4 Feb
2013
4 Feb
'13
12:30 p.m.
Hi,
Our new install is going pretty well. Thanks for all your help so far.
Not wanting me to have an easy life, the project manager has just thrown
me a curve-ball: The most recent generation of the current system in the
wild is built on fairly-new hardware and he's asked for all the last-gen
machines (Dell R210) to be returned to us for internal use. He wants me
to install the new Xen VM bundle on the Dell hardware. If I'd known
about this earlier-on, there are a few things I would have done slightly
differently.
The biggest problem I have right now is that the new machines have 300GB
drives in them and the Dells are 250GB. We use Clonezilla to image the
machines and it won't restore the drive (an ext /boot and an LVM PV)
from the 300GB drive to the 250 even though more than 50GB of the LVM PV
is unallocated (The LVs total in the low 200s of GBs in a 299GB PV) so
the LVs don't need resizing.
I think I need to either:
1) Find someone who is a Clonezilla god who can tell me how to make
Clonezilla shrink the PV using some of the advanced options.
2) Restore the image to one of our new test boxes, shrink the PV to
under 250GB and then make a new Clonezilla image from that.
I would value any of your input on how to achieve either of these
options without breaking something. I'm thinking option 2 will probably
be the one.
Thanks,
Paul.
4 Feb
4 Feb
1:13 p.m.
Hi Paul,
On Mon, Feb 04, 2013 at 12:30:53PM +0000, Paul Stimpson wrote:
I think I need to either:
1) Find someone who is a Clonezilla god who can tell me how to
make Clonezilla shrink the PV using some of the advanced options.
I don't know anything about CloneZilla I'm afraid, but…
2) Restore the image to one of our new test boxes,
shrink the PV
to under 250GB and then make a new Clonezilla image from that.
…shrinking a PV is easy.
- Boot a live distribution or rescue environment
- Shrink the filesystem on the LV and the LV along with it:
# lvresize --resizefs -L250G /dev/yourvg/yourlv
If you haven't got a recent enough LVM for it to support
--resizefs, you'll have to do it as a resize2fs first (or
equivalent for your FS), followed by an lvresize.
- Shrink the PV to match, assuming your PV is /dev/sda1:
# pvresize /dev/sda1 --setphysicalvolumesize 250G
- HAVE BACKUPS
Finally you'll need to shrink the partition /dev/sda1 which will
involve deleting the partition and recreating it again smaller.
HAVE BACKUPS
This is the scariest part. You could use something like:
HAVE BACKUPS
# pvs --units s
To see the size of the (now shrunk) PV in sectors, so you can work
out how big to make the partition.
One trick I sometimes use to make it a little less terrifying is
to shrink the PV (and everything inside it) a bit smaller than I
need, shrink the partition, and then grow everything back to the
maximum it can be as that requires no guesswork over exact sector
numbers.
All of the resize commands without an explicit target size will
grow to maximum of their container.
So there you go, simple.
Cheers,
Andy
--
http://bitfolk.com/ -- No-nonsense VPS hosting
5 Feb
5 Feb
4:50 a.m.
Hello Andy,
On 04/02/13 13:13, Andy Smith wrote:
Hi Paul,
On Mon, Feb 04, 2013 at 12:30:53PM +0000, Paul Stimpson wrote:
You missed out a "HAVE BACKUPS" just about here.
I think I need to either:
1) Find someone who is a Clonezilla god who can tell me how to
make Clonezilla shrink the PV using some of the advanced options.
I don't know
anything about CloneZilla I'm afraid, but…
> 2) Restore the image to one of our new test boxes, shrink the PV
> to under 250GB and then make a new Clonezilla image from that. …shrinking a PV is easy.
But seriously, it's easy to forget just how powerful LVM is. Thank you
very much for this tutorial.
- Boot a live distribution or rescue environment
- Shrink the filesystem on the LV and the LV along with it:
# lvresize --resizefs -L250G /dev/yourvg/yourlv
If you haven't got a recent enough LVM for it to support
--resizefs, you'll have to do it as a resize2fs first (or
equivalent for your FS), followed by an lvresize.
- Shrink the PV to match, assuming your PV is /dev/sda1:
# pvresize /dev/sda1 --setphysicalvolumesize 250G
- HAVE BACKUPS
Finally you'll need to shrink the partition /dev/sda1 which will
involve deleting the partition and recreating it again smaller.
HAVE BACKUPS
This is the scariest part. You could use something like:
HAVE BACKUPS
# pvs --units s
To see the size of the (now shrunk) PV in sectors, so you can work
out how big to make the partition.
One trick I sometimes use to make it a little less terrifying is
to shrink the PV (and everything inside it) a bit smaller than I
need, shrink the partition, and then grow everything back to the
maximum it can be as that requires no guesswork over exact sector
numbers.
All of the resize commands without an explicit target size will
grow to maximum of their container.
So there you go, simple.
Cheers,
Andy
--
Regards,
Jan Henkins
4:42 p.m.
Thanks everyone.
I got it resized.
The donor machine was freshly imaged from or current development image
so backups were had before I even started :) *no partitions were harmed
in the making of this movie :)
I also found out that the new Parted Magic disc supports resizing LVM
containers as long as you deactivate them first :)
Cheers,
Paul.
5:24 p.m.
Hi Paul,
On Tue, Feb 05, 2013 at 04:42:21PM +0000, Paul Stimpson wrote:
I also found out that the new Parted Magic disc
supports resizing LVM
containers as long as you deactivate them first :)
That's interesting. You'd also have to deactivate them if doing it
on the command line, I think.
"Parted Magic" is a really silly name - it makes me think of
Partition Magic! I assume you are talking about this though:
http://www.linuxuser.co.uk/reviews/parted-magic-review
So is it GParted that did the resizing for you?
Cheers,
Andy
--
http://bitfolk.com/ -- No-nonsense VPS hosting
6:12 p.m.
On 05/02/13 17:24, Andy Smith wrote:
Hi Paul,
On Tue, Feb 05, 2013 at 04:42:21PM +0000, Paul Stimpson wrote:
Being LVM-aware, I think the Parted Magic disc makes all VGs active at boot.
I also found out that the new Parted Magic disc
supports resizing LVM
containers as long as you deactivate them first :)
That's interesting.
You'd also have to deactivate them if doing it
on the command line, I think. "Parted Magic" is a really silly name - it
makes me think of
Partition Magic! I assume you are talking about this though:
http://www.linuxuser.co.uk/reviews/parted-magic-review
The same...
So is it GParted that did the resizing for you?
I used your instructions to resize the PV on the host then used Parted
Magic to shrink the logical partition and the extended partition it was
contained in to match the new size of the PV. (/dev/sda2 was the
extended, containing logical partition /dev/sda5 that had been given LVM
love with pvcreate)
The newest version of Gparted (as on the CD) is LVM-ready and checks
that none of the extents are used when shrinking a container partition.
It won't let you chop the end off an LV.
Cheers,
Paul.
4091
days inactive
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5 comments
3 participants
participants (3)
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Andy Smith -
Jan Henkins -
Paul Stimpson