Manage disk partitions
> Format: fdisk /dev/sda
Note: can only point to devices and not partitions
> Parameters:
P : Displays the partition of the current hard disk, including unsaved changes
n: create new partition
e: extended partition
P : primary partition
d: delete a partition
w: save and exit
q: exit without saving
t: Modify the partition type
L : show all supported types
l : show all types supported by multi
Note: Although w saves and exits, but the kernel does not recognize it, you can use the command to view
Create a file system
Command: mkfs
Full name: make file system
Parameters: -t filesystem type partition
create log
mkfs -t ext3 = mkfs.ext3
Similar to view
Specially manage ext series files:
Command: mke2fs creates ext 2 filesystem by default
-j : Create an ext3 filesystem.
-b BLOCK_SIZE: Specify the block size, the default is 4096 , the available values are 1024, 2048 and 4096
-L LABEL: Specify the partition label
-m # : Specifies the percentage of blocks reserved for superusers
-i # : used to specify how many bytes of space to create an inode , the default is 8192 , the value given here should be 2^n times the block size
-N # : Specify the number of inodes
-F : Force filesystem creation
-E : User specifies additional filesystem attributes
Query or view related properties of disk devices
Command: blkid
Used to view or define volume labels
Command: e2lable device file volume label
Adjust the relevant properties of the file system
Command : tune2fs
Parameters: -j : Do not damage the original data, upgrade ext 2 to ext 3 , be careful not to downgrade
-L LABEL: set or modify the volume label
-m #调整预留百分比
-r# 指定预留块数
-o :设定默认挂载选项
Acl
-c: 指定挂载次数达到#此之后进行自检,0或 -1表示关闭 此功能
-i : 每挂载使用多少天后进行自检, 0 或-1 表示关闭 此功能
备注: -c 和 -i 使用的环境是大数据库读写时,正好达到自检时间,此时服务器性能会急剧下降
-l 显示超级快中的信息
dumpe2fs (可兼容 ext4)
命令 : dumpe2fs /dev/sdb1 = tune2fs -l /dev/sdb1
注意:显示内容中我们可以看到每个快组中free
Blocks (空闲块) ,对于使用的硬盘我们可能看到的空闲块是离散的,这意味着有碎片了
参数 -h :只想看超级块的信息
Fsck
解释; 解释并修复Linux 支持的所有文件系统
参数 -t
FSTYPE :指定文件系统类型 ,注意:如果不指定, fsck 会自动调用blkid检测是哪种类型。
-a: 自动修复
e2fsck
解释: 专用于修复 ext2/ext3文件系统
参数: -f : 强制检查
-p : 自动修复