[linux-lvm] need help to recover my system

[Heinz J. Mauelshagen]

On Mon, Oct 02, 2000 at 02:33:18AM -0400, Les Hazelton wrote:
> Andreas,
> 
> Thanks.  That got me one step closer.  For some reason the patch I
> clipped from your note would not apply even though it appeared to match
> the existing source correctly. I applied it manually and re-compiled. At
> this point, running vgchange will activate the volume group. When I list
> the content of /proc/lvm it shows the 7 logical volumes i had defined.
> 
> All of the various display commands appear to work, but I can't mount
> any of the logical volumes. The mount command says the special device
> /dev/vg01/xxxx does not exist.

Even though it seems you have devfs in place, the device nodes for the
logical volumes are not created.

Does a vgscan run help you to create them?

> I checked the LVM-HOWTO and the only
> thing I see there is the requirement to make a filesystem on the new
> logical volume. Is the mkreiserfs/mke2fs the place the special device is
> created? 

No, it is created by a library routine either called by lvcreate, vgscan
or vgmknodes.

> If I do that it will destroy the existing data.

Yes, you would. Don't do that.
You just want to have your device nodes back and access the existing data.

Try vgmknodes after "vgchange -ay" on the volume group.

We need to figure out though, why the nodes are not created in the first
place by devfs.

Heinz

> It appears so
> close to being recovered yet still so far away.
> 
> ----------------------------
> [root at farpt1 /root]# lvdisplay /dev/vg01/usr
> --- Logical volume ---
> LV Name               /dev/vg01/usr
> VG Name               vg01
> LV Write Access       read/write
> LV Status             available
> LV #                  4
> # open                0
> LV Size               2.5 GB
> Current LE            640
> Allocated LE          640
> Allocation            next free
> Read ahead sectors    120
> Block device          58:3
> 
> ----------------------------------------
> [root at farpt1 /root]# mount -t reiserfs /dev/vg01/usr /vg01/usr
> mount: special device /dev/vg01/usr does not exist
> 
> -----------------------------------------
> [root at farpt1 /root]# ls -al /dev/vg01
> total 104
> dr-xr-xr-x    2 root     root         4096 Oct  2 01:45 ./
> drwxr-xr-x   12 root     root        98304 Oct  2 02:09 ../
> crw-r-----    1 root     root     109,   0 Oct  2 01:45 group
> 
> 
> Les Hazelton
> 
> Andreas Dilger wrote:
> > 
> > You write:
> > > When I booted the new 2.2.17 kernel I ran "pvscan -D" & "vgscan -D".  I
> > > can now do vgdisplay and lvmdisplay if I use the -D parameter.  I just
> > > can't activate the volume group.  When I try, this is the result.
> > >
> > > [root at farpt1 /root]# vgchange -va y
> > > vgchange -- locking logical volume manager
> > > vgchange -- finding all volume group(s)
> > > vgchange -- checking volume group name "vg01"
> > > vgchange -- checking existence of volume group "vg01"
> > > vgchange -- reading volume group data for "vg01" from lvmtab
> > > vgchange -- checking volume group consistency  of "vg01"
> > > vgchange -- checking if all physical volumes of volume group "vg01" are
> > > available
> > > vgchange -- creating VGDA for "vg01" in kernel
> > > vgchange -- can't open logical volume manager to activate volume group
> > > "vg01"
> > 
> > This looks like the same bug that YOSHIDA Daisuke just fixed (see message
> > "Re: vgchange.c patch for devfs"):
> > 
> > Cheers, Andreas
> > -------------------------------------------------------------------------
> > --- LVM/0.8final/tools/vgchange.c       Tue Feb 22 11:09:33 2000
> > +++ LVM.modified/0.8final/tools/vgchange.c      Sun Oct  1 12:50:40 2000
> > @@ -391,7 +391,13 @@
> >               if ( opt_v > 0) printf ( "%s -- creating VGDA for \"%s\" "
> >                                        "in kernel\n",
> >                                        cmd, vg_name);
> > -             if ( ( ret = vg_create ( vg_name, vg)) == 0)
> > +
> > +             ret = vg_create( vg_name, vg);
> > +             if ( ret == -LVM_EVG_CREATE_REMOVE_OPEN) {
> > +                vg_create_dir_and_group( vg);
> > +                ret = vg_create ( vg_name, vg);
> > +             }
> > +             if ( ret == 0)
> >                  printf ( "%s -- volume group \"%s\" successfully activated\n",
> >                           cmd, vg_name);
> >               else {
> > 
> > --
> > Andreas Dilger  \ "If a man ate a pound of pasta and a pound of antipasto,
> >                  \  would they cancel out, leaving him still hungry?"
> > http://www-mddsp.enel.ucalgary.ca/People/adilger/               -- Dogbert
> 
> -- 
> Les Hazelton
> ---------------------------------------------
> Good journey, longevity and prosperity to all

-- 

Regards,
Heinz      -- The LVM guy --

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Heinz Mauelshagen                                 Sistina Software Inc.
Senior Consultant/Developer                       Bartningstr. 12
                                                  64289 Darmstadt
                                                  Germany
Mauelshagen at Sistina.com                           +49 6151 7103 86
                                                       FAX 7103 96
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