Re: [linux-lvm] Cannot access logical volume (open count=1)

["Bryn M. Reeves" <bmr@redhat.com>]

On 02/10/2011 09:14 PM, Peter Flass wrote:
> I'm truly sorry to bother the developers' list with this question, but 
> I've searched and can't find an ansewr that works.  A system crash seems 
> to have corrupted something in my fedora system.  I boot to a rescue CD 
> and look thru LVM.  The disk (sdb) has one vg and three lv's on it.  
> Call the vg vg_xxx, the lv's are lv_boot (ext3, I believe), lv_swap (no 
> fs) and lv_home (ext4).  I can't fsck (e2fsck) lv_home or do anything 
> else with it, LVM says it's open count=1 where the open count of the 
> other two lv's is zero.
> 
> I can't find who has it open.  /proc/mounts shows /dev/sdb1 mounted on 
> /media/usb0, when I umount  it (either by mount point or device) it 
> disappears, but the lv still shows open, and as a result I am unable to 
> do anything with it.  lsof also shows nothing open that resembles this 
> lv.  I can inactivate the other two lvs in this vg, but not lv_home.
> 
> What can I do to fix this problem?

What does "dmsetup ls --tree" look like?

E.g.:

$ sudo dmsetup ls --tree
tvg0-l0 (253:7)
 └─ (7:1)
bmr_vg1-swap (253:4)
 └─ (9:1)
luks-ca3de7ff-5487-4e9b-ac2b-846efc71b2e2 (253:5)
 └─bmr_vg0-data (253:2)
    └─ (9:2)
bmr_vg0-var (253:1)
 └─ (9:2)
luks-a48853af-19d8-4965-a346-d82ae4672b66 (253:6)
 └─bmr_vg0-home (253:3)
    └─ (9:2)
bmr_vg0-root (253:0)
 └─ (9:2)

Regards,
Bryn.