openstack 虚拟机迁移时应注意的问题

http://blog.youkuaiyun.com/weiyuanke/article/details/8562123

1） hostname 以及hosts文件

（2）libvirt的配置 以及权限

 
 

  
  def 
  
  migrate_disk_and_power_off
  
  (
  
  self
  
  , 
  
  context
  
  , 
  
  instance
  
  , 
  
  dest
  
  ,
 
 
 
 

  
                                     
  
  instance_type
  
  , 
  
  network_info
  
  ,
 
 
 
 

  
                                     
  
  block_device_info
  
  =
  
  None
  
  ):
 
 
 
 

  
          
  
  LOG
  
  .
  
  debug
  
  (
  
  _
  
  (
  
  "Starting migrate_disk_and_power_off"
  
  ),
 
 
 
 

  
                     
  
  instance
  
  =
  
  instance
  
  )
 
 
 
 

  
          
  
  disk_info_text 
  
  = 
  
  self
  
  .
  
  get_instance_disk_info
  
  (
  
  instance
  
  [
  
  'name'
  
  ])
 
 
 
 

  
          
  
  disk_info 
  
  = 
  
  jsonutils
  
  .
  
  loads
  
  (
  
  disk_info_text
  
  )
 
 
 
 


 
 
 
 

  
          
  
  self
  
  .
  
  power_off
  
  (
  
  instance
  
  )
 
 
 
 


 
 
 
 

  
          
  
  block_device_mapping 
  
  = 
  
  driver
  
  .
  
  block_device_info_get_mapping
  
  (
 
 
 
 

  
              
  
  block_device_info
  
  )
 
 
 
 

  
          
  
  for 
  
  vol 
  
  in 
  
  block_device_mapping
  
  :
 
 
 
 

  
              
  
  connection_info 
  
  = 
  
  vol
  
  [
  
  'connection_info'
  
  ]
 
 
 
 

  
              
  
  mount_device 
  
  = 
  
  vol
  
  [
  
  'mount_device'
  
  ]
  
  .
  
  rpartition
  
  (
  
  "/"
  
  )[
  
  2
  
  ]
 
 
 
 

  
              
  
  self
  
  .
  
  volume_driver_method
  
  (
  
  'disconnect_volume'
  
  ,
 
 
 
 

  
                                        
  
  connection_info
  
  ,
 
 
 
 

  
                                        
  
  mount_device
  
  )
 
 
 
 


 
 
 
 

  
          
  
  # copy disks to destination
 
 
 
 

  
          
  
  # rename instance dir to +_resize at first for using
 
 
 
 

  
          
  
  # shared storage for instance dir (eg. NFS).
 
 
 
 

  
          
  
  same_host 
  
  = 
  
  (
  
  dest 
  
  == 
  
  self
  
  .
  
  get_host_ip_addr
  
  ())
 
 
 
 

  
          
  
  inst_base 
  
  = 
  
  libvirt_utils
  
  .
  
  get_instance_path
  
  (
  
  instance
  
  )
 
 
 
 

  
          
  
  inst_base_resize 
  
  = 
  
  inst_base 
  
  + 
  
  "_resize"
 
 
 
 

  
          
  
  try
  
  :
 
 
 
 

  
              
  
  utils
  
  .
  
  execute
  
  (
  
  'mv'
  
  , 
  
  inst_base
  
  , 
  
  inst_base_resize
  
  )
 
 
 
 

  
              
  
  if 
  
  same_host
  
  :
 
 
 
 

  
                  
  
  dest 
  
  = 
  
  None
 
 
 
 

  
                  
  
  utils
  
  .
  
  execute
  
  (
  
  'mkdir'
  
  , 
  
  '-p'
  
  , 
  
  inst_base
  
  )
 
 
 
 

  
              
  
  else
  
  :
 
 
 
 

  
                  
  
  utils.execute('ssh', dest, 'mkdir', '-p', inst_base) //需确保各主机之间可以无密码登陆
 
 
 
 

  
              
  
  for 
  
  info 
  
  in 
  
  disk_info
  
  :
 
 
 
 

  
                  
  
  # assume inst_base == dirname(info['path'])