Not all fixed. Re: Has anybody had good luck using FAI where it repartitions on a system that previously contained an lvm setup?

[Ken Hahn]

Hello,

I'm worried I'm echoing in my own thread here, but here is what I've found:

setup-storage depends on liblinux-lvm-perl

While that library has been redone, both versions of it just seems to
pass through the same problem.  The ultimate problem is that logical
volume information is derived from executing the "vgdisplay -v" command.

The output from this command has changed between squeeze and wheezy.
The older version of this command has fewer fields.

snippet of older output:
  LV Name                /dev/vg/var
  VG Name                vg

snippit of newer output:
  LV Path                /dev/vg/var
  LV Name                var
  VG Name                vg


They've added a field, and changed what is contained in the old named field.

I'm not sure if this is a change in the lvm tools or a change in the
kernel interface, but it sure as heck messes with setup-storage.

I'll go send a bug to the liblinux-lvm-perl debian package, but
ultimately, I bet they just pass along another field as a fix.

Anyway, apparently, this bug has legs.

-Ken


On 07/19/2013 05:14 PM, Ken Hahn wrote:
> Hey,
> 
> Still looking at this issue (been gone to a conference), but I'm noting
> that FAI/debian changed from using liblinux-lvm-perl .14-2 to .16-1.
> This ends up changing what the "current device tree" looks like.
> Specifically it appears the lv's are represented by /dev/ paths in the
> old version and by volume name only in the new version.  This is really
> significant because the post and pre depend on everything being a dev name.
> 
> Old method:
>           'VG_vg' => [
>                        '/dev/vg/fscache',
>                        '/dev/vg/local.hd',
>                        '/dev/vg/root',
>                        '/dev/vg/swap',
>                        '/dev/vg/var'
>                      ]
> 
> New method:
> 
>           'VG_vg' => [
>                        'fscache',
>                        'local.hd',
>                        'root',
>                        'swap',
>                        'var'
>                      ]
> 
> (I discovered this while trying to use the old setup-storage in a new fai.)
> 
> Also, note this info in the  Linux::LVM changelog:
> 
> 0.14  Wed Jul  2 02:54:14 CDT 2008
>         - Fixed some logic errors to get it working a little better
>         - Full rewrite underway
> 
> I guess one of my questions is: is this a bug in setup-storage, or a bug
> in Linux::LVM or perhaps even one of the lvm command line tools?
> 
> Also, how long have people be trying to give patches for setup-storage
> because of a difference that really arose in Linux::LVM?
> 
> If anybody has any info on this before I keep digging on Monday, it
> would be appreciated!
> 
> -Ken Hahn
>