Re: [gentoo-user] Re: LVM2 problem, meta data format change?

2019-05-28 Thread Paul Colquhoun
On Tuesday, May 28, 2019 5:14:42 P.M. AEST Michael Haubenwallner wrote:
> Hi Paul,
> 
> as an LVM user without deeper knowledge, stumbled upon your question without
> any reply yet, and my fear was to run into the same when updating lvm2.
> On 5/17/19 2:26 PM, Paul Colquhoun wrote:
> > Recently I found that new kernels were not booting for me, because they
> > could not assemble the LVM partition that I use for the root filesystem.
> > 
> > Booting back to my old kernel still worked.
> > 
> > I have tracked this back to the lvm2 version.
> > 
> > After booting with the old kernel, I ran lvm and tried the 'fullreport'
> > command.
> > 
> > sys-fs/lvm2-2.02.184-r3 gives an error:
> > 
> > lvm> fullreport
> > 
> >  LV root invalid: visible raid meta LV for raid1 segment
> >  LV root invalid: visible raid meta LV for raid1 segment
> >  Internal error: LV segments corrupted in root.
> 
> Searching the web with parts of this error messages leads me to this commit:
> https://github.com/lvmteam/lvm2/commit/dd5716ddf258c4a44819fa90d3356833ccf7
> 67b4
> 
> While I have no idea about "visible SubLVs", maybe that commit message can
> tell something to you?
> 
> > After backing out to an earlier version, sys-fs/lvm2-2.02.183
> > the 'fullreport' actually gives a report.
> > 
> > I'm assuming the only reason the old kernel boots is that it has the older
> > lvm in the initramfs, and once assembled the handover to the live system
> > still works.
> > 
> > I can't find anything online that looks like the same thing to me, so I
> > was
> > wondering if anyone here had encountered a similar problem?
> > 
> > The next step is to try and find how to update the on-disk lvm meta data
> > so the later versions understand it, hopefully without having to rebuild
> > my system from scratch.
> 
> As far as I understand, this doesn't seem like a metadata format _change_,
> but a rare metadata consistency problem that goes unnoticed by the older
> version.


Once I deleted & re-created the logical volume the newer versions had no 
problem.

Unfortunately, since it was my root partition, that took moving data to a 
temporary volume, rebooting from there, re-creating the old LV, moving the 
data back, and rebooting again. Not a quick fix, even if it wasn't that 
difficult.


-- 
Reverend Paul Colquhoun, ULC. http://andor.dropbear.id.au/
  Asking for technical help in newsgroups?  Read this first:
 http://catb.org/~esr/faqs/smart-questions.html#intro






[gentoo-user] Re: LVM2 problem, meta data format change?

2019-05-28 Thread Michael Haubenwallner
Hi Paul,

as an LVM user without deeper knowledge, stumbled upon your question without
any reply yet, and my fear was to run into the same when updating lvm2.

On 5/17/19 2:26 PM, Paul Colquhoun wrote:
> Recently I found that new kernels were not booting for me, because they could 
> not assemble the LVM partition that I use for the root filesystem.
> 
> Booting back to my old kernel still worked.
> 
> I have tracked this back to the lvm2 version.
> 
> After booting with the old kernel, I ran lvm and tried the 'fullreport' 
> command.
> 
> sys-fs/lvm2-2.02.184-r3 gives an error:
> 
> lvm> fullreport 
>  LV root invalid: visible raid meta LV for raid1 segment 
>  LV root invalid: visible raid meta LV for raid1 segment 
>  Internal error: LV segments corrupted in root.

Searching the web with parts of this error messages leads me to this commit:
https://github.com/lvmteam/lvm2/commit/dd5716ddf258c4a44819fa90d3356833ccf767b4

While I have no idea about "visible SubLVs", maybe that commit message can
tell something to you?

> 
> After backing out to an earlier version, sys-fs/lvm2-2.02.183
> the 'fullreport' actually gives a report.
> 
> I'm assuming the only reason the old kernel boots is that it has the older 
> lvm 
> in the initramfs, and once assembled the handover to the live system still 
> works.
> 
> I can't find anything online that looks like the same thing to me, so I was 
> wondering if anyone here had encountered a similar problem?
> 
> The next step is to try and find how to update the on-disk lvm meta data so 
> the 
> later versions understand it, hopefully without having to rebuild my system 
> from scratch.

As far as I understand, this doesn't seem like a metadata format _change_, but
a rare metadata consistency problem that goes unnoticed by the older version.

HTH,
/haubi/