Fedora And Red Hat System Administration/Filesystem Mangement

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Partition Management[edit]

A partition is a place on disk which contains


at the fdisk prompt: n - create a new partition e - create an extended partition p - will print the table

Block Devices[edit]

Overview of Partitions[edit]

Using Radified's [[1]] analogy, a partition is like

Creating a partition[edit]

Using the fdisk utility[edit]

"fdisk -l" ---> listed fdisk -l

the Mkfs Command[edit]

mkfs, then hit the tab key twice gives you a list mkfs -t * which equals mkfs.*

so mkfs.reiserfs equals mkfs -t reiserfs

VFAT filesystem - tends to be used for usb mkfs -b ----> mkfs -t every partition has

4k is what you want -> optimized for speed rat mkfs -f [fragment size] fdisk -> enters the interactive prompt w - write n - new m - manual +100m - creates a partition q - quit the command "q" will quit fdisk. if you exit with "q" rather than "w"

1000 bytes is kb 1024 bytes is a kib "kibibytes"

running the command "cat /proc/partitions" looking at the file /proc/partitions will tell you what block devices the kernel knows about partprobe - speaks to a higher level of the kernel

it is a good idea to check with "partprobe" if the kernel agrees with our partitions

Sysfs filesystem vs. Proc filesystem[edit]

Inodes[edit]

Metadata is stored in the inode

we have goto our filesystem formatted

ctime - when was the inode created mtime - when was the inode last modified

ext2 had to make sure it assigns them to the correct filesystem - tune2fs -l /dev/xvda1

dumpe2fs /dev/xvda1 holding

= Mounting the file system[edit]

if something is to show up on the desktop, then it will show up as mnt

if we "touch /home/share/unmounted"

the command to mount the

every directory has an inode for the current directory ( in the . entry)

dump e2fs will tell us if

Filesystems[edit]

ext2 and ext3[edit]

ext3 is the ext2 filesystem with journaling added. Journaling keeps track of what will be written to the disk prior to the write operation beginning. When the write is done, it is noted in the journal. If the system crashes during a write, it can recover the operation when it comes back up. This prevents incomplete writes from occurring on the disk and eliminates the need to do a filesystem check after a system crash.

jfs[edit]

JFS is a high a performance filesystem made by IBM and ported to Linux in 2001. It uses B+ trees,extents, and a journal to guarantee the consistency of the file system in the event of a crash.

reiserfs[edit]

Labeling Filesystems and Block Devices[edit]

Mounting Filesystems[edit]

The mount Command[edit]

/etc/fstab[edit]

AutoFS - Automounting[edit]

AutoFS allows the system to automatically mount devices and network shares as they are requested and even unmount them again when no longer in use. The main configuration for the automounter is /etc/auto.master. Initially, this file will only contain comments, including examples for a /etc/auto.misc and /etc/auto.net.

Basics[edit]

Automounting Home Directories[edit]

AutoFS Scripts[edit]

The /net Example[edit]