4.文件系统

4.6分区、格式化与挂载

4.6.4格式化

1.格式化为EXT

[root@localhost ~]# mkfs.ext4 /dev/sda3

mke2fs 1.42.9 (28-Dec-2013)

Filesystem label=

OS type: Linux

Block size=1024 (log=0)    #block大小

Fragment size=1024 (log=0)

Stride=0 blocks, Stripe width=0 blocks

51200 inodes, 204800 blocks

10240 blocks (5.00%) reserved for the super user

First data block=1

Maximum filesystem blocks=33816576

25 block groups

8192 blocks per group, 8192 fragments per group

2048 inodes per group

Superblock backups stored on blocks:

8193, 24577, 40961, 57345, 73729

Allocating group tables: done

Writing inode tables: done

Creating journal (4096 blocks): done

Writing superblocks and filesystem accounting information: done

[root@localhost ~]# dumpe2fs /dev/sda3

dumpe2fs 1.42.9 (28-Dec-2013)

Filesystem volume name:

Last mounted on:

Filesystem UUID:          3e95cd6b-7aba-4dee-bc7f-042ac125fa3d

Filesystem magic number:  0xEF53

Filesystem revision #:    1 (dynamic)

Filesystem features:      has_journal ext_attr resize_inode dir_index filetype extent 64bit flex_bg sparse_super huge_file uninit_bg dir_nlink extra_isize

Filesystem flags:         signed_directory_hash

Default mount options:    user_xattr acl

Filesystem state:         clean

Errors behavior:          Continue

Filesystem OS type:       Linux

Inode count:              51200

Block count:              204800

Reserved block count:     10240

Free blocks:              192685

Free inodes:              51189

First block:              1

Block size:               1024#block大小

Fragment size:            1024

Group descriptor size:    64

Reserved GDT blocks:      256

Blocks per group:         8192

Fragments per group:      8192

Inodes per group:         2048

Inode blocks per group:   256

Flex block group size:    16

Filesystem created:       Fri Mar 20 14:17:32 2020

Last mount time:          n/a

Last write time:          Fri Mar 20 14:17:32 2020

Mount count:              0

Maximum mount count:      -1

Last checked:             Fri Mar 20 14:17:32 2020

Check interval:           0 ()

Lifetime writes:          4449 kB

Reserved blocks uid:      0 (user root)

Reserved blocks gid:      0 (group root)

First inode:              11

Inode size:           128       #inode大小

Journal inode:            8

Default directory hash:   half_md4

Directory Hash Seed:      e0a7d3c5-f805-41e1-8e51-116851e0108f

Journal backup:           inode blocks

Journal features:         (none)

Journal size:             4096k

Journal length:           4096

Journal sequence:         0x00000001

Journal start:            0

[root@localhost ~]# mkfs.ext4 -b 4096 /dev/sda3

#block大小设定为4096

[root@localhost ~]# mkfs.ext4 -I 256 /dev/sda3

#inode大小设定为256

2.mkfs.xfs - construct an XFS filesystem

[root@localhost ~]# mkfs.xfs /dev/sda3

meta-data=/dev/sda3             isize=256    agcount=4, agsize=12800 blks

=                       sectsz=512   attr=2, projid32bit=1

=                       crc=0

data     =                       bsize=4096   blocks=51200, imaxpct=25

=                       sunit=0      swidth=0 blks

naming   =version 2              bsize=4096   ascii-ci=0 ftype=0

log      =internal log           bsize=4096   blocks=853, version=2

=                       sectsz=512   sunit=0 blks, lazy-count=1

realtime =none                   extsz=4096   blocks=0, rtextents=0

#采用默认值格式化

[root@localhost ~]# mkfs.xfs -f -i size=512 /dev/sda3

meta-data=/dev/sda3             isize=512    agcount=4, agsize=12800 blks

=                       sectsz=512   attr=2, projid32bit=1

=                       crc=0

data     =                       bsize=4096   blocks=51200, imaxpct=25

=                       sunit=0      swidth=0 blks

naming   =version 2              bsize=4096   ascii-ci=0 ftype=0

log      =internal log           bsize=4096   blocks=855, version=2

=                       sectsz=512   sunit=0 blks, lazy-count=1

realtime =none                   extsz=4096   blocks=0, rtextents=0

#指定inode大小为512，-f是强制格式化一个已经格式化过的文件系统

[root@localhost ~]# mkfs.xfs -f -b size=1024 /dev/sda3

meta-data=/dev/sda3              isize=256    agcount=4, agsize=51200 blks

=                       sectsz=512   attr=2, projid32bit=1

=                       crc=0

data     =                       bsize=1024   blocks=204800, imaxpct=25

=                       sunit=0      swidth=0 blks

naming   =version 2              bsize=4096   ascii-ci=0 ftype=0

log      =internal log           bsize=1024   blocks=2564, version=2

=                       sectsz=512   sunit=0 blks, lazy-count=1

realtime =none                   extsz=4096   blocks=0, rtextents=0

#指定block 大小为1024

3.格式化为其他文件系统

[root@localhost ~]# mkfs.[tab][tab]

mkfs.btrfs   mkfs.ext2    mkfs.ext4    mkfs.minix   mkfs.vfat

mkfs.cramfs  mkfs.ext3    mkfs.fat     mkfs.msdos   mkfs.xfs

#列举出系统内可以格式化的文件系统类型

4.6.5检验

1.EXT4检验

[root@study ~]# fsck.ext4 [-pf]  装置名称

选项与参数：

-p  ：当档案系统在修复时，若有需要回覆 y 的动作时，自动回覆 y 来继续进行修复动作。

-f  ：强制检查！一般来说，如果 fsck 没有发现任何 unclean 的旗标，不会主动进入

细部检查的，如果您想要强制 fsck 进入细部检查，就得加上 -f 旗标！

[root@localhost Desktop]# fsck.ext4 /dev/sda3

e2fsck 1.42.9 (28-Dec-2013)

/dev/sda3: clean, 11/51200 files, 18515/204800 block

2.XFS检验

[root@study ~]# xfs_repair [-fnd] 装置名称

选项与参数：

-f  ：后面的装置其实是个档案而不是实体装置

-n  ：单纯检查并不修改档案系统的任何资料 (检查而已)

-d  ：通常用在单人维护模式底下，针对根目录 (/) 进行检查与修复的动作！很危险！不要随便使用

[root@localhost Desktop]# mkfs.xfs -f /dev/sda3

#先把前面实验用的ext4格式的sda3重新格式化为xfs文件系统。

[root@localhost Desktop]# xfs_repair /dev/sda3

Phase 1 - find and verify superblock...

Phase 2 - using internal log

- zero log...

- scan filesystem freespace and inode maps...

- found root inode chunk

Phase 3 - for each AG...

- scan and clear agi unlinked lists...

- process known inodes and perform inode discovery...

- agno = 0

- agno = 1

- agno = 2

- agno = 3

- process newly discovered inodes...

Phase 4 - check for duplicate blocks...

- setting up duplicate extent list...

- check for inodes claiming duplicate blocks...

- agno = 0

- agno = 1

- agno = 2

- agno = 3

Phase 5 - rebuild AG headers and trees...

- reset superblock...

Phase 6 - check inode connectivity...

- resetting contents of realtime bitmap and summary inodes

- traversing filesystem ...

- traversal finished ...

- moving disconnected inodes to lost+found ...

Phase 7 - verify and correct link counts...

done