Live Migration

Author: Rock Kuo

0.Testbed Architecture

• config DRBL client

  * rm /tftpboot/boot
  $ mkdir /tftpboot/boot
  $ cp /boot/*xen* /tftpboot/node_root/boot
  

• Xen in DRBL

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 create vm01.cfg
$ xm migrate --live vm01 xen03
$ xm list
Name                                      ID Mem(MiB) VCPUs State   Time(s)
Domain-0                                   0     1477     4 r-----    226.9

= xen03 =
$ xm list
Name                                      ID Mem(MiB) VCPUs State   Time(s)
Domain-0                                   0     1477     4 r-----    530.9
vm01                                       2      512     1 -b----      0.0

• When we migrate vm01, we still ping vm06. You can see icmp_seq 37~52, the ethX of vm01 will don't networking until vm01 migrate success.

3.Theory of Live Migration

4.Reference

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

5.Problem

• xen01
  • VmError: Device 2049 (vbd) could not be connected. Backend device not found.

    check loop module
    

• vm01 in xen01
  • netfront: device eth0 has flipping receive path
• vm01 in xen01 can't networking
  • Xen maybe use xen01 eth0 configuration, but drbl client interface is work in initrd step. (/etc/network/interface in xen01 has nothing )
  • It maybe xen don't bridge to eth0 of xen01.
• If you use two NIC in DRBl client
  • you must edit route table, then startup xen (it will bridge to second ethX)