411 REFERENCE · Wikibooks
Fedora And Red Hat System Administration/Filesystem Mangement
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Partition Management
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
Overview of Partitions
Using Radified's analogy, a partition is
like
Creating a partition
Using the fdisk utility
"fdisk -l" ---> listed
fdisk -l
the Mkfs Command
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
Inodes
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
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
ext2 and ext3
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
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
Labeling Filesystems and Block Devices
Mounting Filesystems
The mount Command
/etc/fstab
AutoFS - Automounting
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
Automounting Home Directories
AutoFS Scripts
The /net Example