关键词：创建文件系统的工具、检测及修复文件系统的工具、查看其属性的工具、调整文件系统的特性；
前言：
创建文件系统的工具：mkfs.ext2 , mkfs.ext3 , mkfs.ext4 , mkfs.xfs , …
检测及修复文件系统的工具：fsck.ext4 , fsck.xfs , …
查看文件系统属性的工具：dumpe2fs , tune2fs , …
调整文件系统的特性：tune2fs , …
1、内核级文件系统的组成部分
文件系统驱动：有内核提供；
文件系统管理工具：由用户空间的应用程序提供；
2、ext系列文件系统的管理工具
mkfs.ext4 , mkfs.xfs …
创建文件系统的命令：
mkfs -t ext4 = mkfs.ext4 = mke2fs -t ext4
mke2fs命令：
命令解释：
mke2fs – create an ext2/ext3/ext4 filesystem
命令用法：
mke2fs [ -c | -l filename ] [ -b block-size ] [ -D ] [ -f fragment-size ] [ -g blocks-per-group ] [ -G number-of-groups ] [ -i bytes-per-inode ] [ -I inode-size ] [ -j ] [ -J journal-options ] [ -N number-of-inodes ] [ -n ] [ -m reserved-blocks-percentage ] [ -o cre‐ator-os ] [ -O feature[,…] ] [ -q ] [ -r fs-revision-level ] [ -E extended-options ] [ -v ] [ -F ] [ -L volume-label ] [ -M last-mounted-directory ] [ -S ] [ -t fs-type ] [ -T usage-type ] [ -U UUID ] [ -V ] device [ blocks-count ]
mke2fs -O journal_dev [ -b block-size ] [ -L volume-label ] [ -n ] [ -q ] [ -v ] external-journal [ blocks-count ]
OPTIONS:
-t {ext2|ext3|ext4} : 指明要创建的文件系统类型；mkfs -t ext4 = mkfs.ext4 = mke2fs -t ext4
-b {1024|2048|4096} : 指明文件系统的块大小；
-L LABEL : 指明卷标名称；
-N number-of-inodes ： 指定inode的数量；
-m # : 指定为超级用户保留的文件系统块的百分比； “-m 3″表示预留3%的块空间； 默认预留5%；
-j : 创建有日志功能的文件系统ext3 ; 特例，mke2fs -j = mke2fs -t ext3 = mkfs -t ext3
-i n : bytes-per-inode ，指明inode与字节的比例；每个inode多少字节；
-O [^]FEATURE : 不带脱字符，表示指定特性创建文件系统；带脱字符，表示不带指定特性创建文件系统；
ext文件系统创建完成后，可根据需要更改某些特性：
——————————————-
e2label命令：卷标的查看与设定；
e2label – Change the label on an ext2/ext3/ext4 filesystem
e2label device :查看某个分区的卷标；
e2label device LABEL : 设定某个分区的卷标；
tune2fs命令 : 在ext2/ext3/ext4文件系统上调整可调的文件系统参数(可调整部分参数)；
tune2fs – adjust tunable filesystem parameters on ext2/ext3/ext4 filesystems
tune2fs [OPTIONS] device
NOTE : block size ，块大小在文件系统创建后是不能修改的；
可调整的部分参数：
预留块数量空间的百分比；
卷标名称；
文件系统类型；
OPTIONS:
-l : 查看超级块的内容；
-L LABEL : 修改卷标；
-m # : 调整预留空间百分比(预留块数量)；
-j : 把ext2文件系统升级为ext3文件系统；
-O [^]FEATURE : 开启或关闭文件系统的某种特性；
-o [^]mount_options : 开启或关闭某种默认挂载选项；
dumpe2fs命令： 显示ext系列文件系统的属性信息；
dumpe2fs – dump ext2/ext3/ext4 filesystem information
dumpe2fs device : 显示超级块信息，以及所有块组的信息；
dumpe2fs -h device : 仅显示超级块信息；
3、blkid ：定位/打印块设备属性(比如，卷标名称，UUID,文件系统类型等)；
blkid – locate/print block device attributes
~]# blkid /dev/sdb1
blkid device : 定位/打印块设备属性；
blkid -L LABEL : 根据LABEL(卷标名)来定位设备(分区)；
blkid -U UUID : 更具UUID来定位设备；
4、文件系统的检测修复工具
因进程意外终止或系统崩溃等原因导致定稿操作非正常终止时，可能会造成文件损坏；
此时，应该要在离线状态下检测并修复文件系统(文件系统在非挂载状态下)；
4.1 ext系列文件系统的专用检测修复工具
e2fsck – check a Linux ext2/ext3/ext4 file system
e2fsck [OPTIONS] device
OPTIONS:
-y : 对所有问题自动回答为yes;
-f : 即使文件系统处于clean状态，也要强制进行检测；
4.2 通用文件系统的检测修复工具
fsck – check and repair a Linux filesystem
fsck [OPTIONS] device
OPTIONS:
-t fstype : 指明要检测修复的文件系统的类型；
## fsck -t ext4 = fsck.ext4
-a : 无须交互而自动修复所有错误；不推荐使用；
-r : 交互式检测修复；
5、swap文件系统
Linux系统上的交换分区必须使用独立的文件系统；且文件系统的System ID必须为82；
mkswap命令：创建swap设备；
mkswap [OPTIONS] divice
OPTIONS:
-L LABEL :指明卷标名称；
-f : 强制创建；
Windows无法识别Linux的文件系统；
存储设备需要在Windows和Linux系统交叉使用时，应该把存储设备格式化为vfat文件系统；mkfs.vfat device ;
启用交换分区：
swapon [OPTION] [DEVICE]
swapon -a : 启用定义在’/etc/fstab’文件中的所有swap设备；
禁用交换分区：
swapoff DEVICE
lsmod : 查看当前内核已装载的模块；可以通过编译进内核的方式或者加载进内核的方式来装载模块；
[root@localhost tmp]# lsmod Module Size Used by snd_seq_midi 13565 0 snd_seq_midi_event 14899 1 snd_seq_midi iosf_mbi 13523 0 crc32_pclmul 13113 0 ghash_clmulni_intel 13259 0 aesni_intel 69884 0 lrw 13286 1 aesni_intel gf128mul 14951 1 lrw glue_helper 13990 1 aesni_intel ablk_helper 13597 1 aesni_intel cryptd 20359 3 ghash_clmulni_intel,aesni_intel,ablk_helper ppdev 17671 0 snd_ens1371 25194 0 joydev 17377 0 vmw_balloon 18190 0 snd_rawmidi 31294 2 snd_ens1371,snd_seq_midi pcspkr 12718 0 snd_ac97_codec 130556 1 snd_ens1371 btusb 41436 0 ac97_bus 12730 1 snd_ac97_codec btrtl 12945 1 btusb btbcm 14040 1 btusb snd_seq 62699 2 snd_seq_midi_event,snd_seq_midi btintel 15709 1 btusb snd_seq_device 14356 3 snd_seq,snd_rawmidi,snd_seq_midi bluetooth 548687 5 btbcm,btrtl,btusb,btintel snd_pcm 106416 2 snd_ac97_codec,snd_ens1371 snd_timer 29810 2 snd_pcm,snd_seq snd 83383 7 snd_ac97_codec,snd_timer,snd_pcm,snd_seq,snd_rawmidi,snd_ens1371,snd_seq_device soundcore 15047 1 snd rfkill 22391 1 bluetooth nfit 49183 0 sg 40721 0 libnvdimm 132047 1 nfit parport_pc 28165 0 parport 46395 2 ppdev,parport_pc i2c_piix4 22390 0 shpchp 37032 0 vmw_vmci 67013 0 ip_tables 27078 0 xfs 978100 2 libcrc32c 12644 1 xfs sr_mod 22416 0 cdrom 42556 1 sr_mod ata_generic 12910 0 pata_acpi 13038 0 sd_mod 46322 4 crc_t10dif 12714 1 sd_mod crct10dif_generic 12647 0 vmwgfx 239501 1 drm_kms_helper 163265 1 vmwgfx syscopyarea 12529 1 drm_kms_helper sysfillrect 12701 1 drm_kms_helper sysimgblt 12640 1 drm_kms_helper fb_sys_fops 12703 1 drm_kms_helper ttm 99345 1 vmwgfx crct10dif_pclmul 14289 1 crct10dif_common 12595 3 crct10dif_pclmul,crct10dif_generic,crc_t10dif crc32c_intel 22079 1 drm 370825 4 ttm,drm_kms_helper,vmwgfx ata_piix 35038 0 serio_raw 13413 0 mptspi 22542 3 libata 242992 3 pata_acpi,ata_generic,ata_piix scsi_transport_spi 30732 1 mptspi mptscsih 40150 1 mptspi e1000 137500 0 mptbase 105960 2 mptspi,mptscsih i2c_core 40756 3 drm,i2c_piix4,drm_kms_helper dm_mirror 22124 0 dm_region_hash 20813 1 dm_mirror dm_log 18411 2 dm_region_hash,dm_mirror dm_mod 123303 10 dm_log,dm_mirror [root@localhost tmp]#
举例：磁盘分区操作；
[root@localhost ~]#
[root@localhost ~]# fdisk -l 查看是否有尚未分区的磁盘空间；
Disk /dev/sda: 42.9 GB, 42949672960 bytes, 83886080 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x000c32e3
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 2099199 1048576 83 Linux
/dev/sda2 2099200 83886079 40893440 8e Linux LVM
Disk /dev/sdb: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/mapper/centos-root: 39.7 GB, 39720058880 bytes, 77578240 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/mapper/centos-swap: 2147 MB, 2147483648 bytes, 4194304 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
[root@localhost ~]#
[root@localhost ~]#
[root@localhost ~]# fdisk /dev/sdb 对 /dev/sdb 磁盘进行分区操作；
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0xfead7da1.
Command (m for help): m 显示可用子命令；
Command action
a toggle a bootable flag
b edit bsd disklabel
c toggle the dos compatibility flag
d delete a partition
g create a new empty GPT partition table
G create an IRIX (SGI) partition table
l list known partition types
m print this menu
n add a new partition
o create a new empty DOS partition table
p print the partition table
q quit without saving changes
s create a new empty Sun disklabel
t change a partition's system id
u change display/entry units
v verify the partition table
w write table to disk and exit
x extra functionality (experts only)
Command (m for help): p 显示 /dev/sdb 磁盘是否已有分区；
Disk /dev/sdb: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0xfead7da1
Device Boot Start End Blocks Id System
Command (m for help): l 显示所有已知分区的类型及对应的ID号；
0 Empty 24 NEC DOS 81 Minix / old Lin bf Solaris
1 FAT12 27 Hidden NTFS Win 82 Linux swap / So c1 DRDOS/sec (FAT-
2 XENIX root 39 Plan 9 83 Linux c4 DRDOS/sec (FAT-
3 XENIX usr 3c PartitionMagic 84 OS/2 hidden C: c6 DRDOS/sec (FAT-
4 FAT16 <32M 40 Venix 80286 85 Linux extended c7 Syrinx
5 Extended 41 PPC PReP Boot 86 NTFS volume set da Non-FS data
6 FAT16 42 SFS 87 NTFS volume set db CP/M / CTOS / .
7 HPFS/NTFS/exFAT 4d QNX4.x 88 Linux plaintext de Dell Utility
8 AIX 4e QNX4.x 2nd part 8e Linux LVM df BootIt
9 AIX bootable 4f QNX4.x 3rd part 93 Amoeba e1 DOS access
a OS/2 Boot Manag 50 OnTrack DM 94 Amoeba BBT e3 DOS R/O
b W95 FAT32 51 OnTrack DM6 Aux 9f BSD/OS e4 SpeedStor
c W95 FAT32 (LBA) 52 CP/M a0 IBM Thinkpad hi eb BeOS fs
e W95 FAT16 (LBA) 53 OnTrack DM6 Aux a5 FreeBSD ee GPT
f W95 Ext'd (LBA) 54 OnTrackDM6 a6 OpenBSD ef EFI (FAT-12/16/
10 OPUS 55 EZ-Drive a7 NeXTSTEP f0 Linux/PA-RISC b
11 Hidden FAT12 56 Golden Bow a8 Darwin UFS f1 SpeedStor
12 Compaq diagnost 5c Priam Edisk a9 NetBSD f4 SpeedStor
14 Hidden FAT16 <3 61 SpeedStor ab Darwin boot f2 DOS secondary
16 Hidden FAT16 63 GNU HURD or Sys af HFS / HFS+ fb VMware VMFS
17 Hidden HPFS/NTF 64 Novell Netware b7 BSDI fs fc VMware VMKCORE
18 AST SmartSleep 65 Novell Netware b8 BSDI swap fd Linux raid auto
1b Hidden W95 FAT3 70 DiskSecure Mult bb Boot Wizard hid fe LANstep
1c Hidden W95 FAT3 75 PC/IX be Solaris boot ff BBT
1e Hidden W95 FAT1 80 Old Minix
Command (m for help): n 创建新分区；
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p): p 选择创建主分区；
Partition number (1-4, default 1): 1 选择主分区号；
First sector (2048-41943039, default 2048): 选择新分区的起始扇区；
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-41943039, default 41943039): +1G 指定新分区的大小；
Partition 1 of type Linux and of size 1 GiB is set
Command (m for help): p 显示已有的所有分区；但此时看到的信息是记录在内存中的；
Disk /dev/sdb: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0xfead7da1
Device Boot Start End Blocks Id System
/dev/sdb1 2048 2099199 1048576 83 Linux
Command (m for help): w 保存新创建分区的信息至磁盘；
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@localhost ~]# kpartx -af /dev/sdb 强制内核更新分区表；
[root@localhost ~]#
[root@localhost ~]# cat /proc/partitions 查看内核已识别的所有分区， /dev/sdb1 能看到，表示分区已被识别；
major minor #blocks name
8 0 41943040 sda
8 1 1048576 sda1
8 2 40893440 sda2
8 16 20971520 sdb
8 17 1048576 sdb1
11 0 1048575 sr0
253 0 38789120 dm-0
253 1 2097152 dm-1
253 2 1048576 dm-2
[root@localhost ~]#
创建 xfs 文件系统，并挂载：
[root@localhost ~]# df -lh
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 37G 1.9G 36G 5% /
devtmpfs 478M 0 478M 0% /dev
tmpfs 488M 0 488M 0% /dev/shm
tmpfs 488M 6.7M 481M 2% /run
tmpfs 488M 0 488M 0% /sys/fs/cgroup
/dev/sda1 1014M 153M 862M 16% /boot
tmpfs 98M 0 98M 0% /run/user/0
[root@localhost ~]# mkfs.xfs /dev/sdb1
meta-data=/dev/sdb1 isize=512 agcount=4, agsize=65536 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0, sparse=0
data = bsize=4096 blocks=262144, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal log bsize=4096 blocks=2560, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
[root@localhost ~]#
[root@localhost ~]# mount /dev/sdb1 /sdb1
[root@localhost ~]#
[root@localhost ~]# df -lh
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 37G 1.9G 36G 5% /
devtmpfs 478M 0 478M 0% /dev
tmpfs 488M 0 488M 0% /dev/shm
tmpfs 488M 6.7M 481M 2% /run
tmpfs 488M 0 488M 0% /sys/fs/cgroup
/dev/sda1 1014M 153M 862M 16% /boot
tmpfs 98M 0 98M 0% /run/user/0
/dev/sdb1 1014M 33M 982M 4% /sdb1
[root@localhost ~]#
创建 ext4 文件系统并挂载：
[root@localhost ~]# mkfs.ext4 /dev/sdb2 mke2fs 1.42.9 (28-Dec-2013) Filesystem label= OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) Stride=0 blocks, Stripe width=0 blocks 131072 inodes, 524288 blocks 26214 blocks (5.00%) reserved for the super user First data block=0 Maximum filesystem blocks=536870912 16 block groups 32768 blocks per group, 32768 fragments per group 8192 inodes per group Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912 Allocating group tables: done Writing inode tables: done Creating journal (16384 blocks): done Writing superblocks and filesystem accounting information: done [root@localhost ~]# mkdir /sdb2 [root@localhost ~]# [root@localhost ~]# mount /dev/sdb2 /sdb2 [root@localhost ~]# [root@localhost ~]# df -lh Filesystem Size Used Avail Use% Mounted on /dev/mapper/centos-root 37G 1.9G 36G 5% / devtmpfs 478M 0 478M 0% /dev tmpfs 488M 0 488M 0% /dev/shm tmpfs 488M 6.7M 481M 2% /run tmpfs 488M 0 488M 0% /sys/fs/cgroup /dev/sda1 1014M 153M 862M 16% /boot tmpfs 98M 0 98M 0% /run/user/0 /dev/sdb1 1014M 33M 982M 4% /sdb1 /dev/sdb2 2.0G 6.0M 1.8G 1% /sdb2 [root@localhost ~]#
举例：查看某个分区的UUID，以及此分区的文件系统类型；
[root@localhost ~]# blkid /dev/sdb1 /dev/sdb1: UUID="ff2b0019-4dc9-4bb3-b2ba-43b7ecdb76c0" TYPE="xfs" [root@localhost ~]# [root@localhost ~]# blkid /dev/sdb2 /dev/sdb2: UUID="6573bffb-af78-4ea2-b4d1-d2303cab8cad" TYPE="ext4" [root@localhost ~]#
举例：tune2fs -l 显示的内容说明；
[root@localhost ~]# [root@localhost ~]# tune2fs -l /dev/sdb1 tune2fs 1.42.9 (28-Dec-2013) tune2fs: Bad magic number in super-block while trying to open /dev/sdb1 Couldn't find valid filesystem superblock. [root@localhost ~]# [root@localhost ~]# tune2fs -l /dev/sdb2 tune2fs 1.42.9 (28-Dec-2013) Filesystem volume name: <none> ## 卷标名称； Last mounted on: <not available> ## 表示尚未挂载使用； Filesystem UUID: 6573bffb-af78-4ea2-b4d1-d2303cab8cad ## UUID号码； Filesystem magic number: 0xEF53 ## 文件系统的魔数； Filesystem revision #: 1 (dynamic) Filesystem features: has_journal ext_attr resize_inode dir_index filetype needs_recovery extent 64bit flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize ## 已启用的特性； Filesystem flags: signed_directory_hash Default mount options: user_xattr acl Filesystem state: clean Errors behavior: Continue Filesystem OS type: Linux Inode count: 131072 Block count: 524288 Reserved block count: 26214 Free blocks: 498132 Free inodes: 131061 First block: 0 Block size: 4096 Fragment size: 4096 Group descriptor size: 64 Reserved GDT blocks: 255 Blocks per group: 32768 Fragments per group: 32768 Inodes per group: 8192 Inode blocks per group: 512 Flex block group size: 16 Filesystem created: Sat May 5 01:25:22 2018 Last mount time: Sat May 5 01:25:44 2018 Last write time: Sat May 5 01:25:44 2018 Mount count: 1 Maximum mount count: -1 Last checked: Sat May 5 01:25:22 2018 Check interval: 0 (<none>) Lifetime writes: 65 MB Reserved blocks uid: 0 (user root) Reserved blocks gid: 0 (group root) First inode: 11 Inode size: 256 Required extra isize: 28 Desired extra isize: 28 Journal inode: 8 Default directory hash: half_md4 Directory Hash Seed: 74f98009-f20c-4688-8ba0-9108c8c8a196 Journal backup: inode blocks [root@localhost ~]#
举例：dumpe2fs 显示超级块信息、以及所有块组的信息；
[root@localhost /]# [root@localhost /]# dumpe2fs -h /dev/sdb2 dumpe2fs 1.42.9 (28-Dec-2013) Filesystem volume name: <none> Last mounted on: <not available> Filesystem UUID: 6573bffb-af78-4ea2-b4d1-d2303cab8cad 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 large_file 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: 131072 Block count: 524288 Reserved block count: 26214 Free blocks: 498132 Free inodes: 131061 First block: 0 Block size: 4096 Fragment size: 4096 Group descriptor size: 64 Reserved GDT blocks: 255 Blocks per group: 32768 Fragments per group: 32768 Inodes per group: 8192 Inode blocks per group: 512 Flex block group size: 16 Filesystem created: Sat May 5 01:25:22 2018 Last mount time: Sat May 5 01:25:44 2018 Last write time: Sat May 5 03:29:18 2018 Mount count: 1 Maximum mount count: -1 Last checked: Sat May 5 01:25:22 2018 Check interval: 0 (<none>) Lifetime writes: 99 MB Reserved blocks uid: 0 (user root) Reserved blocks gid: 0 (group root) First inode: 11 Inode size: 256 Required extra isize: 28 Desired extra isize: 28 Journal inode: 8 Default directory hash: half_md4 Directory Hash Seed: 74f98009-f20c-4688-8ba0-9108c8c8a196 Journal backup: inode blocks Journal features: journal_64bit Journal size: 64M Journal length: 16384 Journal sequence: 0x00000004 Journal start: 0 [root@localhost /]# dumpe2fs /dev/sdb2 |more dumpe2fs 1.42.9 (28-Dec-2013) Filesystem volume name: <none> Last mounted on: <not available> Filesystem UUID: 6573bffb-af78-4ea2-b4d1-d2303cab8cad 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 large_file huge_file uninit_bg di r_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: 131072 Block count: 524288 Reserved block count: 26214 Free blocks: 498132 Free inodes: 131061 First block: 0 Block size: 4096 Fragment size: 4096 Group descriptor size: 64 Reserved GDT blocks: 255 Blocks per group: 32768 Fragments per group: 32768 Inodes per group: 8192 Inode blocks per group: 512 Flex block group size: 16 Filesystem created: Sat May 5 01:25:22 2018 Last mount time: Sat May 5 01:25:44 2018 Last write time: Sat May 5 03:29:18 2018 Mount count: 1 Maximum mount count: -1 Last checked: Sat May 5 01:25:22 2018 Check interval: 0 (<none>) Lifetime writes: 99 MB Reserved blocks uid: 0 (user root) Reserved blocks gid: 0 (group root) First inode: 11 Inode size: 256 Required extra isize: 28 Desired extra isize: 28 Journal inode: 8 Default directory hash: half_md4 Directory Hash Seed: 74f98009-f20c-4688-8ba0-9108c8c8a196 Journal backup: inode blocks Journal features: journal_64bit Journal size: 64M Journal length: 16384 Journal sequence: 0x00000004 Journal start: 0 Group 0: (Blocks 0-32767) [ITABLE_ZEROED] Checksum 0x5c5b, unused inodes 8181 Primary superblock at 0, Group descriptors at 1-1 Reserved GDT blocks at 2-256 Block bitmap at 257 (+257), Inode bitmap at 273 (+273) Inode table at 289-800 (+289) 24281 free blocks, 8181 free inodes, 2 directories, 8181 unused inodes Free blocks: 8487-32767 Free inodes: 12-8192 Group 1: (Blocks 32768-65535) [INODE_UNINIT, ITABLE_ZEROED] Checksum 0xaf3b, unused inodes 8192 Backup superblock at 32768, Group descriptors at 32769-32769 Reserved GDT blocks at 32770-33024 Block bitmap at 258 (bg #0 + 258), Inode bitmap at 274 (bg #0 + 274) Inode table at 801-1312 (bg #0 + 801) 32511 free blocks, 8192 free inodes, 0 directories, 8192 unused inodes Free blocks: 33025-65535 Free inodes: 8193-16384 Group 2: (Blocks 65536-98303) [INODE_UNINIT, BLOCK_UNINIT, ITABLE_ZEROED] Checksum 0x814c, unused inodes 8192 ... ...