Objectives

1. Objectives • Manage and install new file systems

2. Understanding the File System • During installation • Partitions created • ext3 or similar file system

3. Reviewing File System Types • File system • Collection of data structured in certain way so that it can be efficiently accessed • Superblock • Collection of information about file system as a whole • Found in ext2 and ext3

4. Reviewing File System Types • ext2 and ext3 file systems • Do not place files one after another filling up each area of hard disk in order • Permit file to grow in size without being as likely to be broken into pieces • Never need to defragment • ext3 • Journaling file system

5. Reviewing File System Types • Other journaling file systems • ReiserFS • Journaling File System (JFS) • Virtual file system model • Used by kernel • Separates file system type from operation program wants to perform • Linux can support any new file system type for which driver is available

6. Reviewing File System Types • Each file system must be mounted • Mount command • Without any parameters • List of currently mounted file systems

7. Checking File System Status • Root file system becomes full • Linux kernel can crash • df command displays space usage information for each file system that is currently mounted • If file system becomes full, must free space in directories where file system is mounted

8. Checking File System Status • Immediately free space • Look for large or numerous files in /tmp directory that can be deleted • Look for large or numerous files in /var subdirectories • Move system log file (/var/log/messages) to another file system that isn’t as full • See if any user subdirectories are using unusually large amounts of disk space • Delete unused archive files

9. Checking File System Status • du utility lists size of directory and all its subdirectories • du –max-depth=1 • Various graphical tools and system administration scripts to check status of file systems • Hardware Browser • KDiskFree - kdf

10. Checking File Systems • fsck utility • Checks integrity of file systems • Usually pronounced fizz-check • Can also repair minor file system problems • Must be run on file system that is not mounted • Example: fsck /dev/hda1

11. Creating New File Systems • Adding file system means • Adding hard disk device to your system • Making hard disk available to Linux by: • Formatting • Mounting

12. Using the fdisk Utility • Modifications to partition table only effective when you write changes to disk with w command to exit fdisk • Example: fdisk /dev/sdb

13. Using the fdisk Utility

14. Using the fdisk Utility

15. Formatting File Systems • mke2fs command • Formats partition • Erasing all information on it • Organizes space for data to be recorded • Partition can be used by Linux • Use -j option to add journaling • For ext3 • Example: mke2fs -j /dev/sdb2

16. Managing Swap Space • mkswap command • Format partition set up using fdisk as swap space • Example: mkswap /dev/hda2 • swapon command activates swap space

17. Formatting File Systems • fdformat command • Format 3.5-inch disks • gfloppy • Graphical removable disk formatter • tune2fs utility • Examine superblock of file system • Make minor changes to file system parameters

18. Mounting New File Systems • mount command • To access file system • Indicate: • Device on which file system is stored • Directory where file system should be made accessible in directory structure • Example: mount -t ext3 /dev/sdb2 /archive

19. Automating File System Mounting • /etc/fstab configuration file • Key to automounting file systems • Contains one line for each file system to automount • Add options when executing mount command • Example: mount -t ext3 -o defaults /dev/sdb2 /archive