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References: <kcim.5838018e.2209.36b950052698aabe@ucs.cubewerk.intern>
From: Zdenek Kabelac <zdenek.kabelac@gmail.com>
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Date: Fri, 25 Nov 2016 10:30:39 +0100
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Subject: Re: [linux-lvm] auto_activation_volume_list in lvm.conf not honored
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To: LVM general discussion and development <linux-lvm@redhat.com>

Dne 25.11.2016 v 10:17 Stefan Bauer napsal(a):
> Hi Peter,
>
> as i said, we have master/slave setup _without_ concurrent write/read. So i do not see a reason why i should take care of locking as only one node is activating the volume group at the same time.
>
> That should be fine - right?

Nope it's not.

Every i.e. activation  DOES validation of all resources and takes ACTION when 
something is wrong.

Sorry, but there is NO way to do this properly without locking manager.

Although many lvm2 users always do try to be 'innovative' and try to use in 
lock-less way - this seems to work most of the time - till the moment some
disaster happens - then just lvm2 is blamed about data loss..

Interestingly they never tried to think why we invested so much time into 
locking manager when there is such 'easy-fix' in their eyes...

IMHO lvmlockd is relatively 'low-resource/overhead' solution worth to be 
explored if you don't like clvmd...

Regards

Zdenek