第一周周末作业_蒋雷雷 - 《运维训练营》

1 做5个分区，其中3个分区是1GB(假定a,b,c是1GB空间)，另外2个分区是2GB（假定d,e是2GB空间）。

gauss@gauss-XPS-15-9570:~$ sudo parted /dev/sda
[sudo] gauss 的密码：
GNU Parted 3.2
使用 /dev/sda
欢迎使用 GNU Parted! 输入 'help'可获得命令列表.
(parted) mklabel
新的磁盘标签类型？ gpt
警告: The existing disk label on /dev/sda will be destroyed and all data on this
disk will be lost. Do you want to continue?
是/Yes/否/No? yes
(parted) mkpart primary ext4 0G 1G
(parted) mkpart primary ext4 1G 2G
(parted) mkpart primary ext4 2G 3G
(parted) mkpart primary ext4 3G 5G
(parted) mkpart primary ext4 5G 7G
(parted) quit
信息: You may need to update /etc/fstab.
gauss@gauss-XPS-15-9570:~$ sudo fdisk -l /dev/sda
Disk /dev/sda：7.2 GiB，7776239616 字节，15187968 个扇区
单元：扇区 / 1 * 512 = 512 字节
扇区大小(逻辑/物理)：512 字节 / 512 字节
I/O 大小(最小/最佳)：512 字节 / 512 字节
磁盘标签类型：gpt
磁盘标识符：5FA5E1BB-5C7B-4FAE-9098-077B7B74C485
设备          起点     末尾    扇区  大小 类型
/dev/sda1     2048  1953791 1951744  953M Linux 文件系统
/dev/sda2  1953792  3905535 1951744  953M Linux 文件系统
/dev/sda3  3905536  5859327 1953792  954M Linux 文件系统
/dev/sda4  5859328  9764863 3905536  1.9G Linux 文件系统
/dev/sda5  9764864 13672447 3907584  1.9G Linux 文件系统
gauss@gauss-XPS-15-9570:~$ sudo mdadm -Cv /dev/md0 -ayes -l5 -n3 -x1 /dev/sda[1-4]
mdadm: layout defaults to left-symmetric
mdadm: layout defaults to left-symmetric
mdadm: chunk size defaults to 512K
mdadm: /dev/sda1 appears to contain an ext2fs file system
       size=975872K  mtime=Thu Jan  1 08:00:00 1970
mdadm: /dev/sda1 appears to be part of a raid array:
       level=raid5 devices=5 ctime=Sat Mar 28 22:06:24 2020
mdadm: /dev/sda2 appears to contain an ext2fs file system
       size=975872K  mtime=Sun Mar 29 13:08:07 2020
mdadm: /dev/sda2 appears to be part of a raid array:
       level=raid5 devices=5 ctime=Sat Mar 28 22:06:24 2020
mdadm: /dev/sda3 appears to contain an ext2fs file system
       size=976896K  mtime=Thu Jan  1 08:00:00 1970
mdadm: /dev/sda3 appears to be part of a raid array:
       level=raid5 devices=5 ctime=Sat Mar 28 22:06:24 2020
mdadm: /dev/sda4 appears to contain an ext2fs file system
       size=976896K  mtime=Thu Jan  1 08:00:00 1970
mdadm: /dev/sda4 appears to be part of a raid array:
       level=raid5 devices=5 ctime=Sat Mar 28 22:06:24 2020
mdadm: size set to 973824K
mdadm: largest drive (/dev/sda4) exceeds size (973824K) by more than 1%
Continue creating array? y
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.
gauss@gauss-XPS-15-9570:~$ sudo cat /proc/mdstat
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] 
md0 : active raid5 sda3[4] sda4[3](S) sda2[1] sda1[0]
      1947648 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/3] [UUU]
unused devices: <none>
gauss@gauss-XPS-15-9570:~$ sudo df -h
文件系统        容量  已用  可用 已用% 挂载点
/dev/md0        1.8G  5.6M  1.7G    1% /data
gauss@gauss-XPS-15-9570:~$ sudo mdadm --detail /dev/md0
/dev/md0:
           Version : 1.2
     Creation Time : Sun Mar 29 15:51:26 2020
        Raid Level : raid5
        Array Size : 1947648 (1902.00 MiB 1994.39 MB)
     Used Dev Size : 973824 (951.00 MiB 997.20 MB)
      Raid Devices : 3
     Total Devices : 4
       Persistence : Superblock is persistent
       Update Time : Sun Mar 29 16:03:00 2020
             State : active
    Active Devices : 3
   Working Devices : 4
    Failed Devices : 0
     Spare Devices : 1
            Layout : left-symmetric
        Chunk Size : 512K
Consistency Policy : resync
              Name : gauss-XPS-15-9570:0  (local to host gauss-XPS-15-9570)
              UUID : 93d40a03:345dd2b4:577558ad:b3bca090
            Events : 19
    Number   Major   Minor   RaidDevice State
       0       8        1        0      active sync   /dev/sda1
       1       8        2        1      active sync   /dev/sda2
       4       8        3        2      active sync   /dev/sda3
       3       8        4        -      spare   /dev/sda4
# 将 /dev/sda3 宣布为坏盘并移除，/dev/sda4能顶上来
gauss@gauss-XPS-15-9570:~$ sudo df -h
文件系统        容量  已用  可用 已用% 挂载点
/dev/md0        1.8G  5.6M  1.7G    1% /data
gauss@gauss-XPS-15-9570:~$ sudo cat /proc/mdstat
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]
md0 : active raid5 sda3[4](F) sda4[3] sda2[1] sda1[0]
      1947648 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/3] [UUU]
unused devices: <none>
# 重新组盘
gauss@gauss-XPS-15-9570:~$ sudo umount /dev/md0
gauss@gauss-XPS-15-9570:~$ sudo mdadm -S /dev/md0
mdadm: stopped /dev/md0
gauss@gauss-XPS-15-9570:~$ sudo mdadm -C /dev/md0 -ayes -l5 -n3 -x1 /dev/sda[2,3,4,1]
mdadm: /dev/sda1 appears to contain an ext2fs file system
       size=975872K  mtime=Thu Jan  1 08:00:00 1970
mdadm: /dev/sda1 appears to be part of a raid array:
       level=raid5 devices=3 ctime=Sun Mar 29 15:51:26 2020
mdadm: /dev/sda2 appears to contain an ext2fs file system
       size=975872K  mtime=Sun Mar 29 13:08:07 2020
mdadm: /dev/sda2 appears to be part of a raid array:
       level=raid5 devices=3 ctime=Sun Mar 29 15:51:26 2020
mdadm: /dev/sda3 appears to contain an ext2fs file system
       size=976896K  mtime=Thu Jan  1 08:00:00 1970
mdadm: /dev/sda3 appears to be part of a raid array:
       level=raid5 devices=3 ctime=Sun Mar 29 15:51:26 2020
mdadm: /dev/sda4 appears to contain an ext2fs file system
       size=976896K  mtime=Thu Jan  1 08:00:00 1970
mdadm: /dev/sda4 appears to be part of a raid array:
       level=raid5 devices=3 ctime=Sun Mar 29 15:51:26 2020
mdadm: largest drive (/dev/sda4) exceeds size (973824K) by more than 1%
Continue creating array? y
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.
gauss@gauss-XPS-15-9570:~$ sudo mdadm --detail /dev/md0
/dev/md0:
           Version : 1.2
     Creation Time : Sun Mar 29 16:23:21 2020
        Raid Level : raid5
        Array Size : 1947648 (1902.00 MiB 1994.39 MB)
     Used Dev Size : 973824 (951.00 MiB 997.20 MB)
      Raid Devices : 3
     Total Devices : 4
       Persistence : Superblock is persistent
       Update Time : Sun Mar 29 16:27:07 2020
             State : clean 
    Active Devices : 3
   Working Devices : 4
    Failed Devices : 0
     Spare Devices : 1
            Layout : left-symmetric
        Chunk Size : 512K
Consistency Policy : resync
              Name : gauss-XPS-15-9570:0  (local to host gauss-XPS-15-9570)
              UUID : 4044f0db:33189482:6a3c7cc4:b1e2de63
            Events : 18
    Number   Major   Minor   RaidDevice State
       0       8        1        0      active sync   /dev/sda1
       1       8        2        1      active sync   /dev/sda2
       4       8        3        2      active sync   /dev/sda3
       3       8        4        -      spare   /dev/sda4

1）如果用abcd 组成一块raid盘组，abc是raid盘，d是热备盘，组好后空间是多大？[1.8G]把c盘宣布为坏盘，并且移除，看看d是否能顶上来，顶上来的话，空间是多大？[1.8G]
2）如果用abcd 组成一块raid盘组， bcd是raid盘，a是热备盘，组好后空间是多大？[1.8G]

2 请问下面的过程是否能正常恢复出raid盘组

gauss@gauss-XPS-15-9570:~$ sudo mdadm -C /dev/md0 --level=5 --raid-devices=3 /dev/sda1 /dev/sda2 /dev/sda3
mdadm: /dev/sda1 appears to contain an ext2fs file system
       size=975872K  mtime=Thu Jan  1 08:00:00 1970
mdadm: /dev/sda1 appears to be part of a raid array:
       level=raid5 devices=3 ctime=Sun Mar 29 16:23:21 2020
mdadm: /dev/sda2 appears to contain an ext2fs file system
       size=975872K  mtime=Sun Mar 29 13:08:07 2020
mdadm: /dev/sda2 appears to be part of a raid array:
       level=raid5 devices=3 ctime=Sun Mar 29 16:23:21 2020
mdadm: /dev/sda3 appears to contain an ext2fs file system
       size=976896K  mtime=Thu Jan  1 08:00:00 1970
mdadm: /dev/sda3 appears to be part of a raid array:
       level=raid5 devices=3 ctime=Sun Mar 29 16:23:21 2020
Continue creating array? y
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.

gauss@gauss-XPS-15-9570:~$ sudo mdadm -S /dev/md0
mdadm: stopped /dev/md0
gauss@gauss-XPS-15-9570:~$ sudo mdadm -A /dev/md1 /dev/sda3 /dev/sda2 /dev/sda1
mdadm: /dev/md1 has been started with 3 drives.
gauss@gauss-XPS-15-9570:~$ sudo cat /proc/mdstat
Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10] 
md1 : active raid5 sda1[0] sda3[3] sda2[1]
      1947648 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/3] [UUU]

unused devices: <none>

gauss@gauss-XPS-15-9570:/$ sudo mount /dev/md1 /data
gauss@gauss-XPS-15-9570:/$ ls /data
created_in_md0.txt  lost+found

mdadm -C /dev/md0 —level=5 —raid-devices=3 /dev/vdb1 /dev/vdb2 /dev/vdb3
mdadm -S /dev/md0
mdadm -A /dev/md1 /dev/vdb3 /dev/vdb2 /dev/vdb1 (注意这里和创建的设备号不同，创建的时候叫md0，此时是md1；创建的时候是1，2，3;现在是3，2，1) ，这个命令能把原来的盘恢复出来嘛？请试试看[能]

3 如果创建了一个raid盘组，并mount在/data 目录上，但是如果想让机器每次启动后就自动就mount到 /data/ 盘上，写一段命令完成这个工作

gauss@gauss-XPS-15-9570:~$ sudo umount /dev/md0
gauss@gauss-XPS-15-9570:~$ sudo mount /dev/md0 /data
gauss@gauss-XPS-15-9570:~$ sudo blkid /dev/md0
/dev/md0: UUID="aa91fb28-821b-4360-8f7e-39ace21d3852" TYPE="ext4"

# 此处省略Vim修改 /etc/fstab 文件过程，以下是修改后的结果。

gauss@gauss-XPS-15-9570:~$ sudo 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/nvme0n1p2 during installation
UUID=3c2e90aa-5284-4b9d-a55d-29fa57926d3d /               ext4    errors=remount-ro 0       1
# /boot/efi was on /dev/nvme0n1p1 during installation
UUID=AC2D-DC2E  /boot/efi       vfat    umask=0077      0       1
/swapfile                                 none            swap    sw              0       0
UUID="aa91fb28-821b-4360-8f7e-39ace21d3852" /data ext4 defaults 0 0