<html><head><meta http-equiv="Content-Type" content="text/html charset=iso-8859-1"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Thanks for the clarification Daniel<div><br><div apple-content-edited="true">
<span class="Apple-style-span" style="color: rgb(0, 0, 0); font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; border-collapse: separate; font-family: 'Lucida Grande'; border-spacing: 0px; -webkit-text-decorations-in-effect: none; "><span class="Apple-style-span" style="font-weight: normal; font-family: Helvetica; "><b style="color: rgb(19, 112, 138); ">Razique Mahroua</b></span><span class="Apple-style-span" style="font-weight: normal; font-family: Helvetica; color: rgb(19, 112, 138); "><b> - </b></span><span class="Apple-style-span" style="font-family: Helvetica; "><span class="Apple-style-span" style="font-weight: normal; font-family: Helvetica; "><b style="color: rgb(19, 112, 138); ">Nuage & Co</b></span><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-style: normal; font-variant: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><span class="Apple-style-span" style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; border-collapse: separate; border-spacing: 0px; -webkit-text-decorations-in-effect: none; "><span class="Apple-style-span" style="border-collapse: separate; font-variant: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; border-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div style="font-weight: normal; color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; "><font class="Apple-style-span" color="#13708a"><a href="mailto:razique.mahroua@gmail.com">razique.mahroua@gmail.com</a></font></div><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; "><font class="Apple-style-span" color="#13708a">Tel : +33 9 72 37 94 15</font></div></span></span></span></span></span><br class="Apple-interchange-newline" style="color: rgb(0, 0, 0); font-family: Arial; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><span><img height="125" width="125" id="8e1aa587-9613-491c-9d12-a9d2e009bc63" apple-width="yes" apple-height="yes" src="cid:0A2450C8-6A0D-42D0-8035-743CAD564432@fabrique.lan"></span>
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<br><div><div>Le 24 avr. 2013 à 17:59, "Daniel P. Berrange" <<a href="mailto:dan@berrange.com">dan@berrange.com</a>> a écrit :</div><br class="Apple-interchange-newline"><blockquote type="cite">On Wed, Apr 24, 2013 at 11:48:35AM -0400, Lorin Hochstein wrote:<br><blockquote type="cite">In the docs, we describe how to configure KVM block-based live migration,<br>and it has the advantage of avoiding the need for shared storage of<br>instances.<br><br>However, there's this email from Daniel Berrangé from back in Aug 2012:<br><a href="http://osdir.com/ml/openstack-cloud-computing/2012-08/msg00293.html">http://osdir.com/ml/openstack-cloud-computing/2012-08/msg00293.html</a><br><br>"Block migration is a part of the KVM that none of the upstream developers<br>really like, is not entirely reliable, and most distros typically do not<br>want to support it due to its poor design (eg not supported in RHEL).<br><br>It is quite likely that it will be removed in favour of an alternative<br>implementation. What that alternative impl will be, and when I will<br>arrive, I can't say right now."<br><br>Based on this info, the OpenStack Ops guide currently recommends against<br>using block-based live migration, but the Compute Admin guide has no<br>warnings about this.<br><br>I wanted to sanity-check against the mailing list to verify that this was<br>still the case. What's the state of block-based live migration with KVM?<br>Should we say be dissuading people from using it, or is it reasonable for<br>people to use it?<br></blockquote><br>What I wrote above about the existing impl is still accurate. The new<br>block migration code is now merged into libvirt and makes use of an<br>NBD server built-in to the QMEU process todo block migration. API<br>wise it should actually work in the same way as the existing deprecated<br>block migration code. So if you have new enough libvirt and new enough<br>KVM, it probably ought to 'just work' with openstack without needing<br>any code changes in nova. I have not actually tested this myself<br>though.<br><br>So we can probably update the docs - but we'd want to checkout just<br>what precise versions of libvirt + qemu are needed, and have someone<br>check that it does in fact work.<br><br>Regards,<br>Daniel<br>-- <br>|: <a href="http://berrange.com">http://berrange.com</a> -o- <a href="http://www.flickr.com/photos/dberrange/">http://www.flickr.com/photos/dberrange/</a> :|<br>|: <a href="http://libvirt.org">http://libvirt.org</a> -o- <a href="http://virt-manager.org">http://virt-manager.org</a> :|<br>|: <a href="http://autobuild.org">http://autobuild.org</a> -o- <a href="http://search.cpan.org/~danberr/">http://search.cpan.org/~danberr/</a> :|<br>|: <a href="http://entangle-photo.org">http://entangle-photo.org</a> -o- <a href="http://live.gnome.org/gtk-vnc">http://live.gnome.org/gtk-vnc</a> :|<br><br>_______________________________________________<br>Mailing list: <a href="https://launchpad.net/~openstack">https://launchpad.net/~openstack</a><br>Post to : <a href="mailto:openstack@lists.launchpad.net">openstack@lists.launchpad.net</a><br>Unsubscribe : <a href="https://launchpad.net/~openstack">https://launchpad.net/~openstack</a><br>More help : <a href="https://help.launchpad.net/ListHelp">https://help.launchpad.net/ListHelp</a><br></blockquote></div><br></div></body></html>