[linux-lvm] Help: LVM on top of SW RAID0+1

[linux-lvm] Help: LVM on top of SW RAID0+1

[Ian E. Morgan]

Current config:

md1: raid0 of hda3, hdb3
md2: raid0 of hdc3, hdd3
md3: raid1 of md1, md2

Situation:

md1 was created first, and is currently one big PV in VG "foo".

md2 was created identically to md1, and then md3 was created causing md2 to
be synced to be identical to md1.

I would now like VG "foo" to use md3 instead of md1.

I tried:

# vgexport foo
# vgimport foo /dev/md3


This seemed to suceed, but vgdisplay says that VG "foo" is still only using
PV md1.

It seems that pvscan and friends see md[123] all as belonging to VG "foo".

How do I make LVM ignore md1 and md2, and force only md3 to be used on VG
"foo"?


Regards,
Ian Morgan

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Re: [linux-lvm] Help: LVM on top of SW RAID0+1

[Jon Bendtsen]

"Ian E. Morgan" wrote:
> 
> Current config:
> 
> md1: raid0 of hda3, hdb3
> md2: raid0 of hdc3, hdd3
> md3: raid1 of md1, md2

hmm. I tried various combinations of raid0 and raid1 ontop
of each other. One combination had a REALLY REALLY severe
performance penalty.


> md1 was created first, and is currently one big PV in VG "foo".
> 
> md2 was created identically to md1, and then md3 was created causing md2 to
> be synced to be identical to md1.
> 
> I would now like VG "foo" to use md3 instead of md1.
> 
> I tried:
> 
> # vgexport foo
> # vgimport foo /dev/md3
> 
> This seemed to suceed, but vgdisplay says that VG "foo" is still only using
> PV md1.
> 
> It seems that pvscan and friends see md[123] all as belonging to VG "foo".
> 
> How do I make LVM ignore md1 and md2, and force only md3 to be used on VG
> "foo"?

shut down the raid.
use only md1.
Make md2 and md3, with md1 MARKED AS FAILED.
create new VG, move data.
mark md1 okay, and include it into md3 with mdadm/raidhotadd




JonB

Re: [linux-lvm] Help: LVM on top of SW RAID0+1

[Steven Lembark]

-- Jon Bendtsen <jon+lvm@silicide.dk>

> "Ian E. Morgan" wrote:
>>
>> Current config:
>>
>> md1: raid0 of hda3, hdb3
>> md2: raid0 of hdc3, hdd3
>> md3: raid1 of md1, md2
>
> hmm. I tried various combinations of raid0 and raid1 ontop
> of each other. One combination had a REALLY REALLY severe
> performance penalty.

Why would you want to use raid0 with LVM? You can combine
the mirrors into a VG and distribute the space out using
LVM in the first place. You also have the option of using
striping for performance if works out with the software mirrors.



--
Steven Lembark                               2930 W. Palmer
Workhorse Computing                       Chicago, IL 60647
                                            +1 888 359 3508

Re: [linux-lvm] Help: LVM on top of SW RAID0+1

[jon+lvm]

On Sat, Mar 15, 2003 at 01:57:52PM -0600, Steven Lembark wrote:
> 
> 
> -- Jon Bendtsen <jon+lvm@silicide.dk>

[cut]

> >hmm. I tried various combinations of raid0 and raid1 ontop
> >of each other. One combination had a REALLY REALLY severe
> >performance penalty.
> 
> Why would you want to use raid0 with LVM? You can combine
> the mirrors into a VG and distribute the space out using
> LVM in the first place. You also have the option of using
> striping for performance if works out with the software mirrors.

You cant resize striped LV's. (AFAIR).




JonB

[linux-lvm] Debian and LVM at the begin of the installation prozess

[Stefan Feeser]

Hi all,

I am a beginner with LVM and Debian. I would like to install debian and "put" 
the hole disks in the LVM. At my system I would like to stripe-mirror (RAID 
10) my two disks (IDE). Because the hardware is not the newest one I have to 
do the installation with bootdisks.

My question is how I can create a volume group and so on during the 
installation prozess.

I have tested this but Debian always present his installation tool. I 
downloaded debian installation disks and the device drivers but I always see 
the installation tool. After that the next steps will be to configure 
language, etc., and, after that I have to create a swap partition and than an 
root partition. A LVM filesystem I can't create.

Sorry about my, I am sure, stupid questions and my bad english.

Thanks and regards

Stefan

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Stefan Feeser
+++++++++++++++++++++++++++++++++++++++++++
have a look to
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Re: [linux-lvm] Debian and LVM at the begin of the installation prozess

[shsp0058]

Quoting Stefan Feeser <stefan.feeser@felino.de>:

> Hi all,
> 
> I am a beginner with LVM and Debian. I would like to install debian and
> "put" 
> the hole disks in the LVM. At my system I would like to stripe-mirror
> (RAID 
> 10) my two disks (IDE). Because the hardware is not the newest one I
> have to 
> do the installation with bootdisks.
> 
> My question is how I can create a volume group and so on during the 
> installation prozess.
> 
> I have tested this but Debian always present his installation tool. I 
> downloaded debian installation disks and the device drivers but I always
> see 
> the installation tool. After that the next steps will be to configure 
> language, etc., and, after that I have to create a swap partition and
> than an 
> root partition. A LVM filesystem I can't create.
> 
> Sorry about my, I am sure, stupid questions and my bad english.
> 
> Thanks and regards
> 
> Stefan

Hi Stefan,
the easiest way would be:
1. create a /boot partition
2. create 2 raids - one for lvm,
   the second for temporary installation
3. format the second raid & install debian on it,
4. create VG & LV's on the first raid, and trasfer 
   the temporary installation to it 
   i use:
   cd /
   find . -xdev | cpio -pm /mnt/newroot
5. modify fstab & lilo.conf to correspond to the new
   installation, rerun lilo
6. boot in the new installation, if everything is OK,
   you can create PV of the second raid(the temporary installation)
   and add it to your VG,extend your LV's and the FS on them
7. that was all :)

regards,

svetljo
 

RE: [linux-lvm] Debian and LVM at the begin of the installation prozess

[Jan H. van Gils]

>Quoting Stefan Feeser <stefan.feeser@felino.de>:
>
>> Hi all,
>> 

	Hi,

>> I am a beginner with LVM and Debian. I would like to install debian 
>> and "put" the hole disks in the LVM. At my system I would like to 
>> stripe-mirror (RAID
>> 10) my two disks (IDE). Because the hardware is not the newest one I
>> have to 
>> do the installation with bootdisks.
>> 
>> My question is how I can create a volume group and so on during the
>> installation prozess.
>> 
>> I have tested this but Debian always present his installation tool. I
>> downloaded debian installation disks and the device drivers 
>but I always
>> see 
>> the installation tool. After that the next steps will be to 
>configure 
>> language, etc., and, after that I have to create a swap partition and
>> than an 
>> root partition. A LVM filesystem I can't create.
>> 


Don't put / (root) on a logical Volume when using debian !

The kernels from debian package manager apt use the cramfs file system
for initrd.
When this is mounted during boot LVM can't write lvmtab on /etc because
The cramfs is a read-only filesystem.

Only when you rebuild the kernel, and don't use the kernels in the
package
manager you can make sure the initrd supports ext2 during boot.


>> Sorry about my, I am sure, stupid questions and my bad english.
>> 
>> Thanks and regards
>> 
>> Stefan

Good luck Jan

----
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Internet e-mail address JanVG@Knoware.NL
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Re: [linux-lvm] Debian and LVM at the begin of the installation prozess

[Stefan Feeser]

Am Sonntag, 16. M�rz 2003 10:19 schrieb Jan H. van Gils:
> >Quoting Stefan Feeser <stefan.feeser@felino.de>:
> >> Hi all,
>
> 	Hi,

Hi,

thanks for your help! It seems that I haven' t understood something! I thougt 
that LVM is a kernel builtin, so that I can create logical volumes from the 
begin (my idea is to load a kernel, for example the 2.4 Linuxkernel from 
Debian Bootdisks (Today I haven' t found a Bootdiskversion with which I have 
the possibility to work with LVM after loading the kernel) in the RAM, and 
after that I create locial volumes and so on). Is this possible and if it is, 
please could you tell me how?

My main problem is that I don't want to create some "normal" partitions (If 
root should be an normal one is that ok). I have had a one week seminar with 
the Veritas LVM and I think that it is possible to load the LVM Module after 
loading the, for example Solaris, kernel and start to create my locial 
partions.

So with Linux, I want do the same. Start a kernel, install the LVM-Modules 
(could you explain how I can do this manually?) and than I go forwards with 
logical partions, etc.

> >> Thanks and regards
> >>
> >> Stefan
>
> Good luck Jan

A "servus" from bavarian to all;-))

Stefan

Re: [linux-lvm] Help: LVM on top of SW RAID0+1

[Alasdair G Kergon]

On Sat, Mar 15, 2003 at 11:38:16PM +0100, jon+lvm@silicide.dk wrote:
> You cant resize striped LV's. (AFAIR).

Unless you upgrade to LVM2.
 
Alasdair
-- 
agk@uk.sistina.com

Re: [linux-lvm] Help: LVM on top of SW RAID0+1

[Heinz J . Mauelshagen]

On Sun, Mar 16, 2003 at 07:48:09PM +0000, Alasdair G Kergon wrote:
> On Sat, Mar 15, 2003 at 11:38:16PM +0100, jon+lvm@silicide.dk wrote:
> > You cant resize striped LV's. (AFAIR).
> 
> Unless you upgrade to LVM2.

Well,
LVM1 limits a stripe to a PV. So growing a striped LV is limited by
the PV size. The only way to grow a striped LV in LVM1 in case one of
its stripes hits the PV size is to pvmove the stripe to a larger PV.

LVM2 doesn't have such constraint any longer :)

>  
> Alasdair
> -- 
> agk@uk.sistina.com
> 
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/

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Re: [linux-lvm] Help: LVM on top of SW RAID0+1

[Steven Lembark]

> You cant resize striped LV's. (AFAIR).

You can.


--
Steven Lembark                               2930 W. Palmer
Workhorse Computing                       Chicago, IL 60647
                                            +1 888 359 3508

Re: [linux-lvm] Debian and LVM at the begin of the installation prozess

[Stefan Feeser]

Am Samstag, 15. M�rz 2003 23:54 schrieb Stefan Feeser:
> Hi all,
Hi all,
>
> I am a beginner with LVM and Debian. I would like to install debian and
> "put" the hole disks in the LVM. At my system I would like to stripe-mirror
> (RAID 10) my two disks (IDE). Because the hardware is not the newest one I
> have to do the installation with bootdisks.
>
> My question is how I can create a volume group and so on during the
> installation prozess.
>
After reading some HoTows, I know how you can create LVM's during the 
installation process with disks with a debian system.

To work with lvm and debian on boot disks there are the following steps:

- Create a rescue.bin and a root.bin disk from 2.4 kernel. There you should 
have possibilities to work with LVM
- Download a file, which is called lar1440.bin from the internet and write it 
with cat lar1440.bin > /dev/fd0 to a seperate disk
- Boot your computer with the two boot disks and follow the installation menue 
til the step "partitionition the disks" (with the program cfdisk)
- Create a swap and a root partition on the normal way, the rest of space of 
the disk use type 8E, Linux LVM
- then switch to a second console (for example with ALT + F2)
- put the lar disk in your disk drive and type the command extdisk
- now you can work with LVM tools

Regards

Stefan