[linux-lvm] dmsetup says "Device does not exist", though it exists
christoph.pleger at cs.uni-dortmund.de
Wed Aug 14 07:22:32 UTC 2019
>> I have a volume group with 20 logical volumes. Only the last one of
>> these volumes has a strange problem with dmsetup, shown by these
>> commands and output on the command line:
>> root at host:/home/linux# /sbin/dmsetup info -c -o name --noheadings
>> Device does not exist.
>> Command failed
>> root at host:/home/linux# lvdisplay -c /dev/vg/lv20
>> root at host:/home/linux# mount /dev/vg/lv20 /mnt
>> root at host:/home/linux# ls /mnt
>> lost+found data1 data2
>> That is, dmsetup says "Device does not exist" about a logical volume,
>> though the volume exists and is operating normally. What is the
>> possible problem here?
> Have you tried strace ?
I attached the relevant lines of the strace output. I am really
wondering what is happening there:
1. A stat() on /dev/mapper/lv20 is performed, though I requested
2. A stat() on/dev/mapper/vg-lv15-real is performed. What does this have
to do with lv20 (after I wrote what is at number 3, I know)
3. I do not even know where /dev/mapper/vg-lv15-real is coming from. I
created a logical volume named lv15, but none named lv15-real. And
really, 'ls -l /dev/vg/' does not list lv15-real, but 'ls -l
/dev/mapper' lists vg-lv15-real and shows that is has the same link
target /dev/dm-18 as lv20.
4. Though stat() found /dev/mapper/vg-lv15-real, ioctl() says that this
device does not exist.
> Kernel version, lvm version, distribution... ?
Kernel Debian amd64 4.9.168-1+deb9u2, LVM version 2.03.02(2), Debian 9
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
More information about the linux-lvm