27-磁盘管理(下)
2019-05-26 本文已影响35人
杨丶子
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先去虚拟机添加2块0.1G的磁盘，重启服务器后生效。
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然后看一下添加的磁盘
fdisk -l |grep 'sd[a-z]'
[09:24 root@oldboy ~]# fdisk -l |grep 'sd[a-z]'
Disk /dev/sda: 21.5 GB, 21474836480 bytes, 41943040 sectors
/dev/sda1 * 2048 411647 204800 83 Linux
/dev/sda2 411648 2508799 1048576 82 Linux swap / Solaris
/dev/sda3 2508800 41943039 19717120 83 Linux
Disk /dev/sdb: 106 MB, 106954752 bytes, 208896 sectors
Disk /dev/sdc: 106 MB, 106954752 bytes, 208896 sectors
一.MBR
Master Boot Record 主引导记录
位置
磁盘的开头(0磁头 0磁道 1扇区)
0磁头 0磁道 1扇区 521字节前446字节
0头 0道 1扇区 521bytes
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二.分区类型
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主分区-primary
一个主分区要占用16个字节的分区表
在一个磁盘中最多4个主分区
一般必须要有
扩展分区-extended
磁盘最多只能有4个主分区
扩展分区无法直接使用
一个扩展分区也要占用16个字节的分区表
一个磁盘中只能创建一个扩展分区
数据必须放在扩展分区中的逻辑分区
逻辑分区-logical
需要先创建扩展分区
存放数据
三.分区命名规则
a.硬盘名字
1.sata/sas/scsi
/dev/sd??
按字母排列
第一块硬盘 /dev/sda
第二块硬盘 /dev/sdb2.云服务器(阿里云)
/dev/vda
/dev/vdb
b.分区名字※
主分区或扩展分区
1-4
/dev/sda1 /dev/sda4
逻辑分区
从5开始(>=5)
/dev/sda5 (第一个逻辑分区)
c.例子
第3块sata磁盘的第2个主分区 /dev/sdc2
第6块sas磁盘的第2个逻辑分区 /dedv/sdf6
四. fdisk分区和parted分区
| fdisk分区 | parted分区 | |
|---|---|---|
| 共同 | 磁盘分区 | 磁盘分区 |
| 区别 | 支持2TB以内硬盘 | 大于2TB磁盘 |
| 支持MBR分区表 | MBR GPT(支持更大的硬盘和更大的主分区) |
\ fdisk分区
1.创建2个分区 1个10MB的主分区 创建1个使用所有剩余空间的扩展 分区 1个20MB的逻辑分区
1.创建主分区
[15:35 root@oldboy ~]# fdisk /dev/sdb
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): n \\新建分区
Partition type:
p primary (0 primary, 0 extended, 4 free)
主分区p
e extended
扩展分区e
Select (default p):
默认就是p主分区
Partition number (1-4, default 1):
分区号 默认
First sector (2048-208895, default 2048):
磁盘分区中第一个扇区(从哪里开始) 默认的
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-208895, default 208895): +10M
磁盘分区中最后1个扇区
Partition 1 of type Linux and of size 10 MiB is set
创建了分区号是1的10MB的分区
Command (m for help): p
Disk /dev/sdb: 106 MB, 106954752 bytes, 208896 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: 0xa9b1cdab
Device Boot Start End Blocks Id System
/dev/sdb1 2048 22527 10240 83 Linux
2.创建扩展分区
Command (m for help): n \\新建分区
Partition type:
p primary (1 primary, 0 extended, 3 free)
e extended \\扩展分区
Select (default p): e
Partition number (2-4, default 2):
First sector (22528-208895, default 22528):
Using default value 22528
Last sector, +sectors or +size{K,M,G} (22528-208895, default 208895):
Using default value 208895
Partition 2 of type Extended and of size 91 MiB is set
Command (m for help): p
Disk /dev/sdb: 106 MB, 106954752 bytes, 208896 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: 0xe5935118
Device Boot Start End Blocks Id System
/dev/sdb1 2048 22527 10240 83 Linux
/dev/sdb2 22528 208895 93184 5 Extended
3.创建逻辑分区并保存退出
Command (m for help): n \\新建分区
Partition type:
p primary (1 primary, 1 extended, 2 free)
l logical (numbered from 5) //逻辑分区
Select (default p): l
Adding logical partition 5
First sector (24576-208895, default 24576):
Using default value 24576
Last sector, +sectors or +size{K,M,G} (24576-208895, default 208895): +20M
Partition 5 of type Linux and of size 20 MiB is set
Command (m for help): p
Disk /dev/sdb: 106 MB, 106954752 bytes, 208896 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: 0xe5935118
Device Boot Start End Blocks Id System
/dev/sdb1 2048 22527 10240 83 Linux
/dev/sdb2 22528 208895 93184 5 Extended
/dev/sdb5 24576 65535 20480 83 Linux
Command (m for help): w \\保存
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
4.查看
[10:42 root@oldboy ~]# ll /dev/sdb*
brw-rw---- 1 root disk 8, 16 Apr 30 10:42 /dev/sdb
brw-rw---- 1 root disk 8, 17 Apr 30 10:42 /dev/sdb1
brw-rw---- 1 root disk 8, 18 Apr 30 10:42 /dev/sdb2
brw-rw---- 1 root disk 8, 21 Apr 30 10:42 /dev/sdb5
如何删除分区:（接下题先把创建的删除掉）
Command (m for help): d \\按从后往前删除
2.创建1个使用磁盘所有容量的分区 并挂载到/mnt上(临时挂载点)
1.第一个里程碑-创建分区
[11:20 root@oldboy ~]# fdisk /dev/sdb
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): n \\新建分区
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p): p \\创建主分区
Partition number (1-4, default 1):
First sector (2048-208895, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-208895, default 208895):
Using default value 208895
Partition 1 of type Linux and of size 101 MiB is set
Command (m for help): p
Disk /dev/sdb: 106 MB, 106954752 bytes, 208896 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: 0xe5935118
Device Boot Start End Blocks Id System
/dev/sdb1 2048 208895 103424 83 Linux
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
2.第2个里程碑-格式化 创建文件系统
mkfs.xfs /dev/sdb1
[11:21 root@oldboy ~]# mkfs.xfs /dev/sdb1
meta-data=/dev/sdb1 isize=512 agcount=4, agsize=6464 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0, sparse=0
data = bsize=4096 blocks=25856, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal log bsize=4096 blocks=855, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
3.第3个里程碑-挂载
-
临时挂载 mount /dev/sdb1 /mnt
-
卸载 umount /mnt
[11:24 root@oldboy ~]# df -h \\查看已挂载的磁盘
Filesystem Size Used Avail Use% Mounted on
/dev/sda3 19G 2.3G 17G 13% /
devtmpfs 980M 0 980M 0% /dev
tmpfs 991M 0 991M 0% /dev/shm
tmpfs 991M 9.6M 981M 1% /run
tmpfs 991M 0 991M 0% /sys/fs/cgroup
/dev/sda1 197M 133M 64M 68% /boot
tmpfs 199M 0 199M 0% /run/user/0
[11:24 root@oldboy ~]# mount /dev/sdb1 /mnt/ \\挂载
[11:25 root@oldboy ~]# df -h \\再次查看
Filesystem Size Used Avail Use% Mounted on
/dev/sda3 19G 2.3G 17G 13% /
devtmpfs 980M 0 980M 0% /dev
tmpfs 991M 0 991M 0% /dev/shm
tmpfs 991M 9.6M 981M 1% /run
tmpfs 991M 0 991M 0% /sys/fs/cgroup
/dev/sda1 197M 133M 64M 68% /boot
tmpfs 199M 0 199M 0% /run/user/0
/dev/sdb1 98M 5.3M 93M 6% /mnt
挂载分区中的报错与排错
1.
Changes will remain in memory only, until you decide to write them.
你进行的修改默认存放在内存中,直到你决定保存这些修改的时候.
:wq
Be careful before using the write command.
保存之前小心点!
Device does not contain a recognized partition table
设备 没有 包含 磁盘分区表。
DPT= disk partition table 磁盘分区表
2.
mount /dev/sdb1 /mnt/
mount: /dev/sdb1 is already mounted or /mnt busy
这个分区已经安装或 繁忙
3.
mkfs.xfs /dev/sdb1
mkfs.xfs: /dev/sdb1 appears to contain an existing filesystem (ext4).
这个磁盘分区中 已经包含了1个文件系统（已经格式化过了）
mkfs.xfs: Use the -f option to force overwrite.
如果强制格式化覆盖使用-f
4.
[root@cuihua ~]# mount /dev/sdb1 /mnt
mount: /dev/sdb1 is write-protected, mounting read-only
写保护 安装只读
mount: unknown filesystem type '(null)'
未知的文件系统类型（没有格式化）
5.
[root@guanggege ~]# mount /dev/sdb1 /mnt/
mount: special device /dev/sdb1 does not exist
特殊文件（设备文件） 不存在
6.
[root@oldboyedu59 ~]# mkfs.xfs /dev/sdb1
mkfs.xfs: /dev/sdb1 contains a mounted filesystem
sdb1磁盘分区 包含 1个已经挂载的文件系统 （磁盘分区已经挂载）
7.
Invalid partition type `e'
"e"是无效的分区类型
4.第四个里程碑-永久挂载※
1./etc/rc.local
file /etc/rc.d/rc.local
/etc/rc.d/rc.local: Bourne-Again shell script, ASCII text executable
shell脚本,可执行
2./etc/fstab 开机自动挂载
cat /etc/fstab
UUID=8a44a07b-1b45-49c1-b6aa-c5ab81c717c8 / xfs defaults 0 0
UUID=2e59d872-2875-46bc-9e12-e59b9751ada1 /boot xfs defaults 0 0
UUID=13d82528-a2cc-484e-b468-9dfc25c36f5c swap swap defaults 0 0
第一列.UUID或设备名称
第二列.挂载点(入口)
第三列.文件系统类型
第四列.挂载参数
第五列.是否备份
第六列.是否开机自启动检查
blkid \\查询设备上所使用的文件系统类型、LABEL、UUID等信息
/dev/sda1: UUID="2e59d872-2875-46bc-9e12-e59b9751ada1" TYPE="xfs"
/dev/sda2: UUID="13d82528-a2cc-484e-b468-9dfc25c36f5c" TYPE="swap"
/dev/sda3: UUID="8a44a07b-1b45-49c1-b6aa-c5ab81c717c8" TYPE="xfs"
/dev/sdb1: UUID="b6242409-4b32-4ff3-a46e-7dab26695139" TYPE="xfs"
/dev/sr0: UUID="2018-11-25-23-54-16-00" LABEL="CentOS 7 x86_64" TYPE="iso9660" PTTYPE="dos"
为要挂载的磁盘添加一行
tail -1 /etc/fstab
/dev/sdb1 /date xfs defaults 0 0
CentOS7 默认的是xfs文件类型
CentOS6 5 默认 ext类型
\ parted(修改实时生效)
p print 显示磁盘信息
1.分区表
1.创建分区表parted /dev/sdc
[12:46 root@oldboy ~]# parted /dev/sdc
GNU Parted 3.1
Using /dev/sdc
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) p
Error: /dev/sdc: unrecognised disk label
Model: VMware, VMware Virtual S (scsi)
Disk /dev/sdc: 107MB
Sector size (logical/physical): 512B/512B
Partition Table: unknown
Disk Flags:
(parted) mktable gpt
(parted) p
Model: VMware, VMware Virtual S (scsi)
Disk /dev/sdc: 107MB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:
Number Start End Size File system Name Flags
- mkpart primary指定大小
(parted) mkpart primary 0 10
Warning: The resulting partition is not properly aligned for best
performance.
Ignore/Cancel? i
(parted)
3.查看创建是否成功
(parted) p
Model: VMware, VMware Virtual S (scsi)
Disk /dev/sdc: 107MB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags:
Number Start End Size File system Name Flags
1 17.4kB 10.0MB 9983kB primary
4.退出
(parted) q
Information: You may need to update /etc/fstab.
5.显示分区信息
ll /dev/sdc*
brw-rw---- 1 root disk 8, 32 Apr 30 12:51 /dev/sdc
brw-rw---- 1 root disk 8, 33 Apr 30 12:51 /dev/sdc1
