2019 年 7 月 – 小顾de杂记

这里假设分区表都是正确的，我们拿上面的文章举例子：

# fdisk -l OMP120.img
Disk OMP120.img: 29.8 GiB, 31937527808 bytes, 62377984 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x000d89e6
 
Device      Boot   Start      End  Sectors  Size Id Type
OMP120.img1 *       2048  1026047  1024000  500M 83 Linux
OMP120.img2      1026048 59691007 58664960   28G 8e Linux LVM

# fdisk -l OMP120.img

Disk OMP120.img: 29.8 GiB, 31937527808 bytes, 62377984 sectors

Units: sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disklabel type: dos

Disk identifier: 0x000d89e6

Device Boot Start End Sectors Size Id Type

OMP120.img1 * 2048 1026047 1024000 500M 83 Linux

OMP120.img2 1026048 59691007 58664960 28G 8e Linux LVM

一个sectors是512k，分区表尾部规划的空间结尾是59691007，那么切除偏移是

truncate --size=$[(59691007+1)*512] OMP120.img

1	truncate --size=$[(59691007+1)*512] OMP120.img

[......]

继续阅读

拿到镜像是这样的。

$ fdisk -l OMP120.img
Disk OMP120.img: 29.8 GiB, 31937527808 bytes, 62377984 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x000d89e6

Device      Boot   Start      End  Sectors  Size Id Type
OMP120.img1 *       2048  1026047  1024000  500M 83 Linux
OMP120.img2      1026048 62377983 61351936 29.3G 8e Linux LVM

$ fdisk -l OMP120.img

Disk OMP120.img: 29.8 GiB, 31937527808 bytes, 62377984 sectors

Units: sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disklabel type: dos

Disk identifier: 0x000d89e6

Device Boot Start End Sectors Size Id Type

OMP120.img1 * 2048 1026047 1024000 500M 83 Linux

OMP120.img2 1026048 62377983 61351936 29.3G 8e Linux LVM

losetup伺候，其中，LVM内是如下情况

# pvs -v --segments
    Wiping internal VG cache
    Wiping cache of LVM-capable devices
  PV           VG        Fmt  Attr PSize  PFree Start SSize LV      Start Type   PE Ranges             
  /dev/loop0p2 vg_wellav lvm2 a--  29.25g    0      0  6728 lv_root     0 linear /dev/loop0p2:0-6727   
  /dev/loop0p2 vg_wellav lvm2 a--  29.25g    0   6728   761 lv_swap     0 linear /dev/loop0p2:6728-7488

# pvs -v --segments

Wiping internal VG cache

Wiping cache of LVM-capable devices

PV VG Fmt Attr PSize PFree Start SSize LV Start Type PE Ranges

/dev/loop0p2 vg_wellav lvm2 a-- 29.25g 0 0 6728 lv_root 0 linear /dev/loop0p2:0-6727

/dev/loop0p2 vg_wellav lvm2 a-- 29.25g 0 6728 761 lv_swap 0 linear /dev/loop0p2:6728-7488

但是这个pv卷轴已经没有空余空间，因为是离线镜像所以不能使得分区属性有任何变化，包括uuid[......]

继续阅读

一	二	三	四	五	六	日
1	2	3	4	5	6	7
8	9	10	11	12	13	14
15	16	17	18	19	20	21
22	23	24	25	26	27	28
29	30	31

月度归档： 2019 年 7 月

安全切除一个磁盘镜像img的尾部的空余空间

记录一次磁盘镜像的LVM分区缩小调整过程