linux管理储存设备和磁盘分区

管理系统存储

一、查看系统中的设备
1、发现系统中的设备

fdisk -l 查看系统中真实存在的设备

cat /proc/partitions 查看系统中被系统识别的设备

2、blkid 系统发现的，并系统利用的，有id信息的设备

3、发现并且在挂载的设备

df -h

df -H

二、设备名称的理解
/dev/sda1                  sata硬盘，或者iscsi网络存储（v表示虚拟硬盘，h表示ide硬盘，一般出现在老式电脑中）a1表示第一块硬盘中的第一个分区
/dev/cdrom                 光驱
/dev/mapper/*              系统中的虚拟设备
三、设备的使用
设备必须要用目录来对设备中的内容进行读取
所以设备在使用时需要作挂在动作
1，挂载设备
blkid                      识别可用设备

mount /dev/vdb1 /mnt 把系统中的第二块硬盘下的第一个分区挂载到mnt下

mount -o ro /dev/vdb1 /mnt/只读挂载第二块硬盘下的第一个分区到/mnt下

mount -o remount,rw /mnt 在设备被使用时梗概设备的挂载参数为rw

2，设备卸载

umount 设备（挂载点） umount /dev/vdb1（/mnt）

当卸载设备时出现下列情况，表示设备正在被系统的某个程序使用
umount: /mnt: target is busy.
        (In some cases useful info about processes that use
         the device is found by lsof(8) or fuser(1))
一般原因是因为当前路径在此挂载点，或者此目录下有进程
四、分区管理
1、mbr主引导记录446个字节
2、mtp主分区表64个字节
3、硬盘的有效性标示“55aa”占用2字节
4、一个主分区占用16个字节记录分区信息
5、一块硬盘上如果用mbr的分区方式最多可以存在4个主分区
6、主分区                 主分区表记录主分区
7、拓展分区               主分区表记录拓展分区
8、逻辑分区               拓展分区记录逻辑分区

分区的划分

fdisk -l 查找当前可用于分区的设备

fdisk /dev/vdb

Welcome to fdisk (util-linux 2.23.2).

Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Command (m for help): m        获得帮助
Command action
   a   toggle a bootable flag
   b   edit bsd disklabel
   c   toggle the dos compatibility flag
   d   delete a partition         删除分区
   g   create a new empty GPT partition table
   G   create an IRIX (SGI) partition table
   l   list known partition types
   m   print this menu
   n   add a new partition         新建分区
   o   create a new empty DOS partition table
   p   print the partition table   显示分区标信息
   q   quit without saving changes 退出
   s   create a new empty Sun disklabel
   t   change a partition's system id   修改分区id
   u   change display/entry units
   v   verify the partition table
   w   write table to disk and exit   将当前操作写入硬盘分区（如不w保存，则之前分区操作不被记录）
   x   extra functionality (experts only)

Command (m for help): n 新建分区

Partition type:
   p   primary (0 primary, 0 extended, 4 free)    分区类型 p主分区
   e   extended                                    e 扩展分区
Select (default p): p                  选择主分区
Partition number (1-4, default 1):1    选择主分区编号
First sector (2048-20971519, default 2048):设置起始扇区默认2048开始
Last sector, +sectors or +size{K,M,G} (2048-20971519, default 20971519):设置终止扇区
Partition 1 of type Linux and of size 100 MiB is set 建立成功
Command (m for help): wq        保存推出，如果安q表示放弃更改退出

[root@localhost mnt]# partprobe     同步分区表

cat /proc/partitions 查看系统识别的分区信息

mkfs.xfs /dev/vdb2 格式化

mount /dev/vdb2 /mnt 临时挂载

vim /etc/fstab 永久挂载
/dev/vdb2 /mnt xfs defaults 0 0

mount -a 使/etc/fstab中记录的挂载策略生效

设定分区方式为gpt

[root@server0 ~]# parted /dev/vdb
GNU Parted 3.1
Using /dev/vdb
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) mklabel
New disk label type? gpt
Warning: The existing disk label on /dev/vdb will be destroyed and all data on this disk will be lost. Do you
want to continue?
Yes/No? y

(parted) quit

mkfs.xfs /dev/vdb 格式化挂载文件

格式化后重新分区fdisk /dev/vdb看效果

swap分区

swapon -s 查看有没有syapon分区

[root@node2 ~]# fdisk /dev/vdb 新建分区，并修改分区ip为swapon分区id

Welcome to fdisk (util-linux 2.23.2).

Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.

Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0x6eadbf6f.

Command (m for help): n
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): p
Partition number (1-4, default 1):
First sector (2048-20971519, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-20971519, default 20971519): +1000M
Partition 1 of type Linux and of size 1000 MiB is set

Command (m for help): p

Disk /dev/vdb: 10.7 GB, 10737418240 bytes, 20971520 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
Disk label type: dos
Disk identifier: 0x6eadbf6f

   Device Boot      Start         End      Blocks   Id System
/dev/vdb1            2048     2050047     1024000   83 Linux

Command (m for help): t
Selected partition 1
Hex code (type L to list all codes): l

0 Empty           24 NEC DOS         81 Minix / old Lin bf Solaris
1 FAT12           27 Hidden NTFS Win 82 Linux swap / So c1 DRDOS/sec (FAT-
2 XENIX root      39 Plan 9          83 Linux           c4 DRDOS/sec (FAT-
3 XENIX usr       3c PartitionMagic 84 OS/2 hidden C: c6 DRDOS/sec (FAT-
4 FAT16 <32M      40 Venix 80286     85 Linux extended c7 Syrinx
5 Extended        41 PPC PReP Boot   86 NTFS volume set da Non-FS data
6 FAT16           42 SFS             87 NTFS volume set db CP/M / CTOS / .
7 HPFS/NTFS/exFAT 4d QNX4.x          88 Linux plaintext de Dell Utility
8 AIX             4e QNX4.x 2nd part 8e Linux LVM       df BootIt
9 AIX bootable    4f QNX4.x 3rd part 93 Amoeba          e1 DOS access
a OS/2 Boot Manag 50 OnTrack DM      94 Amoeba BBT      e3 DOS R/O
b W95 FAT32       51 OnTrack DM6 Aux 9f BSD/OS          e4 SpeedStor
c W95 FAT32 (LBA) 52 CP/M            a0 IBM Thinkpad hi eb BeOS fs
e W95 FAT16 (LBA) 53 OnTrack DM6 Aux a5 FreeBSD         ee GPT
f W95 Ext'd (LBA) 54 OnTrackDM6      a6 OpenBSD         ef EFI (FAT-12/16/
10 OPUS            55 EZ-Drive        a7 NeXTSTEP        f0 Linux/PA-RISC b
11 Hidden FAT12    56 Golden Bow      a8 Darwin UFS      f1 SpeedStor
12 Compaq diagnost 5c Priam Edisk     a9 NetBSD          f4 SpeedStor
14 Hidden FAT16 <3 61 SpeedStor       ab Darwin boot     f2 DOS secondary
16 Hidden FAT16    63 GNU HURD or Sys af HFS / HFS+      fb VMware VMFS
17 Hidden HPFS/NTF 64 Novell Netware b7 BSDI fs         fc VMware VMKCORE
18 AST SmartSleep 65 Novell Netware b8 BSDI swap       fd Linux raid auto
1b Hidden W95 FAT3 70 DiskSecure Mult bb Boot Wizard hid fe LANstep
1c Hidden W95 FAT3 75 PC/IX           be Solaris boot    ff BBT
1e Hidden W95 FAT1 80 Old Minix
Hex code (type L to list all codes): 82
Changed type of partition 'Linux' to 'Linux swap / Solaris'

Command (m for help): p

Disk /dev/vdb: 10.7 GB, 10737418240 bytes, 20971520 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
Disk label type: dos
Disk identifier: 0x6eadbf6f

   Device Boot      Start         End      Blocks   Id System
/dev/vdb1            2048     2050047     1024000   82 Linux swap / Solaris

Command (m for help): wq
The partition table has been altered!

Calling ioctl() to re-read partition table.

Syncing disks.

[root@node2 ~]# mkswap /dev/vdb2 将/dev/vdb2分区设置为linux的交换去

Setting up swapspace version 1, size = 1023996 KiB

no label, UUID=28c3c77b-91f3-4098-9736-2d694a870c22

[root@node2 ~]# swapon -a /dev/vdb1      启动/dev/vdb2分区swap装置
[root@node2 ~]# swapon -s                显示swap分区
Filename               Type       Size   Used   Priority

/dev/vdb2 partition 1023996 0 -1

[root@node2 ~]# vim /etc/fstab 永久修改

/dev/vdb2 swap swap defaults 0 0

删除swap分区

swapoff /dev/vdb2

删除配置文件里边的配置

分区配额

通过mount查看是否开启配额（noquota表示没有开启，usrquota表示开启配额）
如果显示没有开启配额需要卸载掉重新挂载，并在挂载的时候开启配额

mount -o usrquota /dev/vdb2 /mnt/ 挂载并开启配额

edquota -u student 给student用户配额
Disk quotas for user student (uid 1000):
Filesystem blocks soft hard inodes soft hard

/dev/vdb2 0 0 20480 0 0 0

此修改为临时修改，如果永久设定需要修改 /etc/fstab文件

/dev/vdb2 /mnt xfs defaults,usrquota 0 0

切换到student用户测试,在测试前先给/mnt目录权限给到777

[student@node2 ~]$ dd if=/dev/zero of=/mnt/studentfile bs=1M count=30

dd: error writing ‘/mnt/studentfile’: Disk quota exceeded
21+0 records in
20+0 records out
20971520 bytes (21 MB) copied, 0.00945847 s, 2.2 GB/s

磁盘加密

1磁盘加密
fdisk /dev/vdb                                  新建一个磁盘
cryptsetup luksFormat /dev/vdb1                  给这个磁盘设置磁盘加密，并设置密码
cryptsetup open /dev/vdb1 westos                 将这个加密磁盘打开
mkfs.xfs /dev/mapper/westos                     格式化磁盘

mount /dev/mapper/westos /mnt/ 将该磁盘挂载

umount /mnt/ 卸载磁盘

cryptsetup close westos 关闭加密磁盘

实验：
[root@node2 ~]# cryptsetup luksFormat /dev/vdb1

WARNING!
========
This will overwrite data on /dev/vdb1 irrevocably.

Are you sure? (Type uppercase yes): YES
Enter passphrase:
Verify passphrase:
[root@node2 ~]# cryptsetup open /dev/vdb1 westos
Enter passphrase for /dev/vdb1:
[root@node2 ~]# ll   /dev/mapper/westos
lrwxrwxrwx. 1 root root 7 Apr 16 22:44 /dev/mapper/westos -> ../dm-0
[root@node2 ~]# mkfs.xfs /dev/mapper/westos
meta-data=/dev/mapper/westos     isize=256    agcount=4, agsize=31872 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=0
data     =                       bsize=4096   blocks=127488, imaxpct=25
         =                       sunit=0      swidth=0 blks
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@node2 ~]# mount /dev/mapper/westos /mnt/
[root@node2 ~]# df
Filesystem         1K-blocks    Used Available Use% Mounted on
/dev/vda1           10473900 3703460   6770440 36% /
devtmpfs              469344       0    469344   0% /dev
tmpfs                 484932      84    484848   1% /dev/shm
tmpfs                 484932   12800    472132   3% /run
tmpfs                 484932       0    484932   0% /sys/fs/cgroup
/dev/mapper/westos    506540   25656    480884   6% /mnt
[root@node2 ~]# ls /mnt/
[root@node2 ~]# touch /mnt/file{1..4}
[root@node2 ~]# ls /mnt/
file1 file2 file3 file4
[root@node2 ~]# umount /mnt/
[root@node2 ~]# ls /mnt/
[root@node2 ~]# cryptsetup open /dev/vdb1 redhat
Enter passphrase for /dev/vdb1:
[root@node2 ~]# mount /dev/mapper/redhat /mnt/
[root@node2 ~]# ls /mnt/
file1 file2 file3 file4
[root@node2 ~]# umount /mnt/
[root@node2 ~]# cryptsetup close westos
Device westos is not active.
2、加密磁盘开机自动挂载
[root@node2 ~]# vim /root/diskpass        写入磁盘密码

[root@node2 ~]# chmod 600 /root/diskpass 将磁盘权限设置成只对超级用户可操作

[root@node2 ~]# vim /etc/crypttab 写入磁盘名称，磁盘设备，以及磁盘密码所在文件

westos /dev/vdb1 /root/diskpass

[root@node2 ~]# vim /etc/fstab 修改配置文件

/dev/mapper/westos /mnt xfs defaults 0 0
[root@node2 ~]# cryptsetup luksAddKey /dev/vdb1 /root/diskpass 告诉系统加密磁盘的密码指定

Enter any passphrase:

[root@node2 ~]# reboot

[root@node2 ~]# df

Filesystem         1K-blocks    Used Available Use% Mounted on
/dev/vda1           10473900 3704528   6769372 36% /
devtmpfs              469344       0    469344   0% /dev
tmpfs                 484932      80    484852   1% /dev/shm
tmpfs                 484932   12760    472172   3% /run
tmpfs                 484932       0    484932   0% /sys/fs/cgroup
/dev/mapper/westos    506540   25656    480884   6% /mnt
3加密磁盘开机自动挂载的清除
[root@node2 ~]# vim /etc/fstab        删除掉配置文件里面的设定
[root@node2 ~]# umount /mnt/          卸载挂载
[root@node2 ~]# vim /etc/crypttab     删除里面的内容指定
[root@node2 ~]# rm -fr /root/diskpass 删除密码文件
[root@node2 ~]# cryptsetup close westos 关闭加密磁盘
[root@node2 ~]# mkfs.xfs /dev/vdb1    格式化加密磁盘
mkfs.xfs: /dev/vdb1 appears to contain an existing filesystem (crypto_LUKS).
mkfs.xfs: Use the -f option to force overwrite.

[root@node2 ~]# mkfs.xfs /dev/vdb1 -f 加密此番格式化需要加-