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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>+1<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>It is certainly worth a session to decide how to modify the scheduler.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I suspect all you would need is to do on the compute side is add a stub implementations for add/remove host operations in the compute manager base class (rather than throw NotImplemented exceptions), and maybe an extra XenServer specific flag to suppress the pool creation. I think it has all the DB and metadata functionality required.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>One thing worth raising, is that currently all hosts in an aggregate must be in the same availability zone. That seems reasonable to me.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Vishvananda Ishaya [mailto:vishvananda@gmail.com] <br><b>Sent:</b> 03 April 2012 19:11<br><b>To:</b> Day, Phil<br><b>Cc:</b> John Garbutt; Jan Drake; Lorin Hochstein; openstack@lists.launchpad.net<br><b>Subject:</b> Re: [Openstack] Limit flavors to specific hosts<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Apr 3, 2012, at 6:45 AM, Day, Phil wrote:<o:p></o:p></p></div><p class=MsoNormal><br><br><o:p></o:p></p><div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hi John,</span><span lang=EN-GB><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><span lang=EN-GB><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Maybe the problem with host aggregates is that it too quickly became something that was linked to hypervisor capability, rather than being the more general mechanism of which one form of aggregate could be linked to hypervisor capabilities ?</span><span lang=EN-GB><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><span lang=EN-GB><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-GB style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Should we have a “host aggregates 2.0” session at the Design Summit ?</span><span lang=EN-GB><o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>+ 1<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I think the primary use case is associating metadata with groups of hosts that can be interpreted by the scheduler. Obviously, this same metadata can be used to create pools/etc. in the hypervisor, but we can't forget about the scheduler. Modifying flags on the hosts for capabilities is ugly.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Vish<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p></div></div></body></html>