linux 建立扩展分区大小

# 查看磁盘分区情况
sudo fdisk -l

# 进入fdisk交互界面
sudo fdisk /dev/sdb

# 在fdisk中创建扩展分区
Command (m for help): n
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): e
Partition number (1-4, default 1): 1
First sector (2048-20971519, default 2048): 
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-20971519, default 20971519): 
Using default value 20971519
Partition 1 of type Linux extended and of size 10G is set

Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.

# 格式化逻辑分区
sudo mkfs.ext4 /dev/sdb5

# 挂载逻辑分区
sudo mkdir /mnt/mydata
sudo mount /dev/sdb5 /mnt/mydata