Resynchronization of objects in a virtual storage system

A non-transitory computer readable medium comprising instructions to be executed in a computing device to cause the computing device to carry out a method of resynchronizing a first replica of an object and a second replica of an object in an object storage system, the object storge system providing storage for a host executing storage software, the method comprising:

• determining, by the storage software in response to the second replica transitioning from failed to available, a stale sequence number for the second replica, the storage software having associated the stale sequence number with the second replica when the second replica failed;
• querying, by the storage software, block-level metadata for the object using the stale sequence number, the block-level metadata relating logical blocks of the object with sequence numbers for operations on the object;
• determining, by the software as a result of the querying, a set of the logical blocks each related to a sequence number being the same or after the stale sequence number;
• and
• copying, by the storage software, data of the set of logical blocks from the first replica to the second replica.

A computer system, comprising:

• a hardware platform comprising an interface to an object storage system, the object storage system storing an object having a first replica and a second replica;
• system software, executing on the hardware platform, including storage software configured to:
• determine, in response to the second replica transitioning from failed to available, a stale sequence number for the second replica, the storage software having associated the stale sequence number with the second replica when the second replica failed;
• query block-level metadata for the object using the stale sequence number, the block-level metadata relating logical blocks of the object with sequence numbers for operations on the object;
• determine, as a result of the querying, a set of the logical blocks each related to a sequence number being the same or after the stale sequence number;
• and
• copy data of the set of logical blocks from the first replica to the second replica.