第六周-day27-磁盘管理(下).png
磁盘分区步骤-截取自老男孩58期学员
先去虚拟机添加2块0.1G的磁盘，重启服务器后生效。
我们先去虚拟机添加2块0.1G的磁盘，要重启服务器
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
MBR分区表
二.分区类型
image.png
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
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
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
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
未完待续....
