Live Migration

0.Testbed Architecture

1.Config Xen

$ sudo vim /etc/xen/xend-config.sxp
(xend-relocation-server yes)
(xend-relocation-address '')
(xend-relocation-hosts-allow '')

2.Command

= xen01 =
$ xm migrate --live vm01 xen01
= xen01=
$ xm list

3.Theory of Live Migration

Reference

• Christopher C., Keir F., Steven H., Jacob G. H., Live migration of virtual machines, 2005

Error message

== xen01 ==
[2008-07-10 11:44:30 xend 6545] ERROR (__init__:1072) Memory reloaded.
[2008-07-10 11:44:30 xend 6545] ERROR (__init__:1072) Decreased reservation by 2088 pages
[2008-07-10 11:44:30 xend 6545] DEBUG (__init__:1072) store-mfn 16246
[2008-07-10 11:44:30 xend 6545] ERROR (__init__:1072) Domain ready to be built.
[2008-07-10 11:44:30 xend 6545] DEBUG (__init__:1072) console-mfn 16245
[2008-07-10 11:44:30 xend 6545] ERROR (__init__:1072) Restore exit with rc=0
[2008-07-10 11:44:32 xend 6545] DEBUG (__init__:1072) Waiting for devices vif.
[2008-07-10 11:44:32 xend 6545] DEBUG (__init__:1072) Waiting for 0.
[2008-07-10 11:44:32 xend 6545] DEBUG (__init__:1072) hotplugStatusCallback /local/domain/0/backend/vif/2/0/hotpl
ug-status.
[2008-07-10 11:44:32 xend 6545] DEBUG (__init__:1072) hotplugStatusCallback 1.
[2008-07-10 11:44:32 xend 6545] DEBUG (__init__:1072) Waiting for devices usb.
[2008-07-10 11:44:32 xend 6545] DEBUG (__init__:1072) Waiting for devices vbd.
[2008-07-10 11:44:32 xend 6545] DEBUG (__init__:1072) Waiting for 2049.
[2008-07-10 11:44:32 xend 6545] DEBUG (__init__:1072) hotplugStatusCallback /local/domain/0/backend/vbd/2/2049/ho
tplug-status.
[2008-07-10 11:44:32 xend 6545] DEBUG (__init__:1072) hotplugStatusCallback 2.
[2008-07-10 11:44:32 xend.XendDomainInfo 6545] DEBUG (__init__:1072) XendDomainInfo.destroy: domid=2
[2008-07-10 11:44:32 xend.XendDomainInfo 6545] DEBUG (__init__:1072) XendDomainInfo.destroyDomain(2)
[2008-07-10 11:44:33 xend 6545] ERROR (__init__:1072) Restore failed
Traceback (most recent call last):
  File "/usr/lib/xen-3.0.3-1/lib/python/xen/xend/XendDomain.py", line 263, in domain_restore_fd
    return XendCheckpoint.restore(self, fd)
  File "/usr/lib/xen-3.0.3-1/lib/python/xen/xend/XendCheckpoint.py", line 165, in restore
    dominfo.waitForDevices() # Wait for backends to set up
  File "/usr/lib/xen-3.0.3-1/lib/python/xen/xend/XendDomainInfo.py", line 1596, in waitForDevices
    self.waitForDevices_(c)
  File "/usr/lib/xen-3.0.3-1/lib/python/xen/xend/XendDomainInfo.py", line 1090, in waitForDevices_
    return self.getDeviceController(deviceClass).waitForDevices()
  File "/usr/lib/xen-3.0.3-1/lib/python/xen/xend/server/DevController.py", line 145, in waitForDevices
    return map(self.waitForDevice, self.deviceIDs())
  File "/usr/lib/xen-3.0.3-1/lib/python/xen/xend/server/DevController.py", line 161, in waitForDevice
    raise VmError("Device %s (%s) could not be connected. "
VmError: Device 2049 (vbd) could not be connected. Backend device not found.