Zero-data loss recovery for active-active sites configurations

A computer program product for providing continuous availability, the computer program product comprising:

• a computer readable storage medium having stored thereon:
• first program instructions executable by a processor to cause a first group of workloads of a first computing site to:
• receive units of work data, process the units of work data, and output data results in response to the processing of the units of work data, wherein the first group of workloads includes a database;
• second program instructions executable by a processor to cause a first software replication module of the first computing site to asynchronously replicate the units of work data to a second computing site, the second computing site being geographically remote from the first computing site, wherein the units of work data that are asynchronously replicated includes a subset of logged transactional data, wherein the first software replication module employs a log capture replication technique that filters logged transactional data and provides access to active log buffers via one or more database management system (DBMS) interfaces of the first computing site, wherein the active log buffers store log records at least before the log records are persisted to a disk on a DBMS commit, wherein the log capture replication technique filters out log records by sending to the second computing site only change column values for transactions that update the database;
• third program instructions executable by a processor to cause a first storage unit of the first computing site to store the units of work data and the outputted data results;
• fourth program instructions executable by a processor to cause a hardware replication module of the first computing site to synchronously replicate, from the first storage unit to the second computing site, the units of work data and the outputted data results, wherein the units of work data and the outputted data results that are synchronously replicated by the hardware replication module are associated with disk write operations and not with disk read operations;
• fifth program instructions executable by a processor to cause a second storage unit of the second computing site to store the units of work data that were synchronously replicated from the first computing site to the second computing site and to store the outputted data results that were synchronously replicated from the first computing site to the second computing site;
• sixth program instructions executable by a processor to cause a second group of workloads of the second computing site to process the units of work data that were asynchronously replicated from the first computing site;
• and
• seventh program instructions executable by a processor to cause:
• a read-only computing component of the second computing site to activate in response to detecting an outage of the first computing site;
• and
• a second software replication module of the second computing site to start asynchronous replication of the units of work data stored in the second storage unit to the second group of workloads in response to the detected outage of the first computing site such that asynchronous replication is resumed for any units of the units of work data that have not been asynchronously replicated to the second group of workloads due to the detected outage of the first computing site.