Managed orchestration of virtual machine instance migration

Abstract

A migration of a virtual machine running on a source host is determined to be performed for the virtual from the source host to a target host. The virtual machine is migrated from the source host to the target host at least by copying a state of the virtual machine from the source host to the target host while the virtual machine is running on the source host. Packets are caused to be forwarded to the virtual machine running on the target host.

What is claimed is: 
     
         1 . A computer-implemented method, comprising:
 determining, for a virtual machine running on a source host, to perform a migration of the virtual machine from the source host to a target host;   migrating the virtual machine from the source host to the target host at least by copying a state of the virtual machine from the source host to the target host while the virtual machine is running on the source host; and   causing packets to be forwarded to the virtual machine running on the target host.   
     
     
         2 . The computer-implemented method of  claim 1 , wherein causing the packets to be forwarded includes configuring the virtual machine running on the source host to:
 receive a data packet from a service; and   forward the data packet to the virtual machine running on the target host.   
     
     
         3 . The computer-implemented method of  claim 1 , wherein causing the packets to be forwarded includes configuring the virtual machine running on the source host to retain a connection with an external resource during migration. 
     
     
         4 . The computer-implemented method of  claim 1 , further comprising attaching a network resource to the virtual machine running on the target host. 
     
     
         5 . The computer-implemented method of  claim 1 , further comprising:
 tracking a change made to the state of the virtual machine running on the source host during migration; and   propagating the change to the virtual machine running on the target host.   
     
     
         6 . The computer-implemented method of  claim 5 , wherein propagating the change to the virtual machine running on the target host occurs during the migration. 
     
     
         7 . The computer-implemented method of  claim 5 , wherein propagating the change to the virtual machine running on the target host occurs after the migration is completed. 
     
     
         8 . A system, comprising:
 one or more processors; and   memory including executable instructions that, if executed by the one or more processors, cause the system to:
 determine, for a virtual machine running on a source host, to perform a migration of the virtual machine from the source host to a target host; 
 as a result of determining to perform the migration, copy a state of the virtual machine from the source host to the target host while the virtual machine is running on the source host; and 
 cause packets to be forwarded to the virtual machine running on the target host. 
   
     
     
         9 . The system of  claim 8 , wherein the executable instructions further cause the system to:
 upon completion of the migration, terminate the virtual machine running on the source host; and   reclaim a resource allocated to the virtual machine running on the source host.   
     
     
         10 . The system of  claim 8 , wherein the executable instructions further cause the system to configure the virtual machine running on the source host to:
 submit a request to a block storage device;   receive, at the virtual machine running on the source host from the block storage device, a response to the request; and   forward the response to the virtual machine running on the target host.   
     
     
         11 . The system of  claim 8 , wherein the executable instructions further cause the system to determine to perform the migration as a result of a change in availability of a resource associated with the source host. 
     
     
         12 . The system of  claim 8 , wherein the executable instructions further cause the system to:
 configure the virtual machine running on the source host to retain a connection with an external resource; and   forward any packets received from the external resource to the virtual machine running on the target host.   
     
     
         13 . The system of  claim 8 , wherein the executable instructions configure the virtual machine running on the source host to forward the packets to the virtual machine running on the target host. 
     
     
         14 . The system of  claim 13 , wherein the executable instructions that cause the system to configure the virtual machine further include instructions that configure the virtual machine running on the source host to:
 receive a data packet from a service; and   forward the data packet to the virtual machine running on the target host.   
     
     
         15 . A non-transitory computer-readable storage medium storing thereon executable instructions that, if executed by one or more processors of a computer system, cause the computer system to at least:
 determine, for a virtual machine running on a source host, to perform a migration of the virtual machine from the source host to a target host;   migrate the virtual machine from the source host to the target host at least by causing the computer system to copy a state of the virtual machine from the source host to the target host while the virtual machine is running on the source host; and   cause packets to be forwarded to the virtual machine running on the target host.   
     
     
         16 . The non-transitory computer-readable storage medium of  claim 15 , wherein the executable instructions further cause the computer system to configure the virtual machine running on the source host to:
 retain a connection with an external resource;   receive a data packet received from the external resource; and   forward the data packet to the virtual machine running on the target host.   
     
     
         17 . The non-transitory computer-readable storage medium of  claim 15 , wherein the executable instructions that cause the computer system to cause packets to be forwarded to the virtual machine running on the target host further configure the virtual machine running on the source host to:
 receive a response to a request made to a service of a service provider; and   forward the response to the virtual machine running on the target host.   
     
     
         18 . The non-transitory computer-readable storage medium of  claim 17 , wherein:
 the service is a block storage service that provides a block storage device; and   the executable instructions further cause the computer system to configure the virtual machine running on the source host to:
 submit the request to the block storage device; and 
 receive the response from the block storage device. 
   
     
     
         19 . The non-transitory computer-readable storage medium of  claim 15 , wherein the executable instructions further cause the computer system, during copying of the state of the virtual machine, to:
 track a change made to the virtual machine while the virtual machine is running on the source host; and   propagate the change to the virtual machine running on the target host.   
     
     
         20 . The non-transitory computer-readable storage medium of  claim 19 , wherein the change occurs as a result of fulfilment of a request received at the virtual machine running on the source host during the copying.