• 企业400电话
  • 微网小程序
  • AI电话机器人
  • 电商代运营
  • 全 部 栏 目

    企业400电话 网络优化推广 AI电话机器人 呼叫中心 网站建设 商标✡知产 微网小程序 电商运营 彩铃•短信 增值拓展业务
    详解基于Linux的LVM无缝磁盘水平扩容

    环境

    名称 属性
    CPU x5650
    内存 4G
    磁盘 20G+4TB

     

    这时候,我们假设服务器已经有如下东西:

    软件安装与信息查看

    首先查看软件是否安装:

    [root@Candy ~]# rpm -qa | grep lvm
    lvm2-libs-2.02.118-2.el6.x86_64
    lvm2-2.02.118-2.el6.x86_64
    [root@Candy ~]# lv
    lvchange   lvextend   lvmdiskscan lvmsar    lvresize
    lvconvert  lvm     lvmdump   lvreduce   lvs
    lvcreate   lvmchange  lvmetad   lvremove   lvscan
    lvdisplay  lvmconf   lvmsadc   lvrename
    [root@Candy ~]# rpm -qa | grep parted
    parted-2.1-29.el6.x86_64

    软件准备好后顺便查看下 VM 硬件:

    [root@Candy ~]# df -h
    Filesystem      Size Used Avail Use% Mounted on
    /dev/mapper/vg_candy-root
               7.3G 231M 6.7G  4% /
    tmpfs         1.9G   0 1.9G  0% /dev/shm
    /dev/sda1       477M  30M 422M  7% /boot
    /dev/mapper/vg_candy-home
               3.9G 8.0M 3.7G  1% /home
    /dev/mapper/vg_candy-usr
               3.9G 382M 3.3G 11% /usr
    /dev/mapper/vg_candy-var
               3.9G  63M 3.6G  2% /var
    [root@Candy ~]# fdisk -l
    Disk /dev/sda: 21.5 GB, 21474836480 bytes
    255 heads, 63 sectors/track, 2610 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x0006e71c
      Device Boot   Start     End   Blocks  Id System
    /dev/sda1  *      1     64   512000  83 Linux
    Partition 1 does not end on cylinder boundary.
    /dev/sda2       64    2611  20458496  8e Linux LVM
    Disk /dev/sdb: 4398.0 GB, 4398046511104 bytes
    255 heads, 63 sectors/track, 534698 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x00000000
    Disk /dev/mapper/vg_candy-root: 8061 MB, 8061452288 bytes
    255 heads, 63 sectors/track, 980 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x00000000
    Disk /dev/mapper/vg_candy-usr: 4294 MB, 4294967296 bytes
    255 heads, 63 sectors/track, 522 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x00000000
    Disk /dev/mapper/vg_candy-var: 4294 MB, 4294967296 bytes
    255 heads, 63 sectors/track, 522 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x00000000
    Disk /dev/mapper/vg_candy-home: 4294 MB, 4294967296 bytes
    255 heads, 63 sectors/track, 522 cylinders
    Units = cylinders of 16065 * 512 = 8225280 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disk identifier: 0x00000000
    [root@Candy ~]# ls /dev/sd*
    /dev/sda /dev/sda1 /dev/sda2 /dev/sdb

    这时候我们看到,Centos 已经知道有个sdb的盘了,但是没挂载与分区。

    使用Parted进行扩容前的分区

    现在假设除了/boot 其余分区都满了! 我们需要先进行分区,将4T的硬盘用上(/dev/sdb).

    [root@Candy ~]# parted /dev/sdb
    GNU Parted 2.1
    使用 /dev/sdb
    Welcome to GNU Parted! Type 'help' to view a list of commands.
    (parted) mklabel
    新的磁盘标签类型? gpt
    (parted) mkpart
    分区名称? []?
    文件系统类型? [ext2]? ext4
    起始点? 0T
    结束点? 4T
    (parted) p
    Model: VMware, VMware Virtual S (scsi)
    Disk /dev/sdb: 4398GB
    Sector size (logical/physical): 512B/512B
    Partition Table: gpt
    Number Start  End   Size  File system Name 标志
     1   1049kB 4398GB 4398GB
    (parted)set 1 lvm on
    (parted)p
    Model: VMware, VMware Virtual S (scsi)
    Disk /dev/sdb: 4398GB
    Sector size (logical/physical): 512B/512B
    Partition Table: gpt
    Number Start  End   Size  File system Name 标志
    1   1049kB 4398GB 4398GB           lvm
    (parted)q
    [root@Candy ~]# ls /dev/sd*
    /dev/sda /dev/sda1 /dev/sda2 /dev/sdb /dev/sdb1

    现在让我们来解释一下操作:

    1. mklabel将磁盘转换为gpt分区,因为MBR分区无法支持TB级硬盘(具体请自行查阅,parted当然也支持TB级以下的操作)
    2. mkpart将转换好的gpt磁盘进行分区,需要提供文件系统类型、开始点、结束点。
    3. 输入p 打印出刚才才做后生成的分区。
    4. set 1 lvm on 是将num为1的分区,tager设置为LVM ,这样才能添加到vm卷组里

    下一步,我们查看我们的LVM组名叫什么:

    [root@Candy ~]# vgs
     VG    #PV #LV #SN Attr  VSize VFree
     vg_candy  1  4  0 wz--n- 19.51g  0
     
    [root@Candy ~]# vgdisplay
     --- Volume group ---
     VG Name        vg_candy
     System ID
     Format        lvm2
     Metadata Areas    1
     Metadata Sequence No 5
     VG Access       read/write
     VG Status       resizable
     MAX LV        0
     Cur LV        4
     Open LV        4
     Max PV        0
     Cur PV        1
     Act PV        1
     VG Size        19.51 GiB
     PE Size        4.00 MiB
     Total PE       4994
     Alloc PE / Size    4994 / 19.51 GiB
     Free PE / Size    0 / 0
     VG UUID        Gcm5Ml-fc88-Xk5q-xuPC-Kj7Y-alfK-i770Gc
    [root@Candy ~]# lvscan
     ACTIVE      '/dev/vg_candy/usr' [4.00 GiB] inherit
     ACTIVE      '/dev/vg_candy/var' [4.00 GiB] inherit
     ACTIVE      '/dev/vg_candy/home' [4.00 GiB] inherit
     ACTIVE      '/dev/vg_candy/root' [7.51 GiB] inherit
    [root@Candy ~]#

    知道lvm卷组叫 'vg_candy'了, 我们就使用vgextend来向lvm 'vg_candy' 卷组添加成员了.

    [root@Candy ~]# vgextend vag_candy /dev/sdb1
    Physical volume "/dev/sdb1" successfully created
    Volume group "vg_candy" successfully extended

    现在我们再用vgs命令看一下pv个数:

    [root@Candy ~]# vgs
    VG    #PV #LV #SN Attr  VSize VFree
    vg_candy  2  4  0 wz--n- 4.02t 4.00t

    大家对比未添加时的vgs是否有看到PV个数从1变为2了!

    现在让我们用vgdisplay看看现在分区的容量.

    [root@Candy ~]# vgdisplay
     --- Volume group ---
     VG Name        vg_candy
     System ID
     Format        lvm2
     Metadata Areas    2
     Metadata Sequence No 6
     VG Access       read/write
     VG Status       resizable
     MAX LV        0
     Cur LV        4
     Open LV        4
     Max PV        0
     Cur PV        2
     Act PV        2
     VG Size        4.02 TiB
     PE Size        4.00 MiB
     Total PE       1053569
     Alloc PE / Size    4994 / 19.51 GiB
     Free PE / Size    1048575 / 4.00 TiB
     VG UUID        Gcm5Ml-fc88-Xk5q-xuPC-Kj7Y-alfK-i770Gc

    再次对比未添加的vgdiplay命令发现,FreePE 的value 从 0 / 0 变为 1048575 / 4.00 TiB . 这样说明Candy已经成功将4TB的lvm 分区添加进入到vg_candy 逻辑卷组里了。

    现在我们对所有逻辑分区进行扩容前,df -h 看看有哪些分区。

    [root@Candy ~]# df -h
    Filesystem         Size Used Avail Use% Mounted on
    /dev/mapper/vg_candy-root 7.3G 231M 6.7G  4% /
     tmpfs           1.9G   0 1.9G  0% /dev/shm
    /dev/sda1         477M  30M 422M  7% /boot
    /dev/mapper/vg_candy-home 3.9G 8.0M 3.7G  1% /home         
    /dev/mapper/vg_candy-usr  3.9G 382M 3.3G 11% /usr
    /dev/mapper/vg_candy-var  3.9G  63M 3.6G  2% /var

    现在麻烦的事已经做完了,接下来就剩下为分区进行扩容了.

    为磁盘进行扩容

    假设:我们需要向 这些分区都添加500G容量: //home/usr/var

    [root@Candy ~]# lvextend -L +500G /dev/mapper/vg_candy-root
     Size of logical volume vg_candy/root changed from 7.51 GiB (1922 extents) to 507.51 GiB (129922 extents).
     Logical volume root successfully resized
     
    [root@Candy ~]# lvextend -L +500G /dev/mapper/vg_candy-home
     Size of logical volume vg_candy/home changed from 4.00 GiB (1024 extents) to 504.00 GiB (129024 extents).
     Logical volume home successfully resized
     
    [root@Candy ~]# lvextend -L +500G /dev/mapper/vg_candy-usr
     Size of logical volume vg_candy/usr changed from 4.00 GiB (1024 extents) to 504.00 GiB (129024 extents).
     Logical volume usr successfully resized
     
    [root@Candy ~]# lvextend -L +500G /dev/mapper/vg_candy-var
     Size of logical volume vg_candy/var changed from 4.00 GiB (1024 extents) to 504.00 GiB (129024 extents).
     Logical volume var successfully resized

    大家注意,这一步操作时不可逆的! 如果输入了错误的分区名字还好! 如果添加到其它分区了,就得重复N遍来缩容,比较麻烦哦! 建议大家注仔细核对上面的FileSystem. 切记切记....

    提示扩容成功! 让我们再次用上述命令查看LVM信息:

    [root@Candy ~]# vgs
     VG    #PV #LV #SN Attr  VSize VFree
     vg_candy  2  4  0 wz--n- 4.02t 2.05t 
     
    [root@Candy ~]# lvscan
     ACTIVE      '/dev/vg_candy/usr' [504.00 GiB] inherit
     ACTIVE      '/dev/vg_candy/var' [504.00 GiB] inherit
     ACTIVE      '/dev/vg_candy/home' [504.00 GiB] inherit
     ACTIVE      '/dev/vg_candy/root' [507.51 GiB] inherit
     
    [root@Candy ~]# vgdisplay
     --- Volume group ---
     VG Name        vg_candy
     System ID
     Format        lvm2
     Metadata Areas    2
     Metadata Sequence No 10
     VG Access       read/write
     VG Status       resizable
     MAX LV        0
     Cur LV        4
     Open LV        4
     Max PV        0
     Cur PV        2
     Act PV        2
     VG Size        4.02 TiB
     PE Size        4.00 MiB
     Total PE       1053569
     Alloc PE / Size    516994 / 1.97 TiB
     Free PE / Size    536575 / 2.05 TiB
     VG UUID        Gcm5Ml-fc88-Xk5q-xuPC-Kj7Y-alfK-i770Gc
     
    [root@Candy ~]# df -h
    Filesystem         Size Used Avail Use% Mounted on
    /dev/mapper/vg_candy-root 7.3G 231M 6.7G  4% /
     tmpfs           1.9G   0 1.9G  0% /dev/shm
    /dev/sda1         477M  30M 422M  7% /boot
    /dev/mapper/vg_candy-home 3.9G 8.0M 3.7G  1% /home         
    /dev/mapper/vg_candy-usr  3.9G 382M 3.3G 11% /usr
    /dev/mapper/vg_candy-var  3.9G  63M 3.6G  2% /var

    看到这里大家可能奇怪! 为什么df -h 还没变呢?

    刷新磁盘信息与写入

    我们需要用resize2fs 重设分区大小, 这样才能使df -h 也能生效.

    而resize2fs 需要的时间与你给予的容量线性叠加. 也就是说你给的容量越多,resize2fs 的需要的时间就越多。

    [root@Candy ~]# resize2fs /dev//mapper/vg_candy-root
    resize2fs 1.41.12 (17-May-2010)
    Filesystem at /dev//mapper/vg_candy-root is mounted on /; on-line resizing required old desc_blocks = 1, new_desc_blocks = 32
    Performing an on-line resize of /dev//mapper/vg_candy-root to 133040128 (4k) blocks.
    The filesystem on /dev//mapper/vg_candy-root is now 133040128 blocks long.
    
    [root@Candy ~]# resize2fs /dev//mapper/vg_candy-usr
    resize2fs 1.41.12 (17-May-2010)
    Filesystem at /dev//mapper/vg_candy-usr is mounted on /usr; on-line resizing required old desc_blocks = 1, new_desc_blocks = 32
    Performing an on-line resize of /dev//mapper/vg_candy-usr to 132120576 (4k) blocks.
    The filesystem on /dev//mapper/vg_candy-usr is now 132120576 blocks long.
    
    [root@Candy ~]# resize2fs /dev//mapper/vg_candy-var
    resize2fs 1.41.12 (17-May-2010)
    Filesystem at /dev//mapper/vg_candy-var is mounted on /var; on-line resizing required old desc_blocks = 1, new_desc_blocks = 32
    Performing an on-line resize of /dev//mapper/vg_candy-var to 132120576 (4k) blocks.
    The filesystem on /dev//mapper/vg_candy-var is now 132120576 blocks long.
    
    [root@Candy ~]# resize2fs /dev//mapper/vg_candy-home
    resize2fs 1.41.12 (17-May-2010)
    Filesystem at /dev//mapper/vg_candy-home is mounted on /home; on-line resizing required old desc_blocks = 1, new_desc_blocks = 32
    Performing an on-line resize of /dev//mapper/vg_candy-home to 132120576 (4k) blocks.
    The filesystem on /dev//mapper/vg_candy-home is now 132120576 blocks long.
    
    [root@Candy ~]# df -h
    Filesystem          Size Used Avail Use% Mounted on
    /dev/mapper/vg_candy-root   500G 245M 474G  1% /
    tmpfs             1.9G   0 1.9G  0% /dev/shm
    /dev/sda1           477M  30M 422M  7% /boot
    /dev/mapper/vg_candy-home   496G  16M 471G  1% /home
    /dev/mapper/vg_candy-usr   496G 390M 471G  1% /usr
    /dev/mapper/vg_candy-var   496G  71M 471G  1% /var

    结束语

    顺便给大家晒一张重启后系统自动挂载的图!

    Linux系统还是比较聪明的. 其实重启与不重启都能使用, 只是为大家演示重启后的效果.

    以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。

    上一篇:在Windows Server 2016中启用Flash的方法
    下一篇:Linux 下安装pip包的方法
  • 相关文章
  • 

    © 2016-2020 巨人网络通讯

    时间:9:00-21:00 (节假日不休)

    地址:江苏信息产业基地11号楼四层

    《增值电信业务经营许可证》 苏B2-20120278

    详解基于Linux的LVM无缝磁盘水平扩容 详解,基于,Linux,的,LVM,无缝,