<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: Times New Roman; font-size: 12pt; color: #000000'>Eric,<div><br></div><div>Thanks for the clarification. I will wait for a backport of qemu 1.1 for Ubuntu 12.04 so I can use the safer 'transaction' monitor command for performing live snapshots/backups. Is there any other recommended method for live backups?</div><div><br></div><div>Andrew<br><br><hr id="zwchr"><div style="color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;"><b>From: </b>"Eric Blake" <eblake@redhat.com><br><b>To: </b>"Andrew Martin" <amartin@xes-inc.com><br><b>Cc: </b>libvirt-users@redhat.com<br><b>Sent: </b>Friday, August 17, 2012 9:43:23 AM<br><b>Subject: </b>Re: [libvirt-users] Live Snapshot and Rebasing using blockpull<br><br>On 08/17/2012 08:27 AM, Andrew Martin wrote:<br>> <br>> 1. virsh snapshot-create-as to create the snapshot <br>> 2. cp myvm.qcow2 myvm-backup.qcow2 to copy off the now read-only backing image file <br>> 3. virsh blockpull to merge the base and snapshot images together into a single image again <br><br>Yep. As long as you don't mind the single image changing names, this<br>works (and if you _do_ mind it changing names, you can do the process<br>twice to get back to the original name, although that's obviously not<br>very efficient).<br><br>There are future improvements coming down the pipeline for even more<br>efficient block manipulations, but they missed the qemu 1.2 cutoff, so<br>now I have to wait for qemu 1.3 (probably closer to December of this<br>year) before having libvirt control over those features - but I am<br>actively working on this area of code.<br><br>> <br>> <br>> Is this functionality only available in qemu 1.1?<br><br>snapshot-create-as was introduced in libvirt 0.9.5, and requires the<br>qemu 'blockdev-snapshot-sync' monitor command (since 0.14.0), but<br>prefers the 'transaction' monitor command (since 1.1) for safety.<br><br>blockpull was introduced in libvirt 0.9.4, and requires the qemu<br>'block-stream' monitor command (since 1.1).<br><br>> I am using Ubuntu 12.04 LTS on production servers which only includes qemu 1.0.x. Is there a safe alternative for accomplishing live backups like this on qemu 1.0.x? Is there a minimum version of libvirt that supports this behavior? <br><br>It sounds like you can take snapshots but not merge them back while your<br>domain is online, because your qemu is too old. But you can use<br>'qemu-img' to do offline merging, if having your domain offline is not<br>an issue.<br><br>-- <br>Eric Blake eblake@redhat.com +1-919-301-3266<br>Libvirt virtualization library http://libvirt.org<br><br></div><br></div></div></body></html>