[linux-lvm] online resize

[linux-lvm] online resize

[Michael Schulz]

Hi,

can please anybody tell me where I can found 
an aktual informaiton about LVM2 and the filesystems
which are currently support online resizing?

In th LVM Howto I can't find the needied informations.

Regards  

[linux-lvm] XFS Decreasing Size

[James Hammett]

I don't actually want to do this, but after expanding the XFS 
partition size  (using xfs_growfs )  of a Logical Volume and looking 
for the "BACKDOWN" information, I couldn't find a simple explanation 
for shrink the partition back down.

Is this possible with XFS, or does one need to use XFS Dump to 
migrate the data to another partition?

thanks,
James
-- 
----------------------------------------------------------------------------
"The proper function of man is to live, not to exist. I shall not 
waste my days in trying to prolong them. I shall use my time." (Jack 
London)

Re: [linux-lvm] XFS Decreasing Size

[Kevin P. Fleming]

James Hammett wrote:

> Is this possible with XFS, or does one need to use XFS Dump to migrate
> the data to another partition?

XFS does not currently support shrinking filesystems, only growing.

Re: [linux-lvm] online resize

[Gunther Clasen]

On Wed, Mar 15, 2006, Michael Schulz wrote:

> can please anybody tell me where I can found 
> an aktual informaiton about LVM2 and the filesystems
> which are currently support online resizing?

I use reiserfs for quite a number of years now and it seems to work
fine. You can resize the volume when it is mounted, although I prefer
unmounting it first if that is possible. It also shrinks, I believe even
online, but I don't do shrinking very often. (I have done, but
filesystems tend to grow rather than shrink.)

mkreiserfs
resize_reiserfs

Regards,

Gunther

RE: [linux-lvm] online resize

[Roger Lucas]

We use Reiser3 here and it can grow a volume whilst it is mounted, but you
have to unmount the volume before you can shrink it.

The man pages for resize_reiserfs indicate that it should be used on
unmounted volumes...

AFAIK, Reiser is the only filesystem in common use that allows volumes to be
reduced.

> -----Original Message-----
> From: linux-lvm-bounces@redhat.com [mailto:linux-lvm-bounces@redhat.com]
> On Behalf Of Gunther Clasen
> Sent: 16 March 2006 09:03
> To: LVM general discussion and development
> Subject: Re: [linux-lvm] online resize
> 
> On Wed, Mar 15, 2006, Michael Schulz wrote:
> 
> > can please anybody tell me where I can found
> > an aktual informaiton about LVM2 and the filesystems
> > which are currently support online resizing?
> 
> I use reiserfs for quite a number of years now and it seems to work
> fine. You can resize the volume when it is mounted, although I prefer
> unmounting it first if that is possible. It also shrinks, I believe even
> online, but I don't do shrinking very often. (I have done, but
> filesystems tend to grow rather than shrink.)
> 
> mkreiserfs
> resize_reiserfs
> 
> Regards,
> 
> Gunther
> 
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@redhat.com
> https://www.redhat.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/

RE: [linux-lvm] online resize

[Nate Carlson]

On Thu, 16 Mar 2006, Roger Lucas wrote:
> We use Reiser3 here and it can grow a volume whilst it is mounted, but 
> you have to unmount the volume before you can shrink it.
>
> The man pages for resize_reiserfs indicate that it should be used on 
> unmounted volumes...
>
> AFAIK, Reiser is the only filesystem in common use that allows volumes 
> to be reduced.

Note that Reiser4 no longer supports this.  :(

------------------------------------------------------------------------
| nate carlson | natecars@natecarlson.com | http://www.natecarlson.com |
|       depriving some poor village of its idiot since 1981            |
------------------------------------------------------------------------

Re: [linux-lvm] online resize

[David Brown]

On Thu, Mar 16, 2006 at 12:12:34PM -0600, Nate Carlson wrote:
> On Thu, 16 Mar 2006, Roger Lucas wrote:
> >We use Reiser3 here and it can grow a volume whilst it is mounted, but 
> >you have to unmount the volume before you can shrink it.
> >
> >The man pages for resize_reiserfs indicate that it should be used on 
> >unmounted volumes...
> >
> >AFAIK, Reiser is the only filesystem in common use that allows volumes 
> >to be reduced.
> 
> Note that Reiser4 no longer supports this.  :(

According to the wikipedia page on Reiser4
<http://en.wikipedia.org/wiki/Reiser4>, Namesys will add this if someone
pays them to.

ext2/3 has supported resizing for quite some time.

Dave Brown

Re: [linux-lvm] online resize

[Urs Thuermann]

"Roger Lucas" <roger@planbit.co.uk> writes:

> AFAIK, Reiser is the only filesystem in common use that allows volumes to be
> reduced.

ext2/3 can do that, too.  Since years.  But you have to unmount first.


urs

Re: [linux-lvm] online resize

[Zac Slade]

On Thursday 16 March 2006 07:08, Roger Lucas wrote:
> We use Reiser3 here and it can grow a volume whilst it is mounted, but you
> have to unmount the volume before you can shrink it.
>
> The man pages for resize_reiserfs indicate that it should be used on
> unmounted volumes...
reiser3, resizable online in two ways (growing only)
        1)resize_reiserfs /path/to/dev 
        2)mount -o remount,resize /path/to/dev
To shrink reiser3 filesystem it must be unmounted.

XFS, MUST be mounted to resize use xfs_grow /mount/point
JFS, resizable online with a mount -o remount,resize /path/to/dev
ext2/3, resizable offline reliably.  Online resize is a *very* experimental 
experiment.  Have good backups.

For a good reference if one is ever needed to give to a friend, relative or 
foe try http://www.tldp.org/HOWTO/LVM-HOWTO/extendlv.html

-- 
Zac Slade
krakrjak@volumehost.net
ICQ:1415282 YM:krakrjak AIM:ttyp99

Re: [linux-lvm] online resize

[Luca Berra]

On Sun, Mar 26, 2006 at 02:46:13AM -0600, Zac Slade wrote:
>ext2/3, resizable offline reliably.  Online resize is a *very* experimental 
>experiment.  Have good backups.

ext2/3 online resize is available as default in RedHat 4, and it just
works.

L.

-- 
Luca Berra -- bluca@comedia.it
        Communication Media & Services S.r.l.
 /"\
 \ /     ASCII RIBBON CAMPAIGN
  X        AGAINST HTML MAIL
 / \

Re: [linux-lvm] online resize

[Zac Slade]

On Sunday 26 March 2006 03:29, Luca Berra wrote:
> On Sun, Mar 26, 2006 at 02:46:13AM -0600, Zac Slade wrote:
> >ext2/3, resizable offline reliably.  Online resize is a *very*
> > experimental experiment.  Have good backups.
>
> ext2/3 online resize is available as default in RedHat 4, and it just
> works.
I'm glad that's the case for you.  If it works don't fix it.  However, from 
recent experience it is not release quality (especially for shrinking).
-- 
Zac Slade
krakrjak@volumehost.net
ICQ:1415282 YM:krakrjak AIM:ttyp99

Re: [linux-lvm] online resize

[Luca Berra]

On Sun, Mar 26, 2006 at 04:07:27AM -0600, Zac Slade wrote:
>On Sunday 26 March 2006 03:29, Luca Berra wrote:
>> On Sun, Mar 26, 2006 at 02:46:13AM -0600, Zac Slade wrote:
>> >ext2/3, resizable offline reliably.  Online resize is a *very*
>> > experimental experiment.  Have good backups.
>>
>> ext2/3 online resize is available as default in RedHat 4, and it just
>> works.
>I'm glad that's the case for you.  If it works don't fix it.  However, from 
>recent experience it is not release quality (especially for shrinking).
if you have any horror story, please share it, it will surely help other
users out there.

Regards,
L.

-- 
Luca Berra -- bluca@comedia.it
        Communication Media & Services S.r.l.
 /"\
 \ /     ASCII RIBBON CAMPAIGN
  X        AGAINST HTML MAIL
 / \

Re: [linux-lvm] online resize

[Zac Slade]

On Sunday 26 March 2006 04:26, Luca Berra wrote:
> if you have any horror story, please share it, it will surely help other
> users out there.
Distribution: Gentoo
Data: /home
Target: Resize from 1GiB to 800MiB (plenty of free space)
Filesystem: ext3
Method: ext2resize with kernel patches and latest e2fsprogs

Unmount /home in single user mode.  Resize using ext resizing utilities and 
spend the next 12 hours recovering inodes with fsck only to find a few 
hundred megs of data in /home/lost+found (with nonsensical names) and 
swearing off ext3 for mission critical data.

-- 
Zac Slade
krakrjak@volumehost.net
ICQ:1415282 YM:krakrjak AIM:ttyp99

Re: [linux-lvm] online resize

[Jan-Benedict Glaw]

[-- Attachment #1: Type: text/plain, Size: 1981 bytes --]

On Sun, 2006-03-26 05:36:59 -0600, Zac Slade <krakrjak@volumehost.net> wrote:
> On Sunday 26 March 2006 04:26, Luca Berra wrote:
> > if you have any horror story, please share it, it will surely help other
> > users out there.
> Distribution: Gentoo
> Data: /home
> Target: Resize from 1GiB to 800MiB (plenty of free space)
> Filesystem: ext3
> Method: ext2resize with kernel patches and latest e2fsprogs
> 
> Unmount /home in single user mode.  Resize using ext resizing utilities and 
> spend the next 12 hours recovering inodes with fsck only to find a few 
> hundred megs of data in /home/lost+found (with nonsensical names) and 
> swearing off ext3 for mission critical data.

Nice story, but as a bug report, this is mostly useless:

  * After umount, did you run an e2fsck -f?

  * Do you have a script(1) log of the whole session? (You'd probably
    have this started as a last resort log then you started the
    fsck'ing after the resize.)

  * What exactly is "ext resizing utilities"? Did you save a copy of
    it (incl. sources to find out about additionally applied patches?)

  * These nonsensical names you refer to are the file's inode numbers,
    in decimal. For mission-critical systems, it's wise to regularly
    get inode listings with filenames. Did you compare those inode
    numbers with your backups?

  * Did you prepare an image-backup of your 1GB container beforehand?
    Helps for easy recovery as well as error reproduction (esp.
    because 1GB isn't all that hard to store on one CD when there's
    plenty of free space, which can be made to compress very well.)

MfG, JBG

-- 
Jan-Benedict Glaw       jbglaw@lug-owl.de    . +49-172-7608481             _ O _
"Eine Freie Meinung in  einem Freien Kopf    | Gegen Zensur | Gegen Krieg  _ _ O
 für einen Freien Staat voll Freier Bürger"  | im Internet! |   im Irak!   O O O
ret = do_actions((curr | FREE_SPEECH) & ~(NEW_COPYRIGHT_LAW | DRM | TCPA));

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 189 bytes --]

Re: [linux-lvm] online resize

[Zac Slade]

On Sunday 26 March 2006 06:35, Jan-Benedict Glaw wrote:
> Nice story, but as a bug report, this is mostly useless:
This is not a bug report.  I did not file one (at the time I didn't have the 
time to track it).  And I needed my data then.  The time it would take to 
track the bug down, get a fix and get it running would have put me even 
further behind.  I remade the fs into reiser3 and restored the data.  I have 
had many successful resizes (but grow and shrink) since using reiser3.

>   * After umount, did you run an e2fsck -f?
Yes.

>   * Do you have a script(1) log of the whole session? (You'd probably
>     have this started as a last resort log then you started the
>     fsck'ing after the resize.)
No.  The session was not run through script(1).

>   * What exactly is "ext resizing utilities"? Did you save a copy of
>     it (incl. sources to find out about additionally applied patches?)
resize2fs.  I do not have a copy of the version used.

>   * These nonsensical names you refer to are the file's inode numbers,
>     in decimal. For mission-critical systems, it's wise to regularly
>     get inode listings with filenames. Did you compare those inode
>     numbers with your backups?
I know they are inode numbers, but they don't help you much in that situation.  
You think people keep inode listings with backups?  What a perfect world you 
live in.  I think it's not superflous information, but it is not a part of 
your average backup.  As a matter of fact I've not incountered a system that 
does this.  Sure you can do this on your own and it sort of makes sense.  
This just seems like a strange suggestion to me.

>   * Did you prepare an image-backup of your 1GB container beforehand?
>     Helps for easy recovery as well as error reproduction (esp.
>     because 1GB isn't all that hard to store on one CD when there's
>     plenty of free space, which can be made to compress very well.)
I did restore the data eventually.  I apologize if that was not clear.  I was 
frustrated that the tool did not perform as expected and it is something I 
should have followed up on with a bug report.  I should go back and do some 
experimenting with the current e2fsprogs and see if they behave better now.

-- 
Zac Slade
krakrjak@volumehost.net
ICQ:1415282 YM:krakrjak AIM:ttyp99

Re: [linux-lvm] online resize

[Jan-Benedict Glaw]

[-- Attachment #1: Type: text/plain, Size: 2294 bytes --]

On Sun, 2006-03-26 23:50:53 -0600, Zac Slade <krakrjak@volumehost.net> wrote:
> >   * Do you have a script(1) log of the whole session? (You'd probably
> >     have this started as a last resort log then you started the
> >     fsck'ing after the resize.)
> No.  The session was not run through script(1).

That's something I learned the hard way, too. Though that was not a
Linux session.

> >   * These nonsensical names you refer to are the file's inode numbers,
> >     in decimal. For mission-critical systems, it's wise to regularly
> >     get inode listings with filenames. Did you compare those inode
> >     numbers with your backups?
> I know they are inode numbers, but they don't help you much in that situation.  
> You think people keep inode listings with backups?  What a perfect world you 
> live in.  I think it's not superflous information, but it is not a part of 
> your average backup.  As a matter of fact I've not incountered a system that 
> does this.  Sure you can do this on your own and it sort of makes sense.  
> This just seems like a strange suggestion to me.

inode/filename listings are rarely heared of, but I have them at my
hands for the backups I drive. Learned that the hard way, too...
Again, not on a Linux box.

> >   * Did you prepare an image-backup of your 1GB container beforehand?
> >     Helps for easy recovery as well as error reproduction (esp.
> >     because 1GB isn't all that hard to store on one CD when there's
> >     plenty of free space, which can be made to compress very well.)
> I did restore the data eventually.  I apologize if that was not clear.  I was 
> frustrated that the tool did not perform as expected and it is something I 
> should have followed up on with a bug report.  I should go back and do some 
> experimenting with the current e2fsprogs and see if they behave better now.

So at least you had no data loss. That's most important.

MfG, JBG

-- 
Jan-Benedict Glaw       jbglaw@lug-owl.de    . +49-172-7608481             _ O _
"Eine Freie Meinung in  einem Freien Kopf    | Gegen Zensur | Gegen Krieg  _ _ O
 für einen Freien Staat voll Freier Bürger"  | im Internet! |   im Irak!   O O O
ret = do_actions((curr | FREE_SPEECH) & ~(NEW_COPYRIGHT_LAW | DRM | TCPA));

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 189 bytes --]