Linux 主分区_扩展分区_逻辑分区
目录：
1、Linux分区介绍
2、创建主分区
3、创建扩展分区
4、创建逻辑分区
1、Linux分区介绍
1.1 分区规定：
每个磁盘设备最多4个主分区，或者3个主分区+1个扩展分区，是因为MBR（主引导记录）的分区表（主分区表）只能存放4个分区。
扩展分区只能有一个。
逻辑分区可以有多个。
可以从扩展分区中再次划分多个逻辑分区，逻辑分区编号直接从5开始。
1.2 分区作用：
主分区：主要是用来启动操作系统的，它主要放的是操作系统的启动或引导程序，/boot分区最好放在主分区上；
扩展分区是不能使用的，它只是做为逻辑分区的容器存在的，先创建一个扩展分区，在扩展分区之上创建逻辑分区；
我们真正存放数据的是主分区和逻辑分区，大量数据都放在逻辑分区中。
2、创建主分区
[ ~]# fdisk /dev/vdbCommand (m for help): n # 创建新分区
Partition type
p primary (0 primary, 0 extended, 4 free)
e extended (container for logical partitions)
Select (default p): p # 创建主分区
Partition number (1-4, default 1): # 回车
First sector (2048-10485759, default 2048): # 回车，设置起始扇区
Last sector, +sectors or +size{K,M,G,T,P} (2048-10485759, default 10485759): 409600 # 设置结尾扇区
Created a new partition 1 of type ‘Linux‘ and of size 199 MiB.
Command (m for help): n
Partition type
p primary (1 primary, 0 extended, 3 free)
e extended (container for logical partitions)
Select (default p): p # 创建主分区
Partition number (2-4, default 2): # 回车
First sector (409601-10485759, default 411648): # 回车，设置起始扇区
Last sector, +sectors or +size{K,M,G,T,P} (411648-10485759, default 10485759): 819200 # 设置结尾扇区
Created a new partition 2 of type ‘Linux‘ and of size 199 MiB.
Command (m for help): w # 保存配置
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
[ ~]# fdisk -l /dev/vdb
Disk /dev/vdb: 5 GiB, 5368709120 bytes, 10485760 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
Disklabel type: dos
Disk identifier: 0x03864530
Device Boot Start End Sectors Size Id Type
/dev/vdb1 2048 409600 407553 199M 83 Linux
/dev/vdb2 411648 819200 407553 199M 83 Linux3、创建扩展分区
[ ~]# fdisk /dev/vdbCommand (m for help): n # 创建新分区
Partition type
p primary (2 primary, 0 extended, 2 free)
e extended (container for logical partitions)
Select (default p): e # 创建扩展分区
Partition number (3,4, default 3): # 选择分区号
First sector (409601-10485759, default 821248): # 起始扇区
Last sector, +sectors or +size{K,M,G,T,P} (821248-10485759, default 10485759): # 结尾扇区
Created a new partition 3 of type ‘Extended‘ and of size 4.6 GiB.
Command (m for help): w # 保存配置
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
[ ~]# fdisk -l /dev/vdb
Disk /dev/vdb: 5 GiB, 5368709120 bytes, 10485760 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
Disklabel type: dos
Disk identifier: 0x03864530
Device Boot Start End Sectors Size Id Type
/dev/vdb1 2048 409600 407553 199M 83 Linux # 主分区
/dev/vdb2 411648 819200 407553 199M 83 Linux # 主分区
/dev/vdb3 821248 10485759 9664512 4.6G 5 Extended # 扩展分区4、创建逻辑分区
[ ~]# fdisk /dev/vdb
Command (m for help): n # 创建新分区
All space for primary partitions is in use. # 提示所有空间都已经分配给主分区使用
Adding logical partition 5 # 从扩展分区中，自动划分逻辑分区
First sector (823296-10485759, default 823296): # 起始扇区
Last sector, +sectors or +size{K,M,G,T,P} (823296-10485759, default 10485759): # 结尾扇区
Created a new partition 5 of type ‘Linux‘ and of size 4.6 GiB.
Command (m for help): t # 分区类型
Partition number (1-3,5, default 5):
Hex code (type L to list all codes): 8e # LVM类型
Changed type of partition ‘Linux‘ to ‘Linux LVM‘.
Command (m for help): w # 保存配置
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
[ ~]# fdisk -l /dev/vdb
Disk /dev/vdb: 5 GiB, 5368709120 bytes, 10485760 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
Disklabel type: dos
Disk identifier: 0x03864530
Device Boot Start End Sectors Size Id Type
/dev/vdb1 2048 409600 407553 199M 83 Linux
/dev/vdb2 411648 819200 407553 199M 83 Linux
/dev/vdb3 821248 10485759 9664512 4.6G 5 Extended
/dev/vdb5 823296 10485759 9662464 4.6G 8e Linux LVM
[ ~]# mkfs.xfs /dev/vdb5 # 格式化逻辑分区
meta-data=/dev/vdb5 isize=512 agcount=4, agsize=301952 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=1, sparse=1, rmapbt=0
= reflink=1
data = bsize=4096 blocks=1207808, 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
[ ~]# mount /dev/vdb5 /var/tmp # 挂载逻辑分区