Hi all, On Xen v3.0 Users'' Manual it has the part "8.2 Migration and Live Migration".But if the primary physical machine suddenly crashed,we will not be able to do live migration.Is it right?I mean,can Xen have the same function as Vmware esx server''s vmotion(when the primary physical machine crashed,the virtual hosts on it can be automatically migrated to the second Vmware esx server)? Thanks for your advice and suggestion. -------------- Yours, XUFENG 2009-03-31 _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
"XUFENG" <xufengnju@sina.com> writes:> On Xen v3.0 Users'' Manual it has the part "8.2 Migration and Live Migration". > But if the primary physical machine suddenly crashed,we will not be able to do > live migration.Is it right?Yes.> I mean,can Xen have the same function as Vmware esx server''s vmotionI believe vmotion does almost exactly what live migration does, that is, move from one running, healthy hoast to another. It is ... difficult to copy bits out of ram when the server is dead.> (when the primary physical machine crashed,the virtual hosts on it can be > automatically migrated to the second Vmware esx server)?I forget what VMWARE calles this, but I''m pretty sure it''s not vmotion. Also, for this to work in vmware, you need the second server up and running in ''hot standby'' mode. From what I understand, the memory state of the second image is kept approximately the same as the first image; this is how it avoids the problem of copying bits out of ram on the dead server. In some cases, it''s quite useful; but it''s not free. you are using two servers to get the work of one server. similar features, I believe, are planned for the Xen 3.4 release. As of now, though, with the default hypervisor, there is no such functionality in xen. check out http://www.usenix.org/events/nsdi/tech/full_papers/cully/cully_html/index.html for some info. -- Luke S. Crawford http://prgmr.com/xen/ - Hosting for the technically adept We don''t assume you are stupid. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Thiago Camargo Martins Cordeiro <thiagocmartinsc@gmail.com> writes:> Project Kemari does VM live motion when one node dies automagically... > > http://www.osrg.net/kemariYeah. but again it synchronizes to a backup node (and again you need a special/patched hypervisor if you are running 3.3.) the idea is that the ram state of the vm on the active node and the backup node are kept synchronized, so when the active node dies, you can activate the backup node. My point is that this is different from ''live migration'' because you are using twice the resources. You are running the live and the backup nodes in parallel. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
2009/3/31 XUFENG <xufengnju@sina.com>:> On Xen v3.0 Users'' Manual it has the part "8.2 Migration and Live Migration".But if the primary physical machine suddenly crashed,we will not be able to do live migration.Is it right?I mean,can Xen have the same function as Vmware esx server''s vmotion(when the primary physical machine crashed,the virtual hosts on it can be automatically migrated to the second Vmware esx server)?Within ESX this function is called HA (High Availability) rather than vMotion. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Tue, Apr 14, 2009 at 11:44 AM, Andy Burns <xen.lists@burns.me.uk> wrote:> 2009/3/31 XUFENG <xufengnju@sina.com>: > >> On Xen v3.0 Users'' Manual it has the part "8.2 Migration and Live Migration".But if the primary physical machine suddenly crashed,we will not be able to do live migration.Is it right?I mean,can Xen have the same function as Vmware esx server''s vmotion(when the primary physical machine crashed,the virtual hosts on it can be automatically migrated to the second Vmware esx server)? > > Within ESX this function is called HA (High Availability) rather than vMotion.does it really work? how is it done? are the VMs restarted on the second host? or rolled back to a snapshot taken (automatically? what frequency?) before the crash? -- Javier _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Tue, 2009-04-14 at 11:51 -0500, Javier Guerra wrote:> > does it really work? how is it done? are the VMs restarted on the > second host? or rolled back to a snapshot taken (automatically? what > frequency?) before the crash?ESX HA is just an "oh, that machine died, boot its vm''s over here" sort of feature. You could (very?) easily duplicate this functionality with heartbeat. John -- John Madden Sr UNIX Systems Engineer Ivy Tech Community College of Indiana jmadden@ivytech.edu _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Tue, Apr 14, 2009 at 12:14 PM, John Madden <jmadden@ivytech.edu> wrote:> On Tue, 2009-04-14 at 11:51 -0500, Javier Guerra wrote: >> >> does it really work? how is it done? are the VMs restarted on the >> second host? or rolled back to a snapshot taken (automatically? what >> frequency?) before the crash? > > ESX HA is just an "oh, that machine died, boot its vm''s over here" sort > of feature. You could (very?) easily duplicate this functionality with > heartbeat.ah, ok. no dark magic there. -- Javier _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users