LPI Linux Certification/LPIC2 Exam 201/Filesystems

Section Overview

Operating the Linux filesystem
Maintaining a Linux filesystem
Creating and configuring filesystem options

Operating the Linux filesystem

Overview

Description: Candidates should be able to properly configure and navigate the standard Linux filesystem. This objective includes configuring and mounting various filesystem types. Also included, is manipulating filesystems to adjust for disk space requirements or device additions.

Key files, terms, and utilities include:

/etc/fstab
/etc/mtab
/proc/mounts
mount and umount
sync
swapon
swapoff

Mounting and unmounting partition

To access an existing partition you need to mount it first using the mount command.
For example if you want to mount a ntfs partition on /mnt/windows you should issue the following command:

mount -t ntfs /dev/hda3 /mnt/windows

Of course you need to change hda3 with your ntfs partition.
To umount a partition you simply need to use umount

umount /mnt/windows

or

umount /dev/hda3

If you use mount without arguments it will print the currently mounted devices, you can also see /proc/mounts and /etc/mtab to discover which partition are currently mounted.

Fstab

If you want to use a more automatic method to mount filesystem you should edit /etc/fstab

<file system> <mount point>   <type>  <options>       <dump>  <pass>
proc            /proc           proc    defaults        0       0
/dev/hda2       /               ext3    defaults        0       1
/dev/hda4       none            swap    defaults        0       0
/dev/hda1       /boot           ext3    defaults        0       2
/dev/hda3       /mnt/windows    ntfs    defaults        0       0
/dev/hdb        /media/cdrom    iso9660 ro,user,noauto  0       0
/dev/fd0        /media/floppy   auto    user,noauto     0       0

In the above example of /etc/fstab we have the ntfs partition mounted automatically during the system boot on /mnt/windows, while on the cdrom and floppy devices we have specified the noauto and user options, this means that they aren't mounted during boot but also that any user can mount it whenever they need. The sixth field should be 1 for root filesystem and 2 for other fs that need to be checked with fsck during boot.

Swap

The swap partition can be used as virtual memory, to create a swap partition you should use mkswap

mkswap /dev/hda4

and need to be activated with swapon

swapon /dev/hda4

you can also deactivate it with swapoff

swapoff /dev/hda4

Sync

The sync utility can be used to force the change onto the partition, modern filesystem like ext3 or reiserfs sync the partition every time that a change is made so you don't need to issue the command manually.

=== Exercises ===.

Maintaining a Linux filesystem

Overview

Description: Candidates should be able to properly maintain a Linux filesystem using system utilities. This objective includes manipulating a standard ext2 filesystem.

Key files, terms, and utilities include:

fsck (fsck.ext2)
badblocks
mke2fs
dumpe2fs
debuge2fs
tune2fs

Formatting a partition

Before you format a partition you need to choose the right filesystem for your needs. The most common filesystem on linux is ext3 which is a journaled filesystem based on ext2. To format a partition with a filesystem you need to use the mkfs.* commands

 #ext3
 mkfs.ext3 /dev/hda1
 #fat
 mkfs.vfat /dev/hda1
 #xfs 
 mkfs.xfs /dev/hda1
 #reiserfs
 mkfs.reiserfs /dev/hda1

to create an ext2/ext3 filesystem you can also use the mke2fs utility

#ext2
mke2fs /dev/hda1
#ext3
mke2fs -j /dev/hda1

Configuring and repair filesystem

tune2fs it's an utility used to tune ext2/ext3 filesystem

#add the journal to an ext2 filesystem(convert from ext2 to ext3)
tune2fs -j /dev/hda1
#set the max mount count before the filesystem is checked for errors to 30
tune2fs -c 30 /dev/hda1 
#set the max time before the filesystem is checked for errors to 10 days
tune2fs -i 10d /dev/hda1

you can also tune a reiserfs partition using reiserfstune

#create a new journal for /dev/hda1 into /dev/hda2 
reiserfstune --journal-new-device /dev/hda2 -f /dev/hda1

to check a filesystem for errors you can use fsck.*

 #ext3
 fsck.ext3 /dev/hda1
 #fat
 fsck.vfat /dev/hda1
 #xfs 
 fsck.xfs /dev/hda1
 #reiserfs
 fsck.reiserfs /dev/hda1

you can also just run fsck /dev/hda1 directly and it will detect the filesystem

=== Exercises ===.

Creating and configuring filesystem options

Overview

Description: Candidates should be able to configure automount filesystems. This objective includes configuring automount for network and device filesystems. Also included is creating non ext2 filesystems for devices such as CD-ROMs.

Key files, terms, and utilities include:

/etc/auto.master
/etc/auto.[dir]
mkisofs
dd
mke2fs