Thanks Roger, Zdenek,

I have my ZVOL on my NAS exposed as LUNs. The initiator were switched off
and for unknown reason I found my NAS switched off as well.
It had run for long and I feared the worst (CPU/motherboard/etc). Instead
once powered up everything started to work again but the LUNs that seemed
to jeopardized.
I have many ZVOLs used by ESXi in which I have EVE-NG who uses LVM and such
ZVOLs have the same size so I wanted to inspect them to check the hostname.

Now some LUNs started to work normally, some others still behave weirdly. I
will run pvs on them with extra debugs to see what's going on.

Many thanks,

Alex

Le jeu. 23 sept. 2021 à 23:48, Roger Heflin <rogerheflin@gmail.com> a
écrit :

> If you have lvmetad running and in use then the lvm commands ask it
> what the system has on it.
>
> I have seen on random boots fairly separated systems (rhel7 versions,
> and many years newer fedora systems) at random fail to find one or
> more pv.s
>
> I have disabled it at home, and in my day job we have also disabled
> (across 20k+ systems) as we confirmed it had inconsistency issues
> several times on a variety of our newest installs.
>
> Stopping lvmetad and/or restarting it would generally fix it.    But
> it was a source of enough random issues(often failure to mount on a
> boot, so often issues that resulted in page-outs to debug)  and did
> not speed things up much enough to be worth it even on devices with
> >2000 SAN volumes.
>
> On Thu, Sep 23, 2021 at 8:52 AM Zdenek Kabelac <zkabelac@redhat.com>
> wrote:
> >
> > Dne 22. 09. 21 v 18:48 alessandro macuz napsal(a):
> > > fdisk correctly identifies the extended partition as 8e.
> > > I wonder which kind of data lvmdiskscan and pvs use in order to list
> LVM
> > > physical volumes.
> > > Does PVS check some specific metadata within the partition without just
> > > relying on the type of partition displayed by fdisk?
> > >
> > >
> >
> > Hi
> >
> > Yes - PVs do have header signature keeping information about PV
> attributes
> > and also has the storage area to keep lvm2 metadata.
> >
> > Partition flags known to fdisk are irrelevant.
> >
> >
> > Regards
> >
> > Zdenek
> >
> > _______________________________________________
> > linux-lvm mailing list
> > linux-lvm@redhat.com
> > https://listman.redhat.com/mailman/listinfo/linux-lvm
> > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
> >
>