Hi Heinz,
it looks like the LVM snapshotting in 2.4 doesn't allow you
to create snapshots from anything else than the _first_ LV
in the VG...
I have run both the following command lines (after lvremoving
snap1, of course) and both of them give as a result that the
LV /dev/test_vg/swap ends up being the snapshotted filesystem ;(
# lvcreate -s -L100 -nsnap1 /dev/test_vg/test
# lvcreate -s -L100 -nsnap1 /dev/test_vg/swap
# cat /proc/lvm
LVM driver version 0.8final (15/02/2000)
<snip VG/PV info>
LVs: [AWDL ] swap 122880 /30 1x open
[AWDL ] test 204800 /50 1x open
[ARDL ] snap1 122880 /30 close
It looks like somewhere in either the utilities or the
kernel, the argument of which LV to snapshot gets mangled...
Oh, I'm using version 0.8final of the LVM utities.
regards,
Rik
--
"What you're running that piece of shit Gnome?!?!"
-- Miguel de Icaza, UKUUG 2000
http://www.conectiva.com/ http://www.surriel.com/
On Thu, 26 Oct 2000, Rik van Riel wrote:
> it looks like the LVM snapshotting in 2.4 doesn't allow you
> to create snapshots from anything else than the _first_ LV
> in the VG...
OK, I reproduced it in 2.2 as well ... ;(
> I have run both the following command lines (after lvremoving
> snap1, of course) and both of them give as a result that the
> LV /dev/test_vg/swap ends up being the snapshotted filesystem ;(
>
> # lvcreate -s -L100 -nsnap1 /dev/test_vg/test
> # lvcreate -s -L100 -nsnap1 /dev/test_vg/swap
>
> # cat /proc/lvm
> LVM driver version 0.8final (15/02/2000)
>
> <snip VG/PV info>
>
> LVs: [AWDL ] swap 122880 /30 1x open
> [AWDL ] test 204800 /50 1x open
> [ARDL ] snap1 122880 /30 close
>
> It looks like somewhere in either the utilities or the
> kernel, the argument of which LV to snapshot gets mangled...
> Oh, I'm using version 0.8final of the LVM utities.
>
> regards,
>
> Rik
> --
> "What you're running that piece of shit Gnome?!?!"
> -- Miguel de Icaza, UKUUG 2000
>
> http://www.conectiva.com/ http://www.surriel.com/
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to [email protected]
> Please read the FAQ at http://www.tux.org/lkml/
>
Rik
--
"What you're running that piece of shit Gnome?!?!"
-- Miguel de Icaza, UKUUG 2000
http://www.conectiva.com/ http://www.surriel.com/
Hi Rik,
I can't reproduce it on my box.
Could you provide a "lvcreate -d" output of what you did to help
me to dig into that one.
Did somebody else out there face the same 0.8final snapshot weirdness?
On Thu, Oct 26, 2000 at 04:36:37PM -0200, Rik van Riel wrote:
> Hi Heinz,
>
> it looks like the LVM snapshotting in 2.4 doesn't allow you
> to create snapshots from anything else than the _first_ LV
> in the VG...
>
> I have run both the following command lines (after lvremoving
> snap1, of course) and both of them give as a result that the
> LV /dev/test_vg/swap ends up being the snapshotted filesystem ;(
>
> # lvcreate -s -L100 -nsnap1 /dev/test_vg/test
> # lvcreate -s -L100 -nsnap1 /dev/test_vg/swap
>
> # cat /proc/lvm
> LVM driver version 0.8final (15/02/2000)
>
> <snip VG/PV info>
>
> LVs: [AWDL ] swap 122880 /30 1x open
> [AWDL ] test 204800 /50 1x open
> [ARDL ] snap1 122880 /30 close
>
> It looks like somewhere in either the utilities or the
> kernel, the argument of which LV to snapshot gets mangled...
> Oh, I'm using version 0.8final of the LVM utities.
>
> regards,
>
> Rik
> --
> "What you're running that piece of shit Gnome?!?!"
> -- Miguel de Icaza, UKUUG 2000
>
> http://www.conectiva.com/ http://www.surriel.com/
--
Regards,
Heinz -- The LVM guy --
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Heinz Mauelshagen Sistina Software Inc.
Senior Consultant/Developer Bartningstr. 12
64289 Darmstadt
Germany
[email protected] +49 6151 7103 86
FAX 7103 96
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
On Thu, Oct 26, 2000 at 06:34:48PM -0200, Rik van Riel wrote:
> On Thu, 26 Oct 2000, Rik van Riel wrote:
>
> > it looks like the LVM snapshotting in 2.4 doesn't allow you
> > to create snapshots from anything else than the _first_ LV
> > in the VG...
>
> OK, I reproduced it in 2.2 as well ... ;(
Which 2.2.x? LVM isn't supported in 2.2.18pre17 or any other previous version.
For some irrelevant reason I always test snapshotting on a LV with minor
number > 1 and the kernel side definitely works with 2.2.18pre17aa1:
laser:/home/andrea # ls -l /dev/vg1/lv*
brw-r----- 1 root root 58, 0 Oct 27 2000 /dev/vg1/lv0
brw-r----- 1 root root 58, 1 Oct 27 2000 /dev/vg1/lv1
laser:/home/andrea # lvcreate -s -n lv1-snap /dev/vg1/lv1 -L 400M
lvcreate -- INFO: using default snapshot chunk size of 64 KB
lvcreate -- doing automatic backup of "vg1"
lvcreate -- logical volume "/dev/vg1/lv1-snap" successfully created
laser:/home/andrea # lvremove -f /dev/vg1/lv1-snap
lvremove -- doing automatic backup of volume group "vg1"
lvremove -- logical volume "/dev/vg1/lv1-snap" successfully removed
laser:/home/andrea #
Andrea
On Fri, 27 Oct 2000, Andrea Arcangeli wrote:
> On Thu, Oct 26, 2000 at 06:34:48PM -0200, Rik van Riel wrote:
> > On Thu, 26 Oct 2000, Rik van Riel wrote:
> >
> > > it looks like the LVM snapshotting in 2.4 doesn't allow you
> > > to create snapshots from anything else than the _first_ LV
> > > in the VG...
> >
> > OK, I reproduced it in 2.2 as well ... ;(
>
> Which 2.2.x? LVM isn't supported in 2.2.18pre17 or any other previous version.
>
> For some irrelevant reason I always test snapshotting on a LV with minor
> number > 1 and the kernel side definitely works with 2.2.18pre17aa1:
>
> laser:/home/andrea # ls -l /dev/vg1/lv*
> brw-r----- 1 root root 58, 0 Oct 27 2000 /dev/vg1/lv0
> brw-r----- 1 root root 58, 1 Oct 27 2000 /dev/vg1/lv1
> laser:/home/andrea # lvcreate -s -n lv1-snap /dev/vg1/lv1 -L 400M
> lvcreate -- INFO: using default snapshot chunk size of 64 KB
> lvcreate -- doing automatic backup of "vg1"
> lvcreate -- logical volume "/dev/vg1/lv1-snap" successfully created
>
> laser:/home/andrea # lvremove -f /dev/vg1/lv1-snap
> lvremove -- doing automatic backup of volume group "vg1"
> lvremove -- logical volume "/dev/vg1/lv1-snap" successfully removed
>
> laser:/home/andrea #
With LVM from 2.2.18aa kernels (I dont exactly remember which one)
On Thu, Oct 26, 2000 at 11:37:07PM +0000, Heinz J. Mauelshagen wrote:
>
> Hi Rik,
>
> I can't reproduce it on my box.
>
> Could you provide a "lvcreate -d" output of what you did to help
> me to dig into that one.
>
> Did somebody else out there face the same 0.8final snapshot weirdness?
Yes. I have the same problem Rik has. A debug printf just before the
ioctl in lv_create_remove gives the right ->lv_snapshot_minor.
A debug printk in lvm_do_lv_create just at the beginning has
->lv_snapshot_minor _always_ = 0.
This happens with the 0.8final utils, both with and without additional
patches. Andrea's lvm-tools-aa-20000119 are ok.
Look like a structure mis-match to me, although lv_v2_t is the same for
all tools.
Christoph
--
Always remember that you are unique. Just like everyone else.
On Thu, Oct 26, 2000 at 09:10:06PM -0200, Marcelo Tosatti wrote:
> With LVM from 2.2.18aa kernels (I dont exactly remember which one)
Ok, nothing relevant is recently changed there so it should be an userspace
issue.
Andrea
Rik writes:
> it looks like the LVM snapshotting in 2.4 doesn't allow you
> to create snapshots from anything else than the _first_ LV
> in the VG...
>
> It looks like somewhere in either the utilities or the
> kernel, the argument of which LV to snapshot gets mangled...
> Oh, I'm using version 0.8final of the LVM utities.
One thing to notice is that the 0.8final tools have several bugs in them.
Most of these bugs are fixed in my user tools SRPM at:
ftp://ftp.stelias.com/pub/adilger/
If you are compiling on a 2.4 system, you need to patch the lvm.h file
with the following patch, so that you can use the same header in kernel
and user space. One of the problems with snapshots is that there is a
char __unused
field added in the 2.4 kernel sources that is not in the header for the
user tools, and this is only affecting snapshots, so it is best to use
the same header for both. This patch should probably be added to the
stock 2.4 kernel...
Give my user tools a try (if you aren't doing so already), to ensure
you aren't hitting a known bug, and the lvm.h patch so you aren't
having trouble with struct parsing between kernel and user space.
Cheers, Andreas
------------ patch to make 2.4 lvm.h usable from LVM user tools ---------
--- linux-2.4.0-test10-pre5/include/linux/lvm.h Thu Oct 26 18:43:42 2000
+++ linux/include/linux/lvm.h Thu Oct 26 18:39:13 2000
@@ -49,6 +50,8 @@
* 08/12/1999 - changed LVM_LV_SIZE_MAX macro to reflect current 1TB limit
* 01/01/2000 - extended lv_v2 core structure by wait_queue member
* 12/02/2000 - integrated Andrea Arcagnelli's snapshot work
+ * 18/02/2000 - seperated user and kernel space parts by
+ * #ifdef them with __KERNEL__
*
*/
@@ -56,7 +59,9 @@
#ifndef _LVM_H_INCLUDE
#define _LVM_H_INCLUDE
-#define _LVM_H_VERSION "LVM 0.8final (15/2/2000)"
+#define _LVM_H_VERSION "LVM 0.8final (22/02/2000)"
+
+#include <linux/version.h>
/*
* preprocessor definitions
@@ -64,8 +69,9 @@
/* if you like emergency reset code in the driver */
#define LVM_TOTAL_RESET
+#ifdef __KERNEL__
#define LVM_GET_INODE
-#undef LVM_HD_NAME
+#define LVM_HD_NAME
/* lots of debugging output (see driver source)
#define DEBUG_LVM_GET_INFO
@@ -80,20 +86,19 @@
#define DEBUG_KFREE
*/
-#include <linux/version.h>
-
-#ifndef __KERNEL__
-#define ____NOT_KERNEL____
+#include <linux/kdev_t.h>
+#include <linux/list.h>
+#else
#define __KERNEL__
-#endif
#include <linux/kdev_t.h>
-#ifdef ____NOT_KERNEL____
-#undef ____NOT_KERNEL____
+#include <linux/list.h>
#undef __KERNEL__
-#endif
+#endif /* #ifndef __KERNEL__ */
+#include <asm/types.h>
#include <linux/major.h>
+#ifdef __KERNEL__
#if LINUX_VERSION_CODE >= KERNEL_VERSION ( 2, 3 ,0)
#include <linux/spinlock.h>
#else
@@ -101,6 +106,8 @@
#endif
#include <asm/semaphore.h>
+#endif /* #ifdef __KERNEL__ */
+
#include <asm/page.h>
#if !defined ( LVM_BLK_MAJOR) || !defined ( LVM_CHAR_MAJOR)
@@ -125,7 +132,7 @@
#define pv_disk_t pv_disk_v1_t
#define lv_disk_t lv_disk_v1_t
#define vg_disk_t vg_disk_v1_t
-#define lv_exception_t lv_v2_exception_t
+#define lv_block_exception_t lv_block_exception_v1_t
#endif
@@ -220,7 +227,7 @@
LVM_TIMESTAMP_DISK_SIZE)
/* now for the dynamically calculated parts of the VGDA */
-#define LVM_LV_DISK_OFFSET(a, b) ( (a)->lv_on_disk.base + sizeof ( lv_t) * b)
+#define LVM_LV_DISK_OFFSET(a, b) ( (a)->lv_on_disk.base + sizeof ( lv_disk_t) * b)
#define LVM_DISK_SIZE(pv) ( (pv)->pe_on_disk.base + \
(pv)->pe_on_disk.size)
#define LVM_PE_DISK_OFFSET(pe, pv) ( pe * pv->pe_size + \
@@ -386,8 +392,7 @@
kdev_t rdev_org;
ulong rsector_new;
kdev_t rdev_new;
-} lv_block_exception_t;
-
+} lv_block_exception_v1_t;
/* disk stored pe information */
typedef struct
@@ -597,10 +558,14 @@
__u32 lv_remap_end;
__u32 lv_chunk_size;
__u32 lv_snapshot_minor;
+#ifdef __KERNEL__
struct kiobuf * lv_iobuf;
struct semaphore lv_snapshot_sem;
struct list_head * lv_snapshot_hash_table;
- unsigned long lv_snapshot_hash_mask;
+ ulong lv_snapshot_hash_mask;
+#else
+ char dummy[200];
+#endif
} lv_v2_t;
/* disk */
--
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
On Fri, Oct 27, 2000 at 01:53:08AM +0200, Christoph Hellwig wrote:
> Look like a structure mis-match to me, although lv_v2_t is the same for
> all tools.
Sorry I was wrong. The __unused field is missing.
Yet another reason for an official 0.8 maintaince release ;)
Christoph
--
Always remember that you are unique. Just like everyone else.
On Fri, 27 Oct 2000, Andrea Arcangeli wrote:
> For some irrelevant reason I always test snapshotting on a LV with minor
> number > 1 and the kernel side definitely works with 2.2.18pre17aa1:
>
> laser:/home/andrea # ls -l /dev/vg1/lv*
> brw-r----- 1 root root 58, 0 Oct 27 2000 /dev/vg1/lv0
> brw-r----- 1 root root 58, 1 Oct 27 2000 /dev/vg1/lv1
> laser:/home/andrea # lvcreate -s -n lv1-snap /dev/vg1/lv1 -L 400M
> lvcreate -- INFO: using default snapshot chunk size of 64 KB
> lvcreate -- doing automatic backup of "vg1"
> lvcreate -- logical volume "/dev/vg1/lv1-snap" successfully created
>
> laser:/home/andrea # lvremove -f /dev/vg1/lv1-snap
> lvremove -- doing automatic backup of volume group "vg1"
> lvremove -- logical volume "/dev/vg1/lv1-snap" successfully removed
Have you checked if the CONTENT of the snapshot is indeed
the right LV and not the other one?
(I get the same "success" messages as what you cut'n'pasted
above, but find that the wrong LV has been snapshotted when
I look at the actual snapshot)
regards,
Rik
--
"What you're running that piece of shit Gnome?!?!"
-- Miguel de Icaza, UKUUG 2000
http://www.conectiva.com/ http://www.surriel.com/
On Fri, Oct 27, 2000 at 11:32:06AM -0200, Rik van Riel wrote:
> Have you checked if the CONTENT of the snapshot is indeed
> the right LV and not the other one?
laser:~ # mke2fs /dev/vg1/lv1 &>/dev/null
laser:~ # mount /dev/vg1/lv1 /mnt
laser:~ # >/mnt/ciao
laser:~ # ls /mnt
. .. ciao lost+found
laser:~ # umount /mnt
laser:~ # lvcreate -s -n lv1-snap /dev/vg1/lv1 -L 400M
lvcreate -- INFO: using default snapshot chunk size of 64 KB
lvcreate -- doing automatic backup of "vg1"
lvcreate -- logical volume "/dev/vg1/lv1-snap" successfully created
laser:~ # mount /dev/vg1/lv1 /mnt
laser:~ # rm /mnt/ciao
laser:~ # umount /mnt
laser:~ # mount /dev/vg1/lv1-snap /mnt
mount: block device /dev/vg1/lv1-snap is write-protected, mounting read-only
laser:~ # ls /mnt/
. .. ciao lost+found
laser:~ #
Andrea
On Fri, 27 Oct 2000, Andrea Arcangeli wrote:
> On Fri, Oct 27, 2000 at 11:32:06AM -0200, Rik van Riel wrote:
> > Have you checked if the CONTENT of the snapshot is indeed
> > the right LV and not the other one?
>
> laser:~ # mke2fs /dev/vg1/lv1 &>/dev/null
> laser:~ # mount /dev/vg1/lv1 /mnt
> laser:~ # >/mnt/ciao
> laser:~ # ls /mnt
> . .. ciao lost+found
> laser:~ # umount /mnt
> laser:~ # lvcreate -s -n lv1-snap /dev/vg1/lv1 -L 400M
> lvcreate -- INFO: using default snapshot chunk size of 64 KB
> lvcreate -- doing automatic backup of "vg1"
> lvcreate -- logical volume "/dev/vg1/lv1-snap" successfully created
>
> laser:~ # mount /dev/vg1/lv1 /mnt
> laser:~ # rm /mnt/ciao
> laser:~ # umount /mnt
> laser:~ # mount /dev/vg1/lv1-snap /mnt
> mount: block device /dev/vg1/lv1-snap is write-protected, mounting read-only
> laser:~ # ls /mnt/
> . .. ciao lost+found
> laser:~ #
OK, good. I guess that means that the lvmutils (even the
patched version in the RPM) are heavily broken ...
Andrea, could you send me the patches you use to make your
LVM utilities work? Then we'll be able to put together at
least one working LVM utilities version ;)
Heinz, how about releasing a 0.8.1 version of the utilities
so that there is something WORKING out there? Not having
working LVM utilities available is an utter disgrace when
all the code to make it work is just available...
regards,
Rik
--
"What you're running that piece of shit Gnome?!?!"
-- Miguel de Icaza, UKUUG 2000
http://www.conectiva.com/ http://www.surriel.com/
On Fri, Oct 27, 2000 at 11:55:03AM -0200, Rik van Riel wrote:
> Andrea, could you send me the patches you use to make your
> LVM utilities work? Then we'll be able to put together at
ftp://ftp.suse.com/pub/suse/i386/7.0/suse/zq1/lvm.spm
Andrea
On Fri, Oct 27, 2000 at 11:55:03AM -0200, Rik van Riel wrote:
> On Fri, 27 Oct 2000, Andrea Arcangeli wrote:
> > On Fri, Oct 27, 2000 at 11:32:06AM -0200, Rik van Riel wrote:
> > > Have you checked if the CONTENT of the snapshot is indeed
> > > the right LV and not the other one?
> >
> > laser:~ # mke2fs /dev/vg1/lv1 &>/dev/null
> > laser:~ # mount /dev/vg1/lv1 /mnt
> > laser:~ # >/mnt/ciao
> > laser:~ # ls /mnt
> > . .. ciao lost+found
> > laser:~ # umount /mnt
> > laser:~ # lvcreate -s -n lv1-snap /dev/vg1/lv1 -L 400M
> > lvcreate -- INFO: using default snapshot chunk size of 64 KB
> > lvcreate -- doing automatic backup of "vg1"
> > lvcreate -- logical volume "/dev/vg1/lv1-snap" successfully created
> >
> > laser:~ # mount /dev/vg1/lv1 /mnt
> > laser:~ # rm /mnt/ciao
> > laser:~ # umount /mnt
> > laser:~ # mount /dev/vg1/lv1-snap /mnt
> > mount: block device /dev/vg1/lv1-snap is write-protected, mounting read-only
> > laser:~ # ls /mnt/
> > . .. ciao lost+found
> > laser:~ #
>
> OK, good. I guess that means that the lvmutils (even the
> patched version in the RPM) are heavily broken ...
As i mentioned before: i wasn't able to reproduce your problem on any of
my systems. It work just fine with 0.8final and in 0.9 as weel.
Did anybody else beside Rik face a problem with snapshots _not_ referring
to the original logical volume they where created for?
>
> Andrea, could you send me the patches you use to make your
> LVM utilities work? Then we'll be able to put together at
> least one working LVM utilities version ;)
>
> Heinz, how about releasing a 0.8.1 version of the utilities
> so that there is something WORKING out there? Not having
> working LVM utilities available is an utter disgrace when
> all the code to make it work is just available...
I don't have any complaints so far about similar snapshot malfunctions
you mentioned, Rik.
That said it is overemphasis to say, that the LVM utilities
are not working.
IMHO Andreas Dilger's LVM 0.8 backport to kernel 2.2 should be o.k. for
most of the cases.
I'ld like to have 0.9 to do the integtration of the available patches
which will be released in november.
>
> regards,
>
> Rik
> --
> "What you're running that piece of shit Gnome?!?!"
> -- Miguel de Icaza, UKUUG 2000
>
> http://www.conectiva.com/ http://www.surriel.com/
--
Regards,
Heinz -- The LVM guy --
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Heinz Mauelshagen Sistina Software Inc.
Senior Consultant/Developer Bartningstr. 12
64289 Darmstadt
Germany
[email protected] +49 6151 7103 86
FAX 7103 96
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
On Sat, 28 Oct 2000, Heinz J. Mauelshagen wrote:
> > OK, good. I guess that means that the lvmutils (even the
> > patched version in the RPM) are heavily broken ...
>
> As i mentioned before: i wasn't able to reproduce your problem on any of
> my systems. It work just fine with 0.8final and in 0.9 as weel.
>
> Did anybody else beside Rik face a problem with snapshots _not_
> referring to the original logical volume they where created for?
There's a missing item in the _data structure declaration_
in the header file that prevents userspace from passing
the right LV argument to the kernel, resulting in the kernel
always making a snapshot of LV #0.
You may have written LVM, but that doesn't excuse you from
checking your facts ;)
regards,
Rik
--
"What you're running that piece of shit Gnome?!?!"
-- Miguel de Icaza, UKUUG 2000
http://www.conectiva.com/ http://www.surriel.com/