VIRTUAL MACHINE INSTANCE MIGRATION USING A TRIANGLE APPROACH

摘要

Techniques for preserving the state of virtual machine instances during a migration from a source location to a target location are described herein. A set of credentials configured to provide access to a storage device by a virtual machine instance at the source location is provided to the virtual machine instance. When the migration from the source location to the target location starts, a second set of credentials configured to provide access to a storage device by a virtual machine instance at the source location is provided to the virtual machine instance. During the migration, a response to an input-output request is provided to one or more of the locations using the set of credentials and based at least in part on the state of the migration.

主权项

1. A computer-implemented method, comprising:
under the control of a block-level storage service computer system configured with executable instructions,
obtaining a first lease associating a virtual machine instance with a block storage device, the block storage device provided by the block-level storage service, the first lease specifying a first policy of access to the block storage device by the virtual machine instance, the first lease having a first status of active;receiving an indicator of a start of a migration of the virtual machine instance from a source computing device to a target computing device;generating a second lease associating the virtual machine instance in the target computing device with the block storage device, the second lease specifying a second policy of access to the block storage device by the virtual machine instance, the second lease having a second status of standby;updating the first status and the second status based at least in part on an indicator of progress of the migration;receiving a set of input-output requests addressing the block storage device from the virtual machine instance; andproviding a response to input-output requests of the set of input-output requests, the response at least specifying a response location to which to send the response, the response location determined based at least in part on whether the first status is active, the response location selected from the source computing device and the target computing device.