Linux.分区、格式化、挂载

双系统 + 小硬盘 = ubuntu空间不够用

于是用win10自带的分区工具（右键计算机-管理-磁盘管理器）删掉了一个卷，大约24G，决定将这块空间挂载到ubuntu上

如今一块500G的SSD要一千块，实在买不起

系统与硬盘

niugen@niugenen:~$ uname -a
Linux niugenen 4.4.0-64-generic #85-Ubuntu SMP Mon Feb 20 11:50:30 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
niugen@niugenen:~$ sudo fdisk -l
[sudo] niugen 的密码：
Disk /dev/ram0: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram1: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram2: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram3: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram4: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram5: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram6: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram7: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram8: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram9: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram10: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram11: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram12: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram13: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram14: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/ram15: 64 MiB, 67108864 bytes, 131072 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk /dev/sda: 232.9 GiB, 250059350016 bytes, 488397168 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: 0x6d2d0206

设备       启动     Start    末尾    扇区   Size Id 类型
/dev/sda1  *         2048 169934847 169932800    81G  7 HPFS/NTFS/exFAT
/dev/sda2       169934848 394025327 224090480 106.9G  7 HPFS/NTFS/exFAT
/dev/sda3       394027006 435970047  41943042    20G  5 扩展
/dev/sda5       394027008 404025343   9998336   4.8G 83 Linux
/dev/sda6       404027392 405002239    974848   476M 83 Linux
/dev/sda7       405004288 407003135   1998848   976M 82 Linux 交换 / Solaris
/dev/sda8       407005184 411002879   3997696   1.9G 83 Linux
/dev/sda9       411004928 435970047  24965120  11.9G 83 Linux

Disk /dev/sdb: 931.5 GiB, 1000170586112 bytes, 1953458176 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: gpt
Disk identifier: 55333591-6989-44CA-9841-239B250B344E

设备       Start     末尾     扇区   Size 类型
/dev/sdb1   2048 1953456127 1953454080 931.5G Microsoft basic data

关于/dev/ram1这类设备的一篇博客

分区

从上文可见/dev/sda3是一个扩展分区，衍生出了/dev/sda56789这五个分区，目前我整个ubuntu也就是在这五个分区上

niugen@niugenen:~$ df
文件系统           1K-块      已用      可用 已用% 挂载点
udev             4010356         0   4010356    0% /dev
tmpfs             805972      9644    796328    2% /run
/dev/sda5        4789564   1675264   2847960   38% /
/dev/sda9       12155568   8783780   2731276   77% /usr
tmpfs            4029844     21112   4008732    1% /dev/shm
tmpfs               5120         4      5116    1% /run/lock
tmpfs            4029844         0   4029844    0% /sys/fs/cgroup
/dev/sda6         463844    105084    330293   25% /boot
/dev/sda8        1934672   1560648    257700   86% /home
tmpfs             805972        68    805904    1% /run/user/1000

也可见到，整块硬盘大小为232.9 GiB，但是所有的分区加起来才207GiB，也就是还有25G空间，那也就是我在win10上删掉的那个卷

给这25G分个区，过程根据提示输入command就好

n：add a new partition

分好后长这样

niugen@niugenen:~$ sudo fdisk /dev/sda
[sudo] niugen 的密码：

Welcome to fdisk (util-linux 2.27.1).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

命令(输入 m 获取帮助)： p
Disk /dev/sda: 232.9 GiB, 250059350016 bytes, 488397168 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: 0x6d2d0206

设备       启动     Start    末尾    扇区   Size Id 类型
/dev/sda1  *         2048 169934847 169932800    81G  7 HPFS/NTFS/exFAT
/dev/sda2       169934848 394025327 224090480 106.9G  7 HPFS/NTFS/exFAT
/dev/sda3       394027006 435970047  41943042    20G  5 扩展
/dev/sda4       435970048 488397167  52427120    25G 83 Linux
/dev/sda5       394027008 404025343   9998336   4.8G 83 Linux
/dev/sda6       404027392 405002239    974848   476M 83 Linux
/dev/sda7       405004288 407003135   1998848   976M 82 Linux 交换 / Solaris
/dev/sda8       407005184 411002879   3997696   1.9G 83 Linux
/dev/sda9       411004928 435970047  24965120  11.9G 83 Linux

Partition table entries are not in disk order.

命令(输入 m 获取帮助)： q

出现了/dev/sda4，大小为25G

格式化

$ mkfs -t ext4 /dev/sda4

挂载

$ mount /dev/sda4 /home/niugen/disk

之后就这样了

niugen@niugenen:~$ df -lhT
文件系统       类型      容量  已用  可用 已用% 挂载点
udev           devtmpfs  3.9G     0  3.9G    0% /dev
tmpfs          tmpfs     788M  9.5M  778M    2% /run
/dev/sda5      ext4      4.6G  1.6G  2.8G   38% /
/dev/sda9      ext4       12G  8.4G  2.7G   77% /usr
tmpfs          tmpfs     3.9G   14M  3.9G    1% /dev/shm
tmpfs          tmpfs     5.0M  4.0K  5.0M    1% /run/lock
tmpfs          tmpfs     3.9G     0  3.9G    0% /sys/fs/cgroup
/dev/sda6      ext4      453M  103M  323M   25% /boot
/dev/sda8      ext4      1.9G  1.5G  251M   86% /home
/dev/sda4      ext4       25G   44M   24G    1% /home/niugen/disk
tmpfs          tmpfs     788M   88K  787M    1% /run/user/1000
/dev/sdb1      fuseblk   932G  758G  175G   82% /media/niugen/Elements
/dev/sda2      fuseblk   107G   57G   51G   54% /media/niugen/0006FC6000004495

设置为开机自动挂载

$ sudo gedit /etc/fstab

加上我这里的最后一行

niugen@niugenen:~$ cat /etc/fstab
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
# / was on /dev/sda5 during installation
UUID=b5816071-6ad8-4676-bfd6-a3a780e2b574 /               ext4    errors=remount-ro 0       1
# /boot was on /dev/sda6 during installation
UUID=5fd70596-6fc0-4f4c-8b0e-3fe9eae8b605 /boot           ext4    defaults        0       2
# /home was on /dev/sda8 during installation
UUID=607b284d-802a-4a0e-bcab-efb2f1065fa6 /home           ext4    defaults        0       2
# /usr was on /dev/sda9 during installation
UUID=d7f6f351-05f5-454e-b63e-88cbdf0e440d /usr            ext4    defaults        0       2
# swap was on /dev/sda7 during installation
UUID=3354a04d-6019-43eb-be82-20de08126d9d none            swap    sw              0       0
/dev/sda4 /home/niugen/disk ext4 defaults 0 2

每行的格式在已有的注释里已经说出来了

# <file system> <mount point>   <type>  <options>       <dump>  <pass>

<源文件系统><挂载点><文件系统类型><选项>\< dump>\< pass>

dump：设置是否让备份程序dump备份文件系统，0为忽略，1为备份。

pass：告诉fsck程序以什么顺序检查文件系统，0为忽略。

我看其他的都是 0 2 ，于是我也写了0 2

搞定

关键还在于理解主分区、扩展分区、逻辑分区的概念，和他们之间的关系，才能搞清楚自己到底在干什么