thr3ads.net - Xen users - [Xen-users] LVM partitions on PV domU [Jun 2009]

If this information is useful, please help other people find it:
Share via:

Matthias Reif

2009-Jun-18 00:22 UTC

[Xen-users] LVM partitions on PV domU

Hi All,

I am trying to install a 32-bit CentOS 5 paravirtualised domU based on
the instructions at
http://wiki.centos.org/HowTos/Xen/InstallingCentOSDomU.

I would like to allocate storage to the domU as a number of LVM
logical volumes instead of a single disk image.

Ie.

kernel = "/domx/boot/vmlinuz-xen-install"
ramdisk = "/domx/boot/initrd-xen-install"
extra = "text"

[...]

disk = [ ''phy:/dev/sage/root,xvda1,w'',
         ''phy:/dev/sage/usr,xvda2,w'',
         ''phy:/dev/sage/swap,xvda3,w'',
         ''phy:/dev/sage/tmp,xvda4,w'',
         ''phy:/dev/sage/var,xvda5,w'' ]
[...]

I was hoping the logical volumes would appear as partitions inside the
domU, but instead the installer recognises them as separate disk
devices and wants me to partition each of them, ie. xvda11, xvda21,
etc.

Is this expected behaviour?

Is it at all possible to pass LV partitions through to the domU as
partitions instead of disk devices?

dom0 = CentOS 5.2 64-bit
Xen = 3.3.1

Thank you.

Matthias

_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users

Matthias Reif

2009-Jun-18 04:38 UTC

head link

[Xen-users] LVM partitions on PV domU

Hi All,

I am trying to install a 32-bit CentOS 5 paravirtualised domU based on
the instructions at
http://wiki.centos.org/HowTos/Xen/InstallingCentOSDomU.

I would like to allocate storage to the domU as a number of LVM
logical volumes instead of a single disk image.

Ie.

kernel = "/domx/boot/vmlinuz-xen-install"
ramdisk = "/domx/boot/initrd-xen-install"
extra = "text"

[...]

disk = [ ''phy:/dev/sage/root,xvda1,w'',
        ''phy:/dev/sage/usr,xvda2,w'',
        ''phy:/dev/sage/swap,xvda3,w'',
        ''phy:/dev/sage/tmp,xvda4,w'',
        ''phy:/dev/sage/var,xvda5,w'' ]
[...]

I was hoping the logical volumes would appear as partitions inside the
domU, but instead the installer recognises them as separate disk
devices and wants me to partition each of them, ie. xvda11, xvda21,
etc.

Is this expected behaviour?

Is it at all possible to pass LV partitions through to the domU as
partitions instead of disk devices?

dom0 = CentOS 5.2 64-bit
Xen = 3.3.1

Thank you.

Matthias

_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users

Alan Lam

2009-Jun-18 04:42 UTC

head link

RE: [Xen-users] LVM partitions on PV domU

Hi,

 

You can pass a LVM partition (one) to the DomU as a disk (as you have
discovered). Then you can let the DomU partition it.

 

If you have a need to access the partitions of the DomU, in Dom0, then
you can make use of kpartx to access them.

 

Regards,

Alan

 

-----Original Message-----
From: Matthias Reif [mailto:matthreif@gmail.com] 
Sent: Thursday, 18 June 2009 2:38 PM
To: xen-users@lists.xensource.com
Subject: [Xen-users] LVM partitions on PV domU

 

Hi All,

 

I am trying to install a 32-bit CentOS 5 paravirtualised domU based on

the instructions at

http://wiki.centos.org/HowTos/Xen/InstallingCentOSDomU.

 

I would like to allocate storage to the domU as a number of LVM

logical volumes instead of a single disk image.

 

Ie.

 

kernel = "/domx/boot/vmlinuz-xen-install"

ramdisk = "/domx/boot/initrd-xen-install"

extra = "text"

 

[...]

 

disk = [ ''phy:/dev/sage/root,xvda1,w'',

        ''phy:/dev/sage/usr,xvda2,w'',

        ''phy:/dev/sage/swap,xvda3,w'',

        ''phy:/dev/sage/tmp,xvda4,w'',

        ''phy:/dev/sage/var,xvda5,w'' ]

[...]

 

I was hoping the logical volumes would appear as partitions inside the

domU, but instead the installer recognises them as separate disk

devices and wants me to partition each of them, ie. xvda11, xvda21,

etc.

 

Is this expected behaviour?

 

Is it at all possible to pass LV partitions through to the domU as

partitions instead of disk devices?

 

dom0 = CentOS 5.2 64-bit

Xen = 3.3.1

 

Thank you.

 

Matthias

 

_______________________________________________

Xen-users mailing list

Xen-users@lists.xensource.com

http://lists.xensource.com/xen-users

 




_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users

Jeff Sturm

2009-Jun-18 05:50 UTC

head link

RE: [Xen-users] LVM partitions on PV domU

The CentOS installers always expect disk images to be whole disks, not
partitions, and to do their own partitioning--i.e. this isn''t really a
Xen question.  You can accomplish the storage layout you''re after, but
not with the native CentOS installers.

The following EC2 page has instructions for installing Fedora to a
single root filesystem, but can easily be adapted to CentOS on multiple
volumes.  The key is preparing for a successful "yum --installroot=...
Groupinstall Base":

http://docs.amazonwebservices.com/AWSEC2/latest/DeveloperGuide/index.htm
l?ami-via-loopback.html

If you want to use multiple volumes instead of one (as in your
root/usr/var example below), create and mount each  (i.e. /mnt,
/mnt/usr, /mnt/var, etc.) before you begin your install.
> -----Original Message-----
> From: xen-users-bounces@lists.xensource.com 
> [mailto:xen-users-bounces@lists.xensource.com] On Behalf Of 
> Matthias Reif
> Sent: Thursday, June 18, 2009 12:38 AM
> To: xen-users@lists.xensource.com
> Subject: [Xen-users] LVM partitions on PV domU
> 
> Hi All,
> 
> I am trying to install a 32-bit CentOS 5 paravirtualised domU 
> based on the instructions at 
> http://wiki.centos.org/HowTos/Xen/InstallingCentOSDomU.
> 
> I would like to allocate storage to the domU as a number of 
> LVM logical volumes instead of a single disk image.
> 
> Ie.
> 
> kernel = "/domx/boot/vmlinuz-xen-install"
> ramdisk = "/domx/boot/initrd-xen-install"
> extra = "text"
> 
> [...]
> 
> disk = [ ''phy:/dev/sage/root,xvda1,w'',
>         ''phy:/dev/sage/usr,xvda2,w'',
>         ''phy:/dev/sage/swap,xvda3,w'',
>         ''phy:/dev/sage/tmp,xvda4,w'',
>         ''phy:/dev/sage/var,xvda5,w'' ]
> [...]
> 
> I was hoping the logical volumes would appear as partitions 
> inside the domU, but instead the installer recognises them as 
> separate disk devices and wants me to partition each of them, 
> ie. xvda11, xvda21, etc.
> 
> Is this expected behaviour?
> 
> Is it at all possible to pass LV partitions through to the 
> domU as partitions instead of disk devices?
> 
> dom0 = CentOS 5.2 64-bit
> Xen = 3.3.1
> 
> Thank you.
> 
> Matthias
> 
> _______________________________________________
> Xen-users mailing list
> Xen-users@lists.xensource.com
> http://lists.xensource.com/xen-users
> 
> 

_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users

Geert Janssens

2009-Sep-23 17:08 UTC

head link

[Xen-users] Manually create Fedora domU on CentOS 5.3 dom0

I am trying to setup a Fedora 11 domU on my CentOS 5.3 dom0 installation.

I want it to use a dom0 LVM partition as its root partition instead of as a 
virtual disk. I understand that Fedora''s anaconda won''t allow
me to do this.

I found this thread on xen-users
http://lists.xensource.com/archives/html/xen-users/2009-06/msg00650.html
Which refers to an Amazon EC2 tech doc, explaining how to install Fedora on a 
single root filesystem.

Following these instructions, I managed to install fedora 11 on an LVM 
partition. However, when attempting to start this setup as a Xen PV, I get 
this error right after pygrub finishes:
Error: (2, ''Invalid kernel'', ''elf_xen_note_check:
ERROR: Will only load images
built for the generic loader or Linux images'')

I''m not sure how to proceed here. Is a special initrd required in a PV 
environment ?

More details:
My environment is all 32 bit (xen, dom0, domU)
dom0 kernel is 2.6.18-128.1.10.el5.centos.plusxen
xen is gitco xen 3.3.1
domU kernel is 2.6.30.5-43.fc11.i586

Geert

-- 
Kobalt W.I.T.
Web & Information Technology
Brusselsesteenweg 152
1850 Grimbergen

Tel  : +32 479 339 655
Email: info@kobaltwit.be


_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users

Geert Janssens

2009-Sep-23 21:36 UTC

head link

Re: [Xen-users] Manually create Fedora domU on CentOS 5.3 dom0

I got a little further.

For the record, the error was due to a kernel mismatch anyway: dom0 was PAE, 
domU not. After having installed the PAE version in domU, I got passed the 
kernel loading.

But not passed boot, I''m afraid.

The domU crashes during the boot sequence. I found this error in the xend.log:
[2009-09-23 23:34:03 4893] DEBUG (DevController:166) Waiting for devices tap.
[2009-09-23 23:34:03 4893] DEBUG (DevController:166) Waiting for devices vtpm.
[2009-09-23 23:34:03 4893] WARNING (XendDomainInfo:1617) Domain has crashed: 
name=Maven id=54.
[2009-09-23 23:34:03 4893] ERROR (XendDomainInfo:1755) VM Maven restarting too 
fast (7.206110 seconds since the last restart).  Refusing to restart to avoid 
loops.
[2009-09-23 23:34:03 4893] DEBUG (XendDomainInfo:2402) XendDomainInfo.destroy: 
domid=54
[2009-09-23 23:34:03 4893] DEBUG (XendDomainInfo:1939) Destroying device model
[2009-09-23 23:34:03 4893] DEBUG (XendDomainInfo:1946) Releasing devices
[2009-09-23 23:34:03 4893] WARNING (image:472) domain Maven: device model 
failure: no longer running; see /var/log/xen/qemu-dm-Maven.log
[2009-09-23 23:34:03 4893] DEBUG (XendDomainInfo:1959) Removing vif/0

This doesn''t say much.

Any idea what''s wrong here, please ?

If more info is needed, just tell me.

Geert

On Wednesday 23 September 2009, Geert Janssens wrote:> I am trying to setup a Fedora 11 domU on my CentOS 5.3 dom0 installation.
>
> I want it to use a dom0 LVM partition as its root partition instead of as a
> virtual disk. I understand that Fedora''s anaconda won''t
allow me to do
> this.
>
> I found this thread on xen-users
> http://lists.xensource.com/archives/html/xen-users/2009-06/msg00650.html
> Which refers to an Amazon EC2 tech doc, explaining how to install Fedora on
> a single root filesystem.
>
> Following these instructions, I managed to install fedora 11 on an LVM
> partition. However, when attempting to start this setup as a Xen PV, I get
> this error right after pygrub finishes:
> Error: (2, ''Invalid kernel'',
''elf_xen_note_check: ERROR: Will only load
> images built for the generic loader or Linux images'')
>
> I''m not sure how to proceed here. Is a special initrd required in
a PV
> environment ?
>
> More details:
> My environment is all 32 bit (xen, dom0, domU)
> dom0 kernel is 2.6.18-128.1.10.el5.centos.plusxen
> xen is gitco xen 3.3.1
> domU kernel is 2.6.30.5-43.fc11.i586
>
> Geert

-- 
Kobalt W.I.T.
Web & Information Technology
Brusselsesteenweg 152
1850 Grimbergen

Tel  : +32 479 339 655
Email: info@kobaltwit.be

_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users

Grant McWilliams

2009-Sep-23 22:07 UTC

head link

Re: [Xen-users] Manually create Fedora domU on CentOS 5.3 dom0

>
> > I found this thread on xen-users
> >
http://lists.xensource.com/archives/html/xen-users/2009-06/msg00650.html
> > Which refers to an Amazon EC2 tech doc, explaining how to install
Fedora
> on
> > a single root filesystem.
> >
> > Following these instructions, I managed to install fedora 11 on an LVM
> > partition. However, when attempting to start this setup as a Xen PV, I
> get
> > this error right after pygrub finishes:
> > Error: (2, ''Invalid kernel'',
''elf_xen_note_check: ERROR: Will only load
> > images built for the generic loader or Linux images'')
> >
> > I''m not sure how to proceed here. Is a special initrd
required in a PV
> > environment ?
> >
> > More details:
> > My environment is all 32 bit (xen, dom0, domU)
> > dom0 kernel is 2.6.18-128.1.10.el5.centos.plusxen
> > xen is gitco xen 3.3.1
> > domU kernel is 2.6.30.5-43.fc11.i586
> >
> > Geert
>
>You know I''m not sure you''re going about this the easiest way.
I''ve never
installed on a LVM partition but I do use them.
I''ll give you the 4 step process that I would have used. Maybe it
doesn''t
match exactly to what you wanted but it''s fast and it works.

1. Download a Fedora Disk Image from Stacklet.
http://stacklet.com/downloads/images/list/Fedora
2. Make your LV.
3. Modify the included domU config file to add the LV as a second disk
4. Start the VM and once booted up, format the LV and use it for whatever
you want.

I''m sure there''s a cleaner way but doing this I can have a
working VM in
about 15 minutes that''s using LVM. For databases it''s worth
the trouble to
use LVM because you gain about 4% in speed on the sql-bench test.

Another thing that is more directly related to your problem is you probably
want to be using the kernel from gitco if you''re using the gitco xen
like
this. This might actually solve your problem as apposed to just avoiding it.
Here''s my grub.conf entry using the gitco xen kernel.

title CentOS (2.6.18-128.4.1.el5xen)
    root (hd0,0)
    kernel /xen.gz-3.4.0
    module /vmlinuz-2.6.18-128.4.1.el5xen ro root=/dev/vgsys/lvroot rhgb
quiet
    module /initrd-2.6.18-128.4.1.el5xen.img


Grant McWilliams


_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users

Xen users - Jun 2009 - LVM partitions on PV domU

[Xen-users] LVM partitions on PV domU

[Xen-users] LVM partitions on PV domU

RE: [Xen-users] LVM partitions on PV domU

RE: [Xen-users] LVM partitions on PV domU

[Xen-users] Manually create Fedora domU on CentOS 5.3 dom0

Re: [Xen-users] Manually create Fedora domU on CentOS 5.3 dom0

Re: [Xen-users] Manually create Fedora domU on CentOS 5.3 dom0