CentOS 组建Raid5

前言

买了个USB硬盘柜，本身不支持RAID，想做RAID用。
试了windows11：做存储池时一拷东西就掉盘
WindowsServer 2016：无法做存储池（硬盘柜里的所有硬盘序列号都一样，磁盘管理里也无法转换动态分区）
黑群晖：稳定性不是很好

最后决定使用linux做个Raid，最后samba挂到其他地方用。

设备

N3540的矿难小主机（主要性能需求不大，自己有个闲置的，而且功耗特别低，不用风扇也不热）
ORICO硬盘柜（闲鱼淘的二手，300块五盘位）
五块硬盘（选了6T监控盘，功耗小点，自己对速度需求也不大，而且都走USB了也没啥速度）

组建Raid5

CentOS安装好后查看硬盘状态

[root@localhost ~]# lsblk
NAME            MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda               8:0    0 238.5G  0 disk 
├─sda1            8:1    0   200M  0 part /boot/efi
├─sda2            8:2    0     1G  0 part /boot
└─sda3            8:3    0 237.3G  0 part 
  ├─centos-root 253:0    0    50G  0 lvm  /
  ├─centos-swap 253:1    0   7.8G  0 lvm  [SWAP]
  └─centos-home 253:2    0 179.5G  0 lvm  /home
sdb               8:16   0   5.5T  0 disk 
sdc               8:32   0   5.5T  0 disk 
sdd               8:48   0   5.5T  0 disk 
sde               8:64   0   5.5T  0 disk 
sdf               8:80   0   5.5T  0 disk 

五块盘都认出来了，sdb-sdf，容量也正确

使用mdadm创建raid

[root@localhost ~]# sudo mdadm --create --verbose /dev/md0 --level=5 --raid-devices=5 /dev/sdb /dev/sdc /dev/sdd /dev/sde /dev/sdf
mdadm: layout defaults to left-symmetric
mdadm: layout defaults to left-symmetric
mdadm: chunk size defaults to 512K
mdadm: partition table exists on /dev/sdb
mdadm: partition table exists on /dev/sdb but will be lost or
       meaningless after creating array
mdadm: partition table exists on /dev/sdc
mdadm: partition table exists on /dev/sdc but will be lost or
       meaningless after creating array
mdadm: partition table exists on /dev/sdd
mdadm: partition table exists on /dev/sdd but will be lost or
       meaningless after creating array
mdadm: partition table exists on /dev/sde
mdadm: partition table exists on /dev/sde but will be lost or
       meaningless after creating array
mdadm: partition table exists on /dev/sdf
mdadm: partition table exists on /dev/sdf but will be lost or
       meaningless after creating array
mdadm: size set to 5860390400K
mdadm: automatically enabling write-intent bitmap on large array
Continue creating array? 
Continue creating array? (y/n) y
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.

查看RAID状态

[root@localhost ~]# sudo mdadm --detail /dev/md0
/dev/md0:
           Version : 1.2
     Creation Time : Fri Jul  5 07:27:37 2024
        Raid Level : raid5
        Array Size : 23441561600 (22355.62 GiB 24004.16 GB)
     Used Dev Size : 5860390400 (5588.90 GiB 6001.04 GB)
      Raid Devices : 5
     Total Devices : 5
       Persistence : Superblock is persistent

     Intent Bitmap : Internal

       Update Time : Fri Jul  5 07:27:43 2024
             State : clean, degraded, recovering 
    Active Devices : 4
   Working Devices : 5
    Failed Devices : 0
     Spare Devices : 1

            Layout : left-symmetric
        Chunk Size : 512K

Consistency Policy : bitmap

    Rebuild Status : 0% complete

              Name : localhost.localdomain:0  (local to host localhost.localdomain)
              UUID : 3302b9f5:f38071b2:dc13cf9b:5356f797
            Events : 2

    Number   Major   Minor   RaidDevice State
       0       8       16        0      active sync   /dev/sdb
       1       8       32        1      active sync   /dev/sdc
       2       8       48        2      active sync   /dev/sdd
       3       8       64        3      active sync   /dev/sde
       5       8       80        4      spare rebuilding   /dev/sdf

格式化

[root@localhost ~]# sudo mkfs.ext4 /dev/md0
mke2fs 1.42.9 (28-Dec-2013)
文件系统标签=
OS type: Linux
块大小=4096 (log=2)
分块大小=4096 (log=2)
Stride=128 blocks, Stripe width=512 blocks
366274560 inodes, 5860390400 blocks
293019520 blocks (5.00%) reserved for the super user
第一个数据块=0
178845 block groups
32768 blocks per group, 32768 fragments per group
2048 inodes per group
Superblock backups stored on blocks: 
        32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208, 
        4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968, 
        102400000, 214990848, 512000000, 550731776, 644972544, 1934917632, 
        2560000000, 3855122432, 5804752896

Allocating group tables: 完成                            
正在写入inode表: 完成                            
Creating journal (32768 blocks): 完成
Writing superblocks and filesystem accounting information:           
完成

格式化完之后就可以挂载了,创建/mnt/raid5目录，将md0挂在里面

[root@localhost ~]# sudo mkdir /mnt/raid5
[root@localhost ~]# sudo mount /dev/md0 /mnt/raid5

这时候可以测试存放数据，测试完成后需要将虚拟磁盘添加到fstab开机挂载

查看UUID

[root@localhost ~]# sudo blkid /dev/md0
/dev/md0: UUID="7af86e80-718d-4cc5-8556-a0c58c6bb760" TYPE="ext4" 

记好UUID后编辑/etc/fstab,添加一行

UUID=7af86e80-718d-4cc5-8556-a0c58c6bb760 /mnt/raid5 ext4 defaults 0 2

保存RAID记录

[root@localhost ~]# sudo mdadm --detail --scan | sudo tee -a /etc/mdadm.conf
ARRAY /dev/md0 metadata=1.2 spares=1 name=localhost.localdomain:0 UUID=3302b9f5:f38071b2:dc13cf9b:5356f797

保存完后重启测试，看看是否可以自动挂载，存取数据是否正常

速度测试

[root@localhost raid5]# dd if=/dev/zero of=/mnt/raid5/test bs=1M count=1024
记录了1024+0 的读入
记录了1024+0 的写出
1073741824字节(1.1 GB)已复制，2.93325 秒，366 MB/秒