Re: can't unmount

[C Anthony Risinger <anthony@extof.me>]

On Aug 12, 2010, at 12:57 PM, "K. Richard Pixley" <rich@noir.com> wrote:

> On 8/12/10 10:46 , C Anthony Risinger wrote:
>> On Aug 12, 2010, at 10:58 AM, "K. Richard Pixley"<rich@noir.com>
>> wrote:
>>> And should I be worried about what umount -l might be leaving
>>> behind?  (eg, any unfreed kernel resources)  Or is that a reasonable
>>> way to deal with this situation on an ongoing basis?
>>>
>>> On 8/12/10 08:55 , K. Richard Pixley wrote:
>>>> I'm running into a situation where I can't unmount a mounted
>>>> snapshot.  It shows "busy" even though neither lsof nor fuser show
>>>> any open files.  Umount -f doesn't work although umount -l does.
>>>>
>>>> Is there anything else I can do to debug this scenario or to clear
>>>> the busy status myself?  Or am I down to rebooting each time?
>>>>
>>>> This is on stock ubuntu-10.04, x86.
>> You are lazy unmounting, as I understand, you are essentially just
>> hiding the fact that the mount was busy to userspace... The mount
>> will
>> remain active in the kernel until you resolve whatever was stopping
>> umount in the first place; kernel will then silently unmount.
> Understood.
>> Does this affect all of your mounted snapshots, or only a particular
>> one?
> I'm only mounting one at a time so I haven't noticed.  Will check
> next time it occurs.

More than likely it's just an open app stopping the mount; make sure
any GUI stuff isn't looking at the drive, and no terminals are
either.  I thought that stuff shows up in lsof, but I swear there are
cases when things won't.

C Anthony [mobile]