Re: [linux-lvm] automatic repartitioning of devices in /etc/lvm/cache/.cache?

[travis+ml-linux-lvm@subspacefield.org]

On Fri, Aug 26, 2016 at 11:46:30AM +0100, Bryn M. Reeves wrote:
> Use audit, systemap, or even blktrace to constantly monitor the devices and
> report when something is writing to the MBR area.

Thanks!

> There have been several common proprietary applications that have been found
> to at times cause this type of problem (proprietary RDBMS, volume and cluster
> managers in particular).
> 
> Otherwise you can search through the mailing list archives - there have
> been a few threads discussing similar problems.
> 
> > Is there any way that being listed there could be a side effect, or be
> > a cause, of disk partition corruption in those devices?
> 
> Only if some external (non-lvm2) component were reading that file and
> acting on the contents. Nothing in lvm2 itself even knows how to write
> a GPT partition table.

Good to know.  Is it possible that whatever restored a GPT (bizarrely,
to the partition not the disk) also restored an LVM header and that
the device ended up in the LVM cache via some automatic periodic
process, or a boot-time process?

Second question: What is that cache for, exactly?
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