Data partitions is a generic term for partitions that are formatted as a filesystem and in which both the system and its users can store data. The partition designated as the root filesystem is a special case of a data partition because it is required in order to boot a Linux enterprise system.
The preceding sections explained how to create the swap and root partitions that must be present to successfully boot a Linux enterprise system. However, you can also create other data partitions, format them as filesystems, and specify their mount points during the installation process. On Linux enterprise systems, a mount point is simply a Linux directory through which a filesystem is made available to the system, known as mounting that filesystem. Using regular directories as mount points is a clever part of the design of Unix and Linux. If you run out of disk space on a given partition, you can add another disk to your system, create data partitions there, copy the data from existing directories to those partitions, and then mount the new partitions on the directory where the data was originally located, effectively increasing the amount of storage available to an existing system.
Today's larger disks make it attractive to create other data partitions. You have several reasons to consider creating multiple data partitions on today's disks:
- When you boot a Linux enterprise system, the system checks the consistency of each of its filesystems. Checking the consistency of a single, huge, nonjournaled filesystem can take quite a bit of time.
- Filesystem corruption can occur as a result of a number of problems, such as a system crash, sudden power loss, or hardware problems. Whenever a filesystem is corrupted, repairing it (which is mandatory) can cause you to lose data. Creating multiple partitions reduces the extent to which filesystem corruption can affect a single data partition.
- Keeping data on multiple partitions limits the chance that you can lose data during a subsequent system upgrade. Some upgrades reformat the root partition or recreate its directory structure. If your user data is stored on other data partitions, they will not be affected by changes to the root filesystem.
- Some Linux enterprise backup software backs up data on a per-partition basis. Backing up a single huge partition can take quite a bit of time. Also, if your backups fail (such as when a tape is corrupted), you may not be able to use the backups to restore your system. Creating multiple partitions limits problems related to a backup failure to a single partition.
Chapter 3 provides more detail about creating multiple partitions and the types of filesystems supported by Linux and provides additional reasons why you may want to create multiple partitions on your Linux system. Most types of Linux filesystems can be resized once they have been created, enabling you to customize your system's partitioning, even after the system has been installed and is running.
If you want to create multiple partitions during the installation process, you can do this by making sure that the root partition does not completely fill your disk and then creating additional partitions in the remaining space on your disk. Common parts of a Linux system that you may want to put on separate data partitions are /boot, /home, /opt, /tmp, /var, /usr, and /usr/local.
Customizing your SUSE Linux 10 installation
Step 1: Partitioning Your Disks
Step 2: Resizing Existing Operating Systems Partitions
Step 3: Primary and Extended Partitions
Step 4: Defining Filesystems
Step 5: The root partition
Step 6: Data Partitions
Step 7: Selecting Software for Installation
Step 8: Selecting a Boot Loader
Step 9: Changing the Default Runlevel
The above tip is excerpted from from Chapter 1, "Installing SUSE 10" our original excerpt of The SUSE Linux 10 Bible by Justin Davies, courtesy of Wiley Publishing. This chapter explains how to successfully install SUSE Linux 10 on your box. Find it helpful? Buy it on Amazon.