Linux系统的磁盘管理
一、环境介绍
1.Linux系统版本
[root@node1 ~]# cat /etc/redhat-release
Red Hat Enterprise Linux release 8.0 (Ootpa)
[root@node1 ~]#
2.系统磁盘情况
[root@node1 ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 20G 0 disk
sdb 8:16 0 20G 0 disk
sdc 8:32 0 20G 0 disk
sdd 8:48 0 20G 0 disk
sr0 11:0 1 1024M 0 rom
nvme0n1 259:0 0 20G 0 disk
├─nvme0n1p1 259:1 0 500M 0 part /boot
├─nvme0n1p2 259:2 0 2G 0 part [SWAP]
└─nvme0n1p3 259:3 0 17.5G 0 part /
[root@node1 ~]#
二、磁盘介绍
1.磁盘分区理解
将磁盘划分为逻辑存储单元，这些单元成为分区，对不同的分区执行不同的功能。
2.MBR分区方案
分区类型：主分区、扩展分区和逻辑分区
限制：最多有4个主分区，磁盘最大为2TB
MBR:主引导记录（MBR），也被称为主引导扇区，是计算机开机以后访问硬盘时所必须要读取的第一个扇区。
MBR（主引导扇区）+主分区1+主分区2+主分区3+扩展分区4（包括逻辑分区5+逻辑分区6+未使用空间）
2.GPT分区分区方案
GPT：GPT使用全局唯一表示符GUID来识别磁盘和分区
GPT提供分区表备份功能，主GPT位于磁盘头部，备份的GPT位于磁盘尾部。
限制：最多有128个分区，磁盘最大为8ZiB
主GPT+sda1+sda2+sda3+…+备GPT
三、分区工具fidsk使用
1.查看磁盘和分区信息
fdisk工具分区为MBR分区
[root@node1 ~]# fdisk -l
Disk /dev/nvme0n1: 20 GiB, 21474836480 bytes, 41943040 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: 0x9bbd6bb3
Device Boot Start End Sectors Size Id Type
/dev/nvme0n1p1 * 2048 1026047 1024000 500M 83 Linux
/dev/nvme0n1p2 1026048 5220351 4194304 2G 82 Linux swap / Solaris
/dev/nvme0n1p3 5220352 41940991 36720640 17.5G 83 Linux
Disk /dev/sda: 20 GiB, 21474836480 bytes, 41943040 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 /dev/sdb: 20 GiB, 21474836480 bytes, 41943040 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 /dev/sdc: 20 GiB, 21474836480 bytes, 41943040 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 /dev/sdd: 20 GiB, 21474836480 bytes, 41943040 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
2.查看指定设备信息
[root@node1 ~]# fdisk -l /dev/nvme0n1
Disk /dev/nvme0n1: 20 GiB, 21474836480 bytes, 41943040 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: 0x9bbd6bb3
Device Boot Start End Sectors Size Id Type
/dev/nvme0n1p1 * 2048 1026047 1024000 500M 83 Linux
/dev/nvme0n1p2 1026048 5220351 4194304 2G 82 Linux swap / Solaris
/dev/nvme0n1p3 5220352 41940991 36720640 17.5G 83 Linux
[root@node1 ~]# fdisk -l /dev/sda
Disk /dev/sda: 20 GiB, 21474836480 bytes, 41943040 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
[root@node1 ~]#
3.对新磁盘进行分区
[root@node1 ~]#
[root@node1 ~]# fdisk /dev/sda
Welcome to fdisk (util-linux 2.32.1).
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.
Created a new DOS disklabel with disk identifier 0x962ab0e1.
Command (m for help): n
Partition type
p primary (0 primary, 0 extended, 4 free)
e extended (container for logical partitions)
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-41943039, default 2048): +5G
Value out of range.
First sector (2048-41943039, default 2048):
Last sector, +sectors or +size{K,M,G,T,P} (2048-41943039, default 41943039): +5G
Created a new partition 1 of type 'Linux' and of size 5 GiB.
Command (m for help): p
Disk /dev/sda: 20 GiB, 21474836480 bytes, 41943040 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: 0x962ab0e1
Device Boot Start End Sectors Size Id Type
/dev/sda1 2048 10487807 10485760 5G 83 Linux
Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.
[root@node1 ~]#
4.格式化文件系统
[root@node1 ~]# mkfs.xfs /dev/sda1
meta-data=/dev/sda1 isize=512 agcount=4, agsize=327680 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=1, sparse=1, rmapbt=0
= reflink=1
data = bsize=4096 blocks=1310720, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0, ftype=1
log =internal log bsize=4096 blocks=2560, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
[root@node1 ~]#
四、gdisk工具使用
1.gdisk进行分区
gdisk工具主要为gpt分区
[root@node1 ~]# gdisk /dev/sdb
GPT fdisk (gdisk) version 1.0.3
Partition table scan:
MBR: not present
BSD: not present
APM: not present
GPT: not present
Creating new GPT entries.
Command (? for help): n
Partition number (1-128, default 1):
First sector (34-41943006, default = 2048) or {+-}size{KMGTP}:
Last sector (2048-41943006, default = 41943006) or {+-}size{KMGTP}: +6G
Current type is 'Linux filesystem'
Hex code or GUID (L to show codes, Enter = 8300):
Changed type of partition to 'Linux filesystem'
Command (? for help): w
Final checks complete. About to write GPT data. THIS WILL OVERWRITE EXISTING
PARTITIONS!!
Do you want to proceed? (Y/N): y
OK; writing new GUID partition table (GPT) to /dev/sdb.
The operation has completed successfully.
[root@node1 ~]# lsblk
2.查看sdb磁盘下分区情况
[root@node1 ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 20G 0 disk
└─sda1 8:1 0 5G 0 part
sdb 8:16 0 20G 0 disk
└─sdb1 8:17 0 6G 0 part
sdc 8:32 0 20G 0 disk
sdd 8:48 0 20G 0 disk
sr0 11:0 1 1024M 0 rom
nvme0n1 259:0 0 20G 0 disk
├─nvme0n1p1 259:1 0 500M 0 part /boot
├─nvme0n1p2 259:2 0 2G 0 part [SWAP]
└─nvme0n1p3 259:3 0 17.5G 0 part /
[root@node1 ~]#
五、挂载文件系统
[root@node1 ~]#
[root@node1 ~]# mkdir /mnt/test
[root@node1 ~]# mount /dev/sda1 /mnt/test/
[root@node1 ~]# df -h
Filesystem Size Used Avail Use% Mounted on
devtmpfs 970M 0 970M 0% /dev
tmpfs 984M 0 984M 0% /dev/shm
tmpfs 984M 9.3M 974M 1% /run
tmpfs 984M 0 984M 0% /sys/fs/cgroup
/dev/nvme0n1p3 18G 11G 7.3G 59% /
/dev/nvme0n1p1 495M 140M 356M 29% /boot
overlay 18G 11G 7.3G 59% /var/lib/docker/overlay2/3851b60316c4c9b3d888c4e6133589bee2882b3e231cf2c4d9ff42eca7a4a390/merged
overlay 18G 11G 7.3G 59% /var/lib/docker/overlay2/8c7e59c24a0b2648c82f41eeddba522e58e06c6809ff702f641f6377b60e8d1f/merged
tmpfs 197M 4.0K 197M 1% /run/user/0
/dev/sda1 5.0G 68M 5.0G 2% /mnt/test
[root@node1 ~]#
六、查看文件系统信息
[root@node1 ~]# lsblk -fs
NAME FSTYPE LABEL UUID MOUNTPOINT
sda1 xfs 7060a61e-a422-4d5e-b37d-f6998463dddd /mnt/test
└─sda
sdb1
└─sdb
sdc
sdd
sr0
nvme0n1p1 xfs 525a30a7-d484-4ed5-9f38-f827f54e29ff /boot
└─nvme0n1
nvme0n1p2 swap e6cf8733-5eec-4942-9429-c3e9087b6ff0 [SWAP]
└─nvme0n1
nvme0n1p3 xfs b7190d80-906f-4b9d-9ab4-5a503ecaea2c /
└─nvme0n1
[root@node1 ~]#
七、fsck文件系统修复工具
1.fsck使用语法
语法
fsck [-sACVRP] [-t fstype] [--] [fsck-options] filesys [...]
参数 ：
filesys ： device 名称(eg./dev/sda1)，mount 点 (eg. / 或 /usr)
-t : 给定档案系统的型式，若在 /etc/fstab 中已有定义或 kernel 本身已支援的则不需加上此参数
-s : 依序一个一个地执行 fsck 的指令来检查
-A : 对/etc/fstab 中所有列出来的 partition 做检查
-C : 显示完整的检查进度
-d : 列印 e2fsck 的 debug 结果
-p : 同时有 -A 条件时，同时有多个 fsck 的检查一起执行
-R : 同时有 -A 条件时，省略 / 不检查
-V : 详细显示模式
-a : 如果检查有错则自动修复
-r : 如果检查有错则由使用者回答是否修复
2.修复ext4格式文件系统
[root@node1 ~]# fsck -t ext4 /dev/sda2
fsck from util-linux 2.32.1
e2fsck 1.44.3 (10-July-2018)
/dev/sda2: clean, 11/327680 files, 42078/1310720 blocks
[root@node1 ~]#
3.fsck自动修复
[root@node1 ~]# fsck -a /dev/sda2
fsck from util-linux 2.32.1
/dev/sda2: clean, 11/327680 files, 42078/1310720 blocks
[root@node1 ~]#
4.e2fsck自动修复
[root@node1 ~]# e2fsck -y /dev/sda2
e2fsck 1.44.3 (10-July-2018)
/dev/sda2: clean, 11/327680 files, 42078/1310720 blocks
[root@node1 ~]#
八、xfs_repair文件系统修复工具
[root@node1 ~]# xfs_repair /dev/sda1
Phase 1 - find and verify superblock...
Phase 2 - using internal log
- zero log...
- scan filesystem freespace and inode maps...
- found root inode chunk
Phase 3 - for each AG...
- scan and clear agi unlinked lists...
- process known inodes and perform inode discovery...
- agno = 0
- agno = 1
- agno = 2
- agno = 3
- process newly discovered inodes...
Phase 4 - check for duplicate blocks...
- setting up duplicate extent list...
- check for inodes claiming duplicate blocks...
- agno = 0
- agno = 1
- agno = 2
- agno = 3
Phase 5 - rebuild AG headers and trees...
- reset superblock...
Phase 6 - check inode connectivity...
- resetting contents of realtime bitmap and summary inodes
- traversing filesystem ...
- traversal finished ...
- moving disconnected inodes to lost+found ...
Phase 7 - verify and correct link counts...
done
[root@node1 ~]#
