Automatic failover during online data migration

摘要

A technique automatically handles a failure during online data migration from a source array to a target array. While a host initially accesses data from the source array using multipath I/O software, the technique involves (i) transitioning the source array to a passive mode, and the target array to an active mode, and (ii) beginning a data transfer operation which transfers data from the source array to the target array. The technique further involves modifying the data on both the target array and the source array in response to modification commands sent to the target array from the host while the data transfer operation is ongoing. The technique further involves automatically failing back to providing access to the data from the source array in response to an event in which the target array loses communication with the source array for a predefined amount of time.

主权项

1. A method of migrating data from a source array to a target array, the method comprising:
configuring (i) the target array to perform host input/output (I/O) operations in place of the source array and (ii) the source and target arrays to perform a failover procedure in response to a timeout event, the failover procedure involving performance of further host I/O operations by the source array in place of the target array upon occurrence of the timeout event; initiating a data migration process in which data is copied from the source array to the target array; and while the data is copied from the source array to the target array during the data migration process, exchanging heartbeat signals between the source array and the target array to prevent occurrence of the timeout event.