4.文件系統
本章同步視頻：https://edu.51cto.com/sd/e4874
4.6 分區、格式化與掛載
4.6.4 格式化
[root@localhost ~]# mkfs.ext4 /dev/sda3
Block size=1024 (log=0) #block大小
Stride=0 blocks, Stripe width=0 blocks
10240 blocks (5.00%) reserved for the super user
Maximum filesystem blocks=33816576
8192 blocks per group, 8192 fragments per group
Superblock backups stored on blocks:
8193, 24577, 40961, 57345, 73729
Creating journal (4096 blocks): done
Writing superblocks and filesystem accounting information: done
[root@localhost ~]# dumpe2fs /dev/sda3
Filesystem volume name: <none>
Last mounted on: <not available>
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 created: Fri Mar 20 14:17:32 2020
Last write time: Fri Mar 20 14:17:32 2020
Last checked: Fri Mar 20 14:17:32 2020
Reserved blocks uid: 0 (user root)
Reserved blocks gid: 0 (group root)
Default directory hash: half_md4
Directory Hash Seed: e0a7d3c5-f805-41e1-8e51-116851e0108f
[root@localhost ~]# mkfs.ext4 -b 4096 /dev/sda3
[root@localhost ~]# mkfs.ext4 -I 256 /dev/sda3
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
data = bsize=4096 blocks=51200, imaxpct=25
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
[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
data = bsize=4096 blocks=51200, imaxpct=25
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大小爲512，-f是強制格式化一個已經格式化過的文件系統
[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
data = bsize=1024 blocks=204800, imaxpct=25
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
[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
4.6.5 檢驗
[root@study ~]# fsck.ext4 [-pf] 裝置名稱
-p ：當檔案系統在修復時，若有需要回覆 y 的動作時，自動回覆 y 來繼續進行修復動作。
-f ：強制檢查！一般來說，如果 fsck 沒有發現任何 unclean 的旗標，不會主動進入
細部檢查的，如果您想要強制 fsck 進入細部檢查，就得加上 -f 旗標！
[root@localhost Desktop]# fsck.ext4 /dev/sda3
/dev/sda3: clean, 11/51200 files, 18515/204800 block
[root@study ~]# xfs_repair [-fnd] 裝置名稱
-d ：通常用在單人維護模式底下，針對根目錄 (/) 進行檢查與修復的動作！很危險！不要隨便使用
[root@localhost Desktop]# mkfs.xfs -f /dev/sda3
#先把前面實驗用的ext4格式的sda3重新格式化爲xfs文件系統。
[root@localhost Desktop]# xfs_repair /dev/sda3
Phase 1 - find and verify superblock...
- scan filesystem freespace and inode maps...
- scan and clear agi unlinked lists...
- process known inodes and perform inode discovery...
- process newly discovered inodes...
Phase 4 - check for duplicate blocks...
- setting up duplicate extent list...
- check for inodes claiming duplicate blocks...
Phase 5 - rebuild AG headers and trees...
Phase 6 - check inode connectivity...
- resetting contents of realtime bitmap and summary inodes
- moving disconnected inodes to lost+found ...
Phase 7 - verify and correct link counts...