taking lvm backup

[Tapas Mishra]

On Tue, Sep 28, 2010 at 8:42 PM, Clint Byrum <clint at ubuntu.com> wrote:
>
> If these guests are changing the filesystem, then you will probably
> want to ensure that any databases or such are stopped or locked
> when you back the files up.
I have no idea of what you are saying.


> As somebody else noted, they are probably partitioned, so that is
> probably why you cannot mount them.
How do you notice that.

> The simplest thing would be to just do the backups from inside the
> guest OS's. Is there a reason you don't want to do that?

I could not understand this part.

>>> If it has a filesystem on it, that should detect it, and mount it
>>> readonly, and you should be able to back up only what is *used* on
>>> the volume, not the whole thing. Then just use whatever your favorite
>>> backup method is.
It has a filesystem.

> As someone else stated, its likely that each volume has a partition
> table on it. Given that these are essentially raw disks for guest
> OS's, and not filesystems you created, I don't think its a good
> idea to try and back them up from the host OS.

Then ?
And why is it a bad idea?





2010/9/28 Jorge Armando Medina <jmedina at e-compugraf.com>:

> LVM is not a filesystem, it is just another block device, you need to
> especify the filesistem in the LV.
Ok.
> If you can't mount it with simply mount command, probably it is LV
> partitioned, probably you need to use kpartx with the LV.
>> mount -t lvm2 /dev/nintendo/lvm1 /mnt -o ro
Ok

> For VMs  basically I do something like this:
>
> - Stop the VM
> - Create a snapshot of LV
I could not do this.
I am using Kvm and libvirt clone option is greyed out when I try to do it.
I am accessing the server remotely.Or if this is not the right way then
how to take a snapshot.

> - Start the VM
> - Mount the snapshot
> - backup the data on the snapshot
>
> For informataion about VM management read the documentation of the
> product you are using, for more info about LVM read the official howto,
Can you give a link to official how to or what ever you are referring?






On Tue, Sep 28, 2010 at 9:24 PM, Matt Darcy
<ubuntu.lists at projecthugo.co.uk> wrote:
>
> lvm isn't a file system - you should know what file system you put on
> them, ext3, ext4, xfs etc.
Ok I shall try this and get back here.
-- 
Tapas