Partitioning

The Disk Utility application can be found under the Utilities menu in Mac OS X Installer. It will not adjust existing partitions; it is limited to partitioning the entire disk at once.

Kom ihåg att skapa en tom partition för GNU/Linux, helst placerad först i disklayouten. Det spelar ingen roll vilken typ det är, den kommer att tas bort och ersättas senare av Debian GNU/Linuxs installationsprogram.

Debian installer partition table editing tools are compatible with OS X, but not with MacOS 9. If you are planning to use both MacOS 9 and OS X, it is best to install OS X and Debian on one hard drive, and put MacOS 9 on a separate hard drive. Separate options for OS 9 and OS X will appear when holding the option key at boot time, and separate options can be installed in the yaboot boot menu as well.

GNU/Linux is unable to access information on UFS partitions, but can access HFS+ (aka MacOS Extended) partitions. OS X requires one of these two types for its boot partition. MacOS 9 can be installed on either HFS (aka MacOS Standard) or HFS+. To share information between the Mac OS X and GNU/Linux systems, an exchange partition is handy. HFS, HFS+ and MS-DOS FAT file systems are supported by MacOS 9, Mac OS X and GNU/Linux.