[linux-lvm] moving a logical volume between servers
basickler at ucdavis.edu
Tue Dec 4 09:03:45 UTC 2007
I'm surprised I couldn't find a good answer to the question before but I
want to move logical volumes from one computer to another.
A little more detail... I created a bunch of xen images on logical
volumes. I brought another computer up to split the load of all the
virtual machines and I want to move some volumes to the new computer.
When I created them I figured I could just dd them like a partition but
upon attempting this and booting the transported xen machine/logical
volume fsck showed some bad errors on the boot partition of the virtual
machine. The later partitions seemed fine.
I did some testing and found that I got the same error no matter the
block size. That if I created a new logical volume on the same machine
as the source and dd'd between them ala
lvcreate -n machine2 -L 20G lvmxen
dd if=/dev/lvmxen/machine of=/dev/lvmxen/machine2
machine2 worked just like machine.
But when I dd'd to a file, moved that file to another computer then dd'd
back into a new logical volume. I had the errors again.
I have some ideas on how to fix the error inside of the virtual machine
but they would be painful considering that I have 10 virtual boxes
running in this configuration.
So, I have a few questions for the lvm guru's.
A. Is it possible to move logical volumes from one computer to another?
And no, these aren't simple ext3 file systems so I can't just mount it
and export the files, they contain entire machines. I was hoping for
something in the nature of lvexport / lvimport but that obviously
B. Why does this occur?... I searched for a while but didn't find
anything concrete as to why this occurs. I've always thought that a
block device = a block device. Evidently I was wrong.
Thanks for any help.
Bioinformatician, Genome Center
University of California, Davis
More information about the linux-lvm