[linux-lvm] need help to recover my system

[linux-lvm] need help to recover my system

[Les Hazelton]

I had a Mandrake 7.1 system running the 2.2.17 kernel with LVM and
reiserfs patches applied.  I have a 15Gb partition on /dev/hdc5 which
was one large PV. It supports one VG which has the logical volumes for
/usr, /home, /var, etc... Everything except /boot and / which were on
the hda drive as plain ext2 file systems.

I decided to move the root partition "/" to a logical volume on hdc5 and
all was going well until I deleted it from the ext2 system on hda6. So
now I have a perfectly good Linux system contained on the hdc5 PV which
I can't access.

I have test system (Mandrake 7.2-b) on the hda drive.  It has the
2.4.0-0.22 kernel distributed my Mandrake and I have been attempting to
recover using that system.  The problem is I keep getting these errors:

------------------------------------------------------------------------------
pvscan -- reading all physical volumes (this may take a while...)
pvscan -- ERROR "pv_read_all_pv(): lvm_dir_cache" reading physical
volumes
 
[root@farpt1 /root]# vgscan -v
vgscan -- removing "/etc/lvmtab" and "/etc/lvmtab.d"
vgscan -- reading all physical volumes (this may take a while...)
vgscan -- no volume groups found
-------------------------------------------------------------------------------

I was going to try a pvcreate for /dev/hdc5  but thought it would wipe
the partition clean and I don't want to start over if there is *any*
hope of recovering it.

Please, if anyone knows a way to recover this volume,  I would be
extremely grateful for the help.

Les Hazelton

Re: [linux-lvm] need help to recover my system

[Heinz J. Mauelshagen]

On Sat, Sep 30, 2000 at 11:02:36PM -0400, Les Hazelton wrote:
> I had a Mandrake 7.1 system running the 2.2.17 kernel with LVM and
> reiserfs patches applied.  I have a 15Gb partition on /dev/hdc5 which
> was one large PV. It supports one VG which has the logical volumes for
> /usr, /home, /var, etc... Everything except /boot and / which were on
> the hda drive as plain ext2 file systems.
> 
> I decided to move the root partition "/" to a logical volume on hdc5 and
> all was going well until I deleted it from the ext2 system on hda6.

How did you do that?
Did you create an inital ram disk to load the lvm driver and activate
the volume group?
Otherwise you can't access your volume group(s) anyway from the /boot
booted kernel.

> So
> now I have a perfectly good Linux system contained on the hdc5 PV which
> I can't access.
> 
> I have test system (Mandrake 7.2-b) on the hda drive.  It has the
> 2.4.0-0.22 kernel distributed my Mandrake and I have been attempting to
> recover using that system.  The problem is I keep getting these errors:
> 
> ------------------------------------------------------------------------------
> pvscan -- reading all physical volumes (this may take a while...)
> pvscan -- ERROR "pv_read_all_pv(): lvm_dir_cache" reading physical
> volumes

This error means, that no (compatible) entries could be found either
in /proc/partitions or, if /proc/partitions doesn't exist, in /dev.

Please check that these sources are valid on your Mandrake 7.2-b test system
and retry.

>  
> [root@farpt1 /root]# vgscan -v
> vgscan -- removing "/etc/lvmtab" and "/etc/lvmtab.d"
> vgscan -- reading all physical volumes (this may take a while...)
> vgscan -- no volume groups found
> -------------------------------------------------------------------------------
> 
> I was going to try a pvcreate for /dev/hdc5  but thought it would wipe
> the partition clean and I don't want to start over if there is *any*
> hope of recovering it.
> 
> Please, if anyone knows a way to recover this volume,  I would be
> extremely grateful for the help.
> 
> Les Hazelton

-- 

Regards,
Heinz      -- The LVM guy --

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

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

Re: [linux-lvm] need help to recover my system

[Les Hazelton]

My kernel had LVM support compiled in, not as a module.  I had created an initrd but
may have not done that correctly.  I think the real problem was that the grub loader
was installed on the root "/" partition and not the "/boot" partition.  I had booted
the new configuration several times without problem until I deleted the original "/"
partition.  That's when I realized where the grub loader was installed.

When I use linux fdisk I see the entry for hdc5 as Linux LVM (85) and if I do "cat
/proc/partitions"  there is an entry for /dev/hdc5.

If, while running my test system with kernel 2.4.0, I run the pvcreate command for
/dev/hdc5 will that destroy the existing PV, VG, LVM content that is currently their?

"Heinz J. Mauelshagen" wrote:

> On Sat, Sep 30, 2000 at 11:02:36PM -0400, Les Hazelton wrote:
> > I had a Mandrake 7.1 system running the 2.2.17 kernel with LVM and
> > reiserfs patches applied.  I have a 15Gb partition on /dev/hdc5 which
> > was one large PV. It supports one VG which has the logical volumes for
> > /usr, /home, /var, etc... Everything except /boot and / which were on
> > the hda drive as plain ext2 file systems.
> >
> > I decided to move the root partition "/" to a logical volume on hdc5 and
> > all was going well until I deleted it from the ext2 system on hda6.
>
> How did you do that?
> Did you create an inital ram disk to load the lvm driver and activate
> the volume group?
> Otherwise you can't access your volume group(s) anyway from the /boot
> booted kernel.
>
> > So
> > now I have a perfectly good Linux system contained on the hdc5 PV which
> > I can't access.
> >
> > I have test system (Mandrake 7.2-b) on the hda drive.  It has the
> > 2.4.0-0.22 kernel distributed my Mandrake and I have been attempting to
> > recover using that system.  The problem is I keep getting these errors:
> >
> > ------------------------------------------------------------------------------
> > pvscan -- reading all physical volumes (this may take a while...)
> > pvscan -- ERROR "pv_read_all_pv(): lvm_dir_cache" reading physical
> > volumes
>
> This error means, that no (compatible) entries could be found either
> in /proc/partitions or, if /proc/partitions doesn't exist, in /dev.
>
> Please check that these sources are valid on your Mandrake 7.2-b test system
> and retry.
>
> >
> > [root@farpt1 /root]# vgscan -v
> > vgscan -- removing "/etc/lvmtab" and "/etc/lvmtab.d"
> > vgscan -- reading all physical volumes (this may take a while...)
> > vgscan -- no volume groups found
> > -------------------------------------------------------------------------------
> >
> > I was going to try a pvcreate for /dev/hdc5  but thought it would wipe
> > the partition clean and I don't want to start over if there is *any*
> > hope of recovering it.
> >
> > Please, if anyone knows a way to recover this volume,  I would be
> > extremely grateful for the help.
> >
> > Les Hazelton
>
> --
>
> Regards,
> Heinz      -- The LVM guy --
>
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
>
> Heinz Mauelshagen                                 Sistina Software Inc.
> Senior Consultant/Developer                       Bartningstr. 12
>                                                   64289 Darmstadt
>                                                   Germany
> Mauelshagen@Sistina.com                           +49 6151 7103 86
>                                                        FAX 7103 96
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

Les Hazelton

Re: [linux-lvm] need help to recover my system

[Heinz J. Mauelshagen]

On Sun, Oct 01, 2000 at 11:42:59AM -0400, Les Hazelton wrote:
> My kernel had LVM support compiled in, not as a module.  I had created an initrd but
> may have not done that correctly.  I think the real problem was that the grub loader
> was installed on the root "/" partition and not the "/boot" partition.  I had booted
> the new configuration several times without problem until I deleted the original "/"
> partition.  That's when I realized where the grub loader was installed.
> 
> When I use linux fdisk I see the entry for hdc5 as Linux LVM (85) and if I do "cat
> /proc/partitions"  there is an entry for /dev/hdc5.
> 
> If, while running my test system with kernel 2.4.0, I run the pvcreate command for
> /dev/hdc5 will that destroy the existing PV, VG, LVM content that is currently their?

Yes. You don't want to do that!

But it only allows you to do that using the "-ff" option of the
pvcreate command. Without that it complains _because_ the physical volume
still belongs to a volume group.

Could you supply the "pvscan -d" and the "vgscan -d" output from your test
system to enable further investigation on why LVM doesn't find your volume
group any longer?

Heinz

> 
> "Heinz J. Mauelshagen" wrote:
> 
> > On Sat, Sep 30, 2000 at 11:02:36PM -0400, Les Hazelton wrote:
> > > I had a Mandrake 7.1 system running the 2.2.17 kernel with LVM and
> > > reiserfs patches applied.  I have a 15Gb partition on /dev/hdc5 which
> > > was one large PV. It supports one VG which has the logical volumes for
> > > /usr, /home, /var, etc... Everything except /boot and / which were on
> > > the hda drive as plain ext2 file systems.
> > >
> > > I decided to move the root partition "/" to a logical volume on hdc5 and
> > > all was going well until I deleted it from the ext2 system on hda6.
> >
> > How did you do that?
> > Did you create an inital ram disk to load the lvm driver and activate
> > the volume group?
> > Otherwise you can't access your volume group(s) anyway from the /boot
> > booted kernel.
> >
> > > So
> > > now I have a perfectly good Linux system contained on the hdc5 PV which
> > > I can't access.
> > >
> > > I have test system (Mandrake 7.2-b) on the hda drive.  It has the
> > > 2.4.0-0.22 kernel distributed my Mandrake and I have been attempting to
> > > recover using that system.  The problem is I keep getting these errors:
> > >
> > > ------------------------------------------------------------------------------
> > > pvscan -- reading all physical volumes (this may take a while...)
> > > pvscan -- ERROR "pv_read_all_pv(): lvm_dir_cache" reading physical
> > > volumes
> >
> > This error means, that no (compatible) entries could be found either
> > in /proc/partitions or, if /proc/partitions doesn't exist, in /dev.
> >
> > Please check that these sources are valid on your Mandrake 7.2-b test system
> > and retry.
> >
> > >
> > > [root@farpt1 /root]# vgscan -v
> > > vgscan -- removing "/etc/lvmtab" and "/etc/lvmtab.d"
> > > vgscan -- reading all physical volumes (this may take a while...)
> > > vgscan -- no volume groups found
> > > -------------------------------------------------------------------------------
> > >
> > > I was going to try a pvcreate for /dev/hdc5  but thought it would wipe
> > > the partition clean and I don't want to start over if there is *any*
> > > hope of recovering it.
> > >
> > > Please, if anyone knows a way to recover this volume,  I would be
> > > extremely grateful for the help.
> > >
> > > Les Hazelton
> >
> > --
> >

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

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

Re: [linux-lvm] need help to recover my system

[Les Hazelton]

"Heinz J. Mauelshagen" wrote:
> 
> On Sun, Oct 01, 2000 at 11:42:59AM -0400, Les Hazelton wrote:
> > My kernel had LVM support compiled in, not as a module.  I had created an initrd but
> > may have not done that correctly.  I think the real problem was that the grub loader
> > was installed on the root "/" partition and not the "/boot" partition.  I had booted
> > the new configuration several times without problem until I deleted the original "/"
> > partition.  That's when I realized where the grub loader was installed.
> >
> > When I use linux fdisk I see the entry for hdc5 as Linux LVM (85) and if I do "cat
> > /proc/partitions"  there is an entry for /dev/hdc5.
> >
> > If, while running my test system with kernel 2.4.0, I run the pvcreate command for
> > /dev/hdc5 will that destroy the existing PV, VG, LVM content that is currently their?
> 
> Yes. You don't want to do that!

I didn't.  It just looked too dangerous 

> But it only allows you to do that using the "-ff" option of the
> pvcreate command. Without that it complains _because_ the physical volume
> still belongs to a volume group.
> 
> Could you supply the "pvscan -d" and the "vgscan -d" output from your test
> system to enable further investigation on why LVM doesn't find your volume
> group any longer?

I took two steps here. First, I thought some of the problems were
related to the 2.4.0 kernel so I backed it off and added an
lvm-2.2.16/17 patch I found referenced in the lvm mail archive. This
patch applied without error to the 2.2.17 kernel distributed on the
Mandrake 7.2b image. I configured it with "y" for lvm support and PROC
lvm data.

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@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"

vgchange -- unlocking logical volume manager
[root@farpt1 /root]# 

Not sure what I am missing here because the LVM support is linked with
the kernel so there is no module to load.

Les Hazelton

> Heinz
> 
> >
> > "Heinz J. Mauelshagen" wrote:
> >
> > > On Sat, Sep 30, 2000 at 11:02:36PM -0400, Les Hazelton wrote:
> > > > I had a Mandrake 7.1 system running the 2.2.17 kernel with LVM and
> > > > reiserfs patches applied.  I have a 15Gb partition on /dev/hdc5 which
> > > > was one large PV. It supports one VG which has the logical volumes for
> > > > /usr, /home, /var, etc... Everything except /boot and / which were on
> > > > the hda drive as plain ext2 file systems.
> > > >
> > > > I decided to move the root partition "/" to a logical volume on hdc5 and
> > > > all was going well until I deleted it from the ext2 system on hda6.
> > >
> > > How did you do that?
> > > Did you create an inital ram disk to load the lvm driver and activate
> > > the volume group?
> > > Otherwise you can't access your volume group(s) anyway from the /boot
> > > booted kernel.
> > >
> > > > So
> > > > now I have a perfectly good Linux system contained on the hdc5 PV which
> > > > I can't access.
> > > >
> > > > I have test system (Mandrake 7.2-b) on the hda drive.  It has the
> > > > 2.4.0-0.22 kernel distributed my Mandrake and I have been attempting to
> > > > recover using that system.  The problem is I keep getting these errors:
> > > >
> > > > ------------------------------------------------------------------------------
> > > > pvscan -- reading all physical volumes (this may take a while...)
> > > > pvscan -- ERROR "pv_read_all_pv(): lvm_dir_cache" reading physical
> > > > volumes
> > >
> > > This error means, that no (compatible) entries could be found either
> > > in /proc/partitions or, if /proc/partitions doesn't exist, in /dev.
> > >
> > > Please check that these sources are valid on your Mandrake 7.2-b test system
> > > and retry.
> > >
> > > >
> > > > [root@farpt1 /root]# vgscan -v
> > > > vgscan -- removing "/etc/lvmtab" and "/etc/lvmtab.d"
> > > > vgscan -- reading all physical volumes (this may take a while...)
> > > > vgscan -- no volume groups found
> > > > -------------------------------------------------------------------------------
> > > >
> > > > I was going to try a pvcreate for /dev/hdc5  but thought it would wipe
> > > > the partition clean and I don't want to start over if there is *any*
> > > > hope of recovering it.
> > > >
> > > > Please, if anyone knows a way to recover this volume,  I would be
> > > > extremely grateful for the help.
> > > >
> > > > Les Hazelton
> > >
> > > --
> > >
> 
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
> 
> Heinz Mauelshagen                                 Sistina Software Inc.
> Senior Consultant/Developer                       Bartningstr. 12
>                                                   64289 Darmstadt
>                                                   Germany
> Mauelshagen@Sistina.com                           +49 6151 7103 86
>                                                        FAX 7103 96
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

-- 
Les Hazelton
---------------------------------------------
Good journey, longevity and prosperity to all

Re: [linux-lvm] need help to recover my system

[Andreas Dilger]

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@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

Re: [linux-lvm] need help to recover my system

[Les Hazelton]

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.  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?  If I do that it will destroy the existing data.  It appears so
close to being recovered yet still so far away.

----------------------------
[root@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@farpt1 /root]# mount -t reiserfs /dev/vg01/usr /vg01/usr
mount: special device /dev/vg01/usr does not exist

-----------------------------------------
[root@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@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

Re: [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@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@farpt1 /root]# mount -t reiserfs /dev/vg01/usr /vg01/usr
> mount: special device /dev/vg01/usr does not exist
> 
> -----------------------------------------
> [root@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@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 --

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

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

Re: [linux-lvm] need help to recover my system

[Les Hazelton]

"Heinz J. Mauelshagen" wrote:
> 
> 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?

Yes,  that appears to have done it.  I could have sworn I did that
originally to create the /etc/lvmtab.d before I did the vgchange -ay.
Still, I just did vgscan again and now the /dev/vg01/xxx nodes are
there. It looks like vgscan was required to get the database established
so the other tools would run and again after the vgchange had activated
the VG to create the nodes.

[root@farpt1 lrh]# ls -l /dev/vg01
total 0
crw-r-----    1 root     root     109,   0 Oct  2 04:40 group
brw-r-----    1 root     root      58,   1 Oct  2 04:40 home
brw-r-----    1 root     root      58,   2 Oct  2 04:40 local
brw-r-----    1 root     root      58,   6 Oct  2 04:40 main
brw-r-----    1 root     root      58,   4 Oct  2 04:40 mp3
brw-r-----    1 root     root      58,   5 Oct  2 04:40 src
brw-r-----    1 root     root      58,   3 Oct  2 04:40 usr
brw-r-----    1 root     root      58,   0 Oct  2 04:40 var

Now the mount also works.

[root@farpt1 lrh]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/hda7             2.9G  2.8G  2.6M 100% /
/dev/hda8             2.9G  1.3G  1.5G  47% /Archives
/dev/hda1             2.0G  1.6G  449M  78% /mnt/win_c
/dev/sda5             2.0G  1.2G  803M  61% /mnt/win_c2
/dev/hda6             2.0G  387M  1.6G  19% /mnt/win_d
/dev/vg01/usr         2.5G  1.9G  574M  78% /vg01/usr
/dev/vg01/main        512M  321M  190M  63% /vg01/main
/dev/vg01/local       800M  600M  200M  75% /vg01/local
/dev/vg01/var         252M  117M  134M  47% /vg01/var
/dev/vg01/home       1020M  414M  606M  41% /vg01/home
/dev/vg01/src         600M  368M  232M  61% /vg01/src
/dev/vg01/mp3         1.5G  1.4G   98M  94% /vg01/mp3


Thank you all so very much for all your help.  You bailed me out of a
stupid mistake. While I don't have the old system running just yet, I
now have a real chance. I plan to copy the "/" partition
(/dev/vg01/main) back to the hda drive, modify its /etc/fstab and the
grub entries on the original /boot partition and go from there.

Andreas, thanks for pointing out the vgchange patch.  I really do
appreciate all the help you both have provided.

Les Hazelton

> 
> > 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@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@farpt1 /root]# mount -t reiserfs /dev/vg01/usr /vg01/usr
> > mount: special device /dev/vg01/usr does not exist
> >
> > -----------------------------------------
> > [root@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@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 --
> 
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
> 
> Heinz Mauelshagen                                 Sistina Software Inc.
> Senior Consultant/Developer                       Bartningstr. 12
>                                                   64289 Darmstadt
>                                                   Germany
> Mauelshagen@Sistina.com                           +49 6151 7103 86
>                                                        FAX 7103 96
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

-- 
Les Hazelton
---------------------------------------------
Good journey, longevity and prosperity to all

Re: [linux-lvm] need help to recover my system

[Les Hazelton]

I have my production system back again thanks to all the help provided
by Heinz and Andreas. It has been an interesting week of learning.

Once my test system could see the logical volumes I created an ext2fs
partition on /dev/hda9 and copied the content of the "/" logical volume
to it. I changed the /etc/fstab entry for "/" to match the new location.
Next I modified the /boot/grub/menu.lst entry to match the new location.

Once these steps were done I re-booted the system using a grub floppy
disk. I used the root, kernel and boot commands to boot the production
Linux 7.1 system. From there I reentered grub and used the root and
install commands to install grub on the /boot partition.

I re-booted the system at that point and it is running now with no
apparent ill effects. I don't think I will make any improvements for a
few days.  I need the rest ;-)

Heinz, Andreas,  Many thanks.

-- 

Good Journey, longevity and prosperity to all

Les Hazelton

Re: [linux-lvm] need help to recover my system

[Heinz J. Mauelshagen]

On Sun, Oct 01, 2000 at 10:49:31PM -0600, 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@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"):

Yes, it does.
I already inserted YOSHIDA Daisuke's code into my 0.9 develoment tree.

Heinz

> 
> 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


=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

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