Re: [Xen-users] how to create guest image file ?

[Jeremy Fang <balanceinfotech@xxxxxxxxx>]

Hi Andrew:

 

Currently I have guest OS running on /dev/sda7 with RedHat 8.0 and I would like to create

an image file from it so that I can boot from the file instead of physical disk partition.

 

Do you have any luck doing that ?

 

Here is what I tried:

 

1. on xen machine

    mount /dev/sda2   /temp       // /dev/sda2 have enough space

    dd if=/dev/sda7   of=/temp/sda7.imge bs=64k

 

 2. cd /etc/xen/auto   create a configure file as show following:

 

# Kernel image file.
kernel = "/boot/vmlinuz-2.4-xenU"

# Optional ramdisk.
#ramdisk = "/boot/initrd.gz"

# The domain build function. Default is 'linux'.
#builder='linux'

# Initial memory allocation (in megabytes) for the new domain.
memory = 128

# A name for your domain. All domains must have different names.
name = "sda2_image"

# Which CPU to start domain on?
#cpu = -1   # leave to Xen to pick

#----------------------------------------------------------------------------
# Define network interfaces.

# Number of network interfaces. Default is 1.
#nics=1

# Optionally define mac and/or bridge for the network interfaces.
# Random MACs are assigned if not given.
#vif = [ 'mac=aa:00:00:00:00:11, bridge=xen-br0' ]

#----------------------------------------------------------------------------
# Define the disk devices you want the domain to have access to, and
# what you want them accessible as.
# Each disk entry is of the form phy:UNAME,DEV,MODE
# where UNAME is the device, DEV is the device name the domain will see,
# and MODE is r for read-only, w for read-write.

 

disk = ['file:/root/sda2.img,sda2,w']

#----------------------------------------------------------------------------
# Set the kernel command line for the new domain.
# You only need to define the IP parameters and hostname if the domain's
# IP config doesn't, e.g. in ifcfg-eth0 or via DHCP.
# You can use 'extra' to set the runlevel and custom environment
# variables used by custom rc scripts (e.g. VMID=, usr= ).

# Set if you want dhcp to allocate the IP address.
#dhcp="dhcp"
# Set netmask.
#netmask=
# Set default gateway.
#gateway=
# Set the hostname.
#hostname= "vm%d" % vmid

# Set root device.
root = "/dev/sda2 rw"

# Root device for nfs.
#root = "/dev/nfs"
# The nfs server.
#nfs_server = '169.254.1.0' 
# Root directory on the nfs server.
#nfs_root   = '/full/path/to/root/directory'

# Sets runlevel 4.
extra = "4"

#----------------------------------------------------------------------------
# Set according to whether you want the domain restarted when it exits.
# The default is 'onreboot', which restarts the domain when it shuts down
# with exit code reboot.
# Other values are 'always', and 'never'.

#restart = 'onreboot'

 

3. xm create sda2.img -c

 

Here is what I get the error message:

 

[root@xen auto]# xm create sda2_img -c
Using config file "sda2_image".
Error: Error creating domain: vbd: Segment not found: uname=file:/root/sda2.img

 

Any clues ?

 

Thanks,

 

Jeremy

 

P.S. by the way, I tried other way to create imge file for RedHat 8.0 with no luck with the

       following url links:

                

http://www.fedoralegacy.org/docs/yum-rh8.php

http://www.fedoraproject.org/wiki/FedoraXenQuickstart

 

Andrew Thompson <andrewkt@xxxxxxxxxxx> wrote:

> Jeremy Fang wrote:
> > Hello All:
> > 
> > Currently I have xen system running RedHat enterprise version 3 and two 
> > Guest OS running on top of that in which one is run as RedHat 8.0 and 
> > the other is RedHat 7.2. All the applicaton software running on the two 
> > Guest OS are functioning well. My goal is find a way to migrate these 
> > two guest OS + its application to other two physical servers without xen 
> > running on that.
> > I don't need to do Live Migration.
> > 
> > Therefore, the questions are:
> > 
> > 1) Is it feasible to do that ?
> > 2) If it is feasible, how to do it and what tools do I need to achieve 
> > that ?
>
> It sounds like a simple copy of your partition to the new machine. (Or, 
> did I miss something?)
>
> First, you should probably build kernels on the guests that can
>  
> successfully boot the new servers(or have a verified boot cd handy).
>
> If you can temporarily pull the drive, it might take less time to walk 
> the drive to the new machine and cp -a or tar | tar to the harddrive in 
> the new machine.
>
> Basically you just need to transfer the filesystem(with permissions, 
> links, etc) to the new server, tweak your /etc/fstab, and lilo/grub your 
> kernel into place.
>
> If they are large partitions, there is a tool on the samba website that 
> supposedly compresses better than gzip or bzip2, but it's name now 
> eludes me.
>
> -- 
> Andrew Thompson
> http://aktzero.com/
> begin:vcard
> fn:Andrew Thompson
> n:Thompson;Andrew
> email;internet:andrewkt@xxxxxxxxxxx
> x-mozilla-html:FALSE
> url:http://aktzero.com/
> version:2.1
> end:vcard
>
> _______________________________________________
> Xen-users mailing list
> Xen-users@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-users

---

 Start your day with Yahoo! - make it your home page
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users