磁盤及文件系統管理應用實例

磁盤及文件系統管理應用實例

• 1.創建一個10G的分區，并格式化為ext4文件系統
  • 要求其block大小為2048，預留空間百分比為2，卷標為MYDATA，默認掛載屬性包含acl
  • 掛載至/data/mydata目錄，要求掛載時禁止程序自動運行，且不更新文件的訪問時間戳

[root@master ~]# fdisk /dev/sdb
    Command (m for help): n   
    Partition type:
      p   primary (0 primary, 0 extended, 4 free)
      e   extended
    Select (default p): p
    Partition number (1-4, default 1): 1
    First sector (2048-41943039, default 2048):
    Using default value 2048
    Last sector, +sectors or +size{K,M,G} (2048-41943039, default 41943039): +10G
    Partition 1 of type Linux and of size 10 GiB is set    
    Command (m for help): w
    The partition table has been altered!

    [root@master ~]# mke2fs -t ext4 -b 2048 -m 2 -L MYDATA  /dev/sdb1
    [root@master ~]# tune2fs -o acl /dev/sdb1

    [root@master ~]# mount -o noexec,noatime /dev/sdb1 /data/mydata

• 2.創建一個大小為1G的swap分區，并創建好文件系統，并啟用之，寫一個腳本
  • 獲取并列出當前系統上的所有磁盤設備
  • 顯示每個磁盤設備上每個分區的相關的空間使用信息

[root@master ~]# fdisk /dev/sdb
    Command (m for help): n
    Partition type:
       p   primary (1 primary, 0 extended, 3 free)
       e   extended
    Select (default p): p
    Partition number (2-4, default 2): 2
    First sector (20973568-41943039, default 20973568):
    Using default value 20973568
    Last sector, +sectors or +size{K,M,G} (20973568-41943039, default 41943039): +1G
    Partition 2 of type Linux and of size 1 GiB is set
    Command (m for help): t
    Partition number (1,2, default 2): 2
    Hex code (type L to list all codes): L
    Hex code (type L to list all codes): 82
    Changed type of partition 'Linux' to 'Linux swap / Solaris'
    Command (m for help): w
    The partition table has been altered!

    [root@master ~]# mkswap -L SWAP /dev/sdb2
    [root@master ~]# swapon /dev/sdb2

    #!/bin/bash
    #
    disks=`fdisk -l|grep -o '^Disk /dev/[sh]d[a-z]'|cut -d' ' -f2`
    echo $disks
    for i in $disks;do
        fdisk -l $i
    done

• 3.總結RAID的各個級別及其組合方式和性能的不同
  RAID（冗余磁盤陣列）是將多塊磁盤當做一塊物理磁盤來使用，以達到容錯或者提高讀寫性能的優勢。按照 組織起來的工作方式的不同，我們可以將RAID分為不同的級別，其中常見的有RAID0、RAID1、RAID5、RAID10
  • RAID0
    • 俗稱條帶卷，實現將文件分成多個chunk后同時并行存儲到多個盤中。
    • 特性

      讀寫性能得到提升
      無冗余能力
      最少磁盤數為2
      可用空間為容量最小的磁盤*磁盤數

  • RAID1
    • 俗稱鏡像卷，在存儲數據的同時需要再復制一份存入另一個磁盤中。
    • 特性

      讀性能提升，寫性能下降
      有冗余能力
      最少磁盤數為2，偶數
      可用空間小于1/2

  • RAID5
    • 將文件分成多個chunk，兩兩chunk之間作異或運算，各盤輪流存儲校驗碼
    • 特點

      讀寫性能提升
      有冗余能力
      最少磁盤數為3
      可用空間為容量最小的磁盤*（磁盤數-1）

  • RAID10
    • 先兩兩做raid1，后將多組raid1組織成raid0
    • 特點

      讀寫性能提升
      有冗余能力
      最小磁盤數4
      可用空間為容量最小的磁盤*磁盤數/2

• 4.創建一個大小為10G的RAID1，要求有一個空閑盤，而且chunk大小為128k

  [root@master ~]# fdisk /dev/sdb
    Command (m for help): n
    Partition type:
       p   primary (0 primary, 0 extended, 4 free)
       e   extended
    Select (default p): p
    Partition number (1-4, default 1): 1
    First sector (2048-104857599, default 2048):
    Using default value 2048
    Last sector, +sectors or +size{K,M,G} (2048-104857599, default 104857599): +10G
    Partition 1 of type Linux and of size 10 GiB is set
    Command (m for help): n
    Partition type:
       p   primary (1 primary, 0 extended, 3 free)
       e   extended
    Select (default p): p
    Partition number (2-4, default 2): 2
    First sector (20973568-104857599, default 20973568): +10G
    Value out of range.
    First sector (20973568-104857599, default 20973568):
    Using default value 20973568
    Last sector, +sectors or +size{K,M,G} (20973568-104857599, default 104857599): +10G
    Partition 2 of type Linux and of size 10 GiB is set
    Command (m for help): n
    Partition type:
       p   primary (2 primary, 0 extended, 2 free)
       e   extended
    Select (default p): p
    Partition number (3,4, default 3): 3
    First sector (41945088-104857599, default 41945088):
    Using default value 41945088
    Last sector, +sectors or +size{K,M,G} (41945088-104857599, default 104857599): +10G
    Partition 3 of type Linux and of size 10 GiB is set
    Command (m for help): t
    Partition number (1-3, default 3): 1
    Hex code (type L to list all codes): fd
    Changed type of partition 'Linux' to 'Linux raid autodetect'
    Command (m for help): t
    Partition number (1-3, default 3): 2
    Hex code (type L to list all codes): fd
    Changed type of partition 'Linux' to 'Linux raid autodetect'
    Command (m for help): t
    Partition number (1-3, default 3): 3
    Hex code (type L to list all codes): fd
    Changed type of partition 'Linux' to 'Linux raid autodetect'
    Command (m for help): w
    The partition table has been altered!
  
    [root@master ~]# mdadm -C /dev/md0 -n 2 -c 128 -x 1 -l 1 -a yes /dev/sdb{1,2,3}
    mdadm: Defaulting to version 1.2 metadata
    mdadm: array /dev/md0 started.

• 5.創建一個大小為4G的RAID5設備，chunk大小為256k，格式化ext4文件系統，要求可開機自動掛載至/backup目錄，且不更新訪問時間戳，且支持acl功能
  “`

  [root@master ~]# fdisk /dev/sdb
    Command (m for help): n
    All primary partitions are in use
    Adding logical partition 5
    First sector (62918656-104857599, default 62918656):
    Using default value 62918656
    Last sector, +sectors or +size{K,M,G} (62918656-104857599, default 104857599): +2G
    Partition 5 of type Linux and of size 2 GiB is set
    Command (m for help): n
    All primary partitions are in use
    Adding logical partition 6
    First sector (67115008-104857599, default 67115008):
    Using default value 67115008
    Last sector, +sectors or +size{K,M,G} (67115008-104857599, default 104857599): +2G
    Partition 6 of type Linux and of size 2 GiB is set
    Command (m for help): n
    All primary partitions are in use
    Adding logical partition 7
    First sector (71311360-104857599, default 71311360):
    Using default value 71311360
    Last sector, +sectors or +size{K,M,G} (71311360-104857599, default 104857599): +2G
    Partition 7 of type Linux and of size 2 GiB is set
    Command (m for help): w
    The partition table has been altered!
  
    [root@master ~]# mdadm -C /dev/md1 -n 3 -c 256  -l 5 -a yes /dev/sdb{5,6,7}
    mdadm: Defaulting to version 1.2 metadata
    mdadm: array /dev/md1 started.
  
    [root@master ~]# mke2fs -t ext4  /dev/md1
    [root@master ~]# mkdir /backup
    [root@master ~]# mount -o auto /dev/md1 /backup