About: Back up LVM xen guest containing lvs

[karateckie]

http://www.howtoforge.com/back-up-lv...containing-lvs

Hello!
I have a question regarding the last part of the How To where it warns to make sure and unmount the volume, then delete the device map created by kpartx.

In my case I do not have a xen guest containing LVs, but I have a Windows Xen guest with an NTFS formatted volume. I am able to create the device with kpartx and mount the partition using ntfs-3g. So there's no problem there.

My question is, can the file system become corrupt if I am only mounting the partition of the Xen Guest as read only?? I'd like to leave the filesystem mounted for periodic backups from the Centos 5.4 host. Is that a bad idea? If so, can someone point me to a "why this is a bad idea" type of document/page? Thanks a bunch! I'm trying to determine if there are cases where the file system becomes corrupt that don't apply to my setup since I don't have LVs inside of a guest.

Kara

[karateckie]

Can anyone explain where the corruption happens with leaving kpartx maps in place? My primary question: is corruption possible even if the partion inside the guest LV is mounted read only on the host?

The LV in question is only used for data storage. So it is possible that the guest could be performing a write operation on the data when the host is trying to read. Is this a problem?

Thanks,
Kara