创建物理卷报错Can't open /dev/sdb5 exclusively. Mounted filesystem的问题解决过程记录

yum服务器lvm扩容，data目录是yum存放rpm包的目录，只有20G，需要添加磁盘扩容到80G



# df -lh

Filesystem                 Size  Used Avail Use% Mounted on

/dev/mapper/vg_node5-root   20G  479M   18G   3% /

tmpfs                      935M     0  935M   0% /dev/shm

/dev/sda1                  485M   39M  421M   9% /boot

/dev/mapper/vg_node5-data   20G  172M   19G   1% /data

/dev/mapper/vg_node5-usr   9.7G  1.6G  7.6G  18% /usr

/dev/mapper/vg_node5-web    15G  165M   14G   2% /web





1.添加一块硬盘





2.对硬盘分区，并将格式调整为8e即linux lvm格式

#挂载系统分区

# kpartx -l /dev/sdb

# kpartx -af /dev/sdb

# partx -a /dev/sdb





3.创建物理卷

在将几块盘做LVM时，遇到一个之前都没遇到过的问题:

# pvcreate /dev/sdb5

  Can't open /dev/sdb5 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:





# cat /proc/partitions

major minor  #blocks  name





   8        0   83886080 sda

   8        1     512000 sda1

   8        2   83373056 sda2

   8       16  125829120 sdb

   8       17          1 sdb1

   8       21  125796982 sdb5

 253        0   20480000 dm-0

 253        1    4096000 dm-1

 253        2   15360000 dm-2

 253        3   20480000 dm-3

 253        4   10240000 dm-4

 253        5          1 dm-5

 253        6  125796982 dm-6









# fdisk /dev/sdb -l





Disk /dev/sdb: 128.8 GB, 128849018880 bytes

255 heads, 63 sectors/track, 15665 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: 0x44c662ff





   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1               1       15665   125829081    5  Extended

/dev/sdb5               5       15665   125796982+  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@node5 /]# dmsetup status

sdb1: 0 2 linear 

vg_node5-web: 0 30720000 linear 

sdb5: 0 251593965 linear 

vg_node5-usr: 0 20480000 linear 

vg_node5-swap: 0 8192000 linear 

vg_node5-root: 0 40960000 linear 

vg_node5-data: 0 40960000 linear 

[root@node5 /]# dmsetup ls

sdb1 (253:5)

vg_node5-web (253:2)

sdb5 (253:6)

vg_node5-usr (253:4)

vg_node5-swap (253:1)

vg_node5-root (253:0)

vg_node5-data (253:3)





例如：

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)









# ll /dev/mapper/

total 0

crw-rw---- 1 root root 10, 58 Jul 26 19:51 control

lrwxrwxrwx 1 root root      7 Jul 26 19:59 vg_node5-data -> ../dm-3

lrwxrwxrwx 1 root root      7 Jul 26 19:59 /dev/sdb1 -> ../dm-5

lrwxrwxrwx 1 root root      7 Jul 26 19:59 /dev/sdb5 -> ../dm-6

lrwxrwxrwx 1 root root      7 Jul 26 19:59 vg_node5-root -> ../dm-0

lrwxrwxrwx 1 root root      7 Jul 26 19:59 vg_node5-swap -> ../dm-1

lrwxrwxrwx 1 root root      7 Jul 26 19:59 vg_node5-usr -> ../dm-4

lrwxrwxrwx 1 root root      7 Jul 26 19:59 vg_node5-web -> ../dm-2

使用 dmsetup remove xxx 移除掉就可以创建PV了:





# dmsetup remove /dev/sdb1

# dmsetup remove /dev/sdb5





重新创建物理卷成功

root@ubuntu:~# pvcreate /dev/sdb5

  Physical volume "/dev/sdb5" successfully created

也可以使用dmsetup remove_all移除所有。





# vgdisplay 

  --- Volume group ---

  VG Name               vg_node5

  System ID             

  Format                lvm2

  Metadata Areas        1

  Metadata Sequence No  6

  VG Access             read/write

  VG Status             resizable

  MAX LV                0

  Cur LV                5

  Open LV               5

  Max PV                0

  Cur PV                1

  Act PV                1

  VG Size               79.51 GiB

  PE Size               4.00 MiB

  Total PE              20354

  Alloc PE / Size       17250 / 67.38 GiB

  Free  PE / Size       3104 / 12.12 GiB

  VG UUID               tNuKXc-UdQO-Z8BK-ZtOQ-W93k-pqui-HAxKja





4.对物理卷vg_node5进行扩容

# vgextend vg_node5 /dev/sdb5

  Volume group "vg_node5" successfully extended

[root@node5 ~]# vgs

  VG       #PV #LV #SN Attr   VSize   VFree  

  vg_node5   2   5   0 wz--n- 199.47g 132.09g





将逻辑卷vg_node5-data即/data分区扩容到80G

[root@node5 ~]# lvextend -L 80G /dev/mapper/vg_node5-data 

  Extending logical volume data to 80.00 GiB

  Logical volume data successfully resized





重新读取大小

[root@node5 ~]# resize2fs /dev/mapper/vg_node5-data 

resize2fs 1.41.12 (17-May-2010)

Filesystem at /dev/mapper/vg_node5-data is mounted on /data; on-line resizing required

old desc_blocks = 2, new_desc_blocks = 5

Performing an on-line resize of /dev/mapper/vg_node5-data to 20971520 (4k) blocks.

The filesystem on /dev/mapper/vg_node5-data is now 20971520 blocks long.





[root@node5 ~]# df -lh

Filesystem                 Size  Used Avail Use% Mounted on

/dev/mapper/vg_node5-root   20G  479M   18G   3% /

tmpfs                      935M     0  935M   0% /dev/shm

/dev/sda1                  485M   39M  421M   9% /boot

/dev/mapper/vg_node5-data   79G  184M   75G   1% /data

/dev/mapper/vg_node5-usr   9.7G  1.6G  7.6G  18% /usr

/dev/mapper/vg_node5-web    15G  165M   14G   2% /web