可用空间不足：需要 X 个范围，但只有 Y 个可用

Question

我正在尝试在 Vmware Workstation 12 Pro CentOS VM 中扩展 LVM。以下是我正在遵循的步骤以及我停止的位置，因为不知道如何从那里开始：

1. 使用fdisk命令创建主分区

2. 使用fdisk -l以下方法获取分区表信息：

   # fdisk -l
   
   Disk /dev/sda: 85.9 GB, 85899345920 bytes
   255 heads, 63 sectors/track, 10443 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: 0x0001d929
   
      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        5222    41430016   8e  Linux LVM
   /dev/sda3            5222       10443    41940357+  8e  Linux LVM
   
   Disk /dev/mapper/vg_webserver-lv_root: 38.3 GB, 38277218304 bytes
   255 heads, 63 sectors/track, 4653 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_webserver-lv_swap: 4143 MB, 4143972352 bytes
   255 heads, 63 sectors/track, 503 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
   

3. 将分区转换为物理卷：

   # pvcreate /dev/sda3
     Physical volume "/dev/sda3" successfully created  
   

4. 获取要扩展的卷的名称：

   # vgdisplay
     --- Volume group ---
     VG Name               vg_webserver
     System ID
     Format                lvm2
     Metadata Areas        1
     Metadata Sequence No  3
     VG Access             read/write
     VG Status             resizable
     MAX LV                0
     Cur LV                2
     Open LV               2
     Max PV                0
     Cur PV                1
     Act PV                1
     VG Size               39.51 GiB
     PE Size               4.00 MiB
     Total PE              10114
     Alloc PE / Size       10114 / 39.51 GiB
     Free  PE / Size       0 / 0
     VG UUID               qo4qm0-yTZc-TVzt-Ys0t-Ap2j-sH4X-rtMqPS
   

5. 扩展物理卷：

   # vgextend vg_webserver /dev/sda3
     Volume group "vg_webserver" successfully extended
   

6. 获得可用的“免费”空间：

   # vgextend vg_webserver /dev/sda3
     Volume group "vg_webserver" successfully extended
   

7. 获取逻辑卷的信息：

   # lvdisplay
     --- Logical volume ---
     LV Path                /dev/vg_webserver/lv_root
     LV Name                lv_root
     VG Name                vg_webserver
     LV UUID                ayl9Ae-Y7nk-CVXG-c0G1-P4vx-wdlD-hEmXSO
     LV Write Access        read/write
     LV Creation host, time webserver.localhost, 2015-10-27 12:48:48 -0400
     LV Status              available
     # open                 1
     LV Size                35.65 GiB
     Current LE             9126
     Segments               1
     Allocation             inherit
     Read ahead sectors     auto
     - currently set to     256
     Block device           253:0
   
     --- Logical volume ---
     LV Path                /dev/vg_webserver/lv_swap
     LV Name                lv_swap
     VG Name                vg_webserver
     LV UUID                vwXfta-tGr0-kQFI-B2vF-L4gT-skE5-yb5qXA
     LV Write Access        read/write
     LV Creation host, time webserver.localhost, 2015-10-27 12:48:52 -0400
     LV Status              available
     # open                 1
     LV Size                3.86 GiB
     Current LE             988
     Segments               1
     Allocation             inherit
     Read ahead sectors     auto
     - currently set to     256
     Block device           253:1
   

8. 扩展逻辑卷：

   # lvextend -L+40G /dev/vg_webserver/lv_root
     Insufficient free space: 10240 extents needed, but only 10239 available
   

我收到了上面的错误，我不知道从那里去哪里以及如何解决这个问题，有什么可以帮助我的吗？我做错了什么，我正在运行的问题背后的逻辑解释是什么？

注意：我已阅读此内容，但我不确定如何撤消我已经进行的所有更改，以及此信息是否是要遵循的路径

更新

根据这里的要求是以下命令的输出：

# pvdisplay
  --- Physical volume ---
  PV Name               /dev/sda2
  VG Name               vg_webserver
  PV Size               39.51 GiB / not usable 3.00 MiB
  Allocatable           yes (but full)
  PE Size               4.00 MiB
  Total PE              10114
  Free PE               0
  Allocated PE          10114
  PV UUID               mwFIHY-mwwJ-b3uk-PkbP-7JXp-Vp2t-foCZtt

  --- Physical volume ---
  PV Name               /dev/sda3
  VG Name               vg_webserver
  PV Size               40.00 GiB / not usable 1.38 MiB
  Allocatable           yes (but full)
  PE Size               4.00 MiB
  Total PE              10239
  Free PE               0
  Allocated PE          10239
  PV UUID               tWg4Oj-ZknB-mefb-Ggy9-V8Cu-C7S2-OvO5aU

# vgdisplay
  --- Volume group ---
  VG Name               vg_webserver
  System ID
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  5
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                2
  Act PV                2
  VG Size               79.50 GiB
  PE Size               4.00 MiB
  Total PE              20353
  Alloc PE / Size       20353 / 79.50 GiB
  Free  PE / Size       0 / 0
  VG UUID               qo4qm0-yTZc-TVzt-Ys0t-Ap2j-sH4X-rtMqPS

# lvdisplay
  --- Logical volume ---
  LV Path                /dev/vg_webserver/lv_root
  LV Name                lv_root
  VG Name                vg_webserver
  LV UUID                ayl9Ae-Y7nk-CVXG-c0G1-P4vx-wdlD-hEmXSO
  LV Write Access        read/write
  LV Creation host, time webserver.localhost, 2015-10-27 12:48:48 -0400
  LV Status              available
  # open                 1
  LV Size                75.64 GiB
  Current LE             19365
  Segments               2
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:0

  --- Logical volume ---
  LV Path                /dev/vg_webserver/lv_swap
  LV Name                lv_swap
  VG Name                vg_webserver
  LV UUID                vwXfta-tGr0-kQFI-B2vF-L4gT-skE5-yb5qXA
  LV Write Access        read/write
  LV Creation host, time webserver.localhost, 2015-10-27 12:48:52 -0400
  LV Status              available
  # open                 1
  LV Size                3.86 GiB
  Current LE             988
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           253:1

Answer 1

我认为是工作中的一些四舍五入导致您lvextend失败。

尝试这个： lvextend /dev/vg_webserver/lv_root -l+100%FREE

上述命令将要求系统将所有可用空间分配给选定的逻辑卷，而不要求特定大小。