1.3.1 LVM条带化error

报错：​

#pvcreate /dev/dfb2 /dev/dfa2 /dev/dfc2 /dev/dfd2 already exists in filesystem

  Can't open /dev/dfa2 exclusively.  Mounted filesystem?

  Can't open /dev/dfb2 exclusively.  Mounted filesystem?

  Can't open /dev/dfc2 exclusively.  Mounted filesystem?

  Can't open /dev/dfd2 exclusively.  Mounted filesystem?

  Device already not found (or ignored by filtering).

  Device exists not found (or ignored by filtering).

  Device in not found (or ignored by filtering).

  Device filesystem not found (or ignored by filtering).

 

解决方案：

LVM 'Can’t open /dev/sdb1 exclusively. Mounted filesystem?' Problem

27 Jun 2014

在将几块盘做LVM时，遇到一个之前都没遇到过的问题:

root@ubuntu:~# pvcreate /dev/sdc1
  Can't open /dev/sdc1 exclusively.  Mounted filesystem?

首先第一反应就是查看这个分区是否已经在使用了，但是没有。

查看硬盘的一些信息:

root@ubuntu:~# cat /proc/partitions
major minor  #blocks  name

  80  488386584 sda
   8        116777216 sda1
   8        2471608344 sda2
   832  488386584 sdc
   833  488386584 sdc1
   816  488386584 sdb
   817  488385560 sdb1
   848  488386584 sdd
   849  488384001 sdd1
 254        0838860800 dm-0
 254        14194304 dm-1
 254        2488386584 dm-2
 254        3488386584 dm-3
 254        5488384001 dm-5
 254        4488384001 dm-4

root@ubuntu:~# fdisk /dev/sdc -l

Disk /dev/sdc: 500.1 GB, 500107862016 bytes
81 heads, 63 sectors/track, 191411 cylinders, total 976773168 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
Disk identifier: 0xbbbab9b8

Device Boot      Start         End      BlocksId  System
/dev/sdc1            2048   976773167488385560   8e  Linux LVM

接着看一些底层的信息:

dmsetup 是一个底层的逻辑卷管理， dm 应该是 Device Mapper的简称。

root@ubuntu:~# dmsetup status
35000c50026716847: 0 976773168 multipath 2 0 0 0 1 1 A 0 1 0 8:48 A 0
vg_data-lv_home: 0 976764928 linear
vg_data-lv_home: 976764928 700956672 linear
35000c5002670f03e: 0 976773168 multipath 2 0 0 0 1 1 A 0 1 0 8:32 A 0
35000c5002670f03e-part1: 0 976768002 linear
35000c50026716847-part1: 0 976768002 linear
vg_data-lv_swap: 0 8388608 linear

root@ubuntu:~# dmsetup ls
35000c50026716847       (254, 2)
vg_data-lv_home (254, 0)
35000c5002670f03e       (254, 3)
35000c5002670f03e-part1 (254, 5)
35000c50026716847-part1 (254, 4)
vg_data-lv_swap (254, 1)

可以看到 35000c5002670f03e 和 35000c50026716847 组成了multipath(多路径)

root@ubuntu:~# multipath -ll
35000c50026716847 dm-2 ATA,GB0500EAFJH
size=466G features='0' hwhandler='0' wp=rw
`-+- policy='round-robin 0' prio=1 status=active
  `- 3:0:0:0 sdd 8:48 active ready running
35000c5002670f03e dm-3 ATA,GB0500EAFJH
size=466G features='0' hwhandler='0' wp=rw
`-+- policy='round-robin 0' prio=1 status=active
  `- 2:0:0:0 sdc 8:32 active ready running

root@ubuntu:~# ll /dev/mapper/
total 0
drwxr-xr-x  2 root root     180 Jun 28 01:39 ./
drwxr-xr-x 14 root root   13060 Jun 28 17:17 ../
lrwxrwxrwx  1 root root       7 Jun 28 01:39 35000c5002670f03e -> ../dm-3
lrwxrwxrwx  1 root root       7 Jun 28 01:39 35000c5002670f03e-part1 -> ../dm-5
lrwxrwxrwx  1 root root       7 Jun 28 01:39 35000c50026716847 -> ../dm-2
lrwxrwxrwx  1 root root       7 Jun 28 01:39 35000c50026716847-part1 -> ../dm-4
crw------T  1 root root 10, 236 Jun 28 01:39 control
lrwxrwxrwx  1 root root       7 Jun 28 01:39 vg_data-lv_home -> ../dm-0
lrwxrwxrwx  1 root root       7 Jun 28 01:39 vg_data-lv_swap -> ../dm-1

使用 dmsetup remove xxx 移除掉就可以创建PV了:

root@ubuntu:~# dmsetup remove 35000c5002670f03e-part1
root@ubuntu:~# dmsetup remove 35000c5002670f03e

root@ubuntu:~# pvcreate /dev/sdc1
  Physical volume "/dev/sdc1" successfully created

也可以使用dmsetup remove_all移除所有。

TODO: 继续研究