Switching between mediator services for a storage system

A storage system for switching mediators among a plurality of storage systems synchronously replicating data, the storage system comprising a computer processor and a computer memory operatively coupled to the computer processor, the computer memory storing computer program instructions that, when executed by the computer processor, cause the storage system to carry out the steps of:

• determining, among one or more of the plurality of storage systems, a change in availability of a first mediator service, wherein one or more of the plurality of storage systems are configured to request mediation from the first mediator service;
• communicating, among the plurality of storage systems and responsive to determining the change in availability of the first mediator service, a second mediator service to use in response to a fault;
• and
• switching, in dependence upon the change in availability of the first mediator service, from the first mediator service to the second mediator service.

An apparatus for switching mediators among a plurality of storage systems synchronously replicating data, the apparatus comprising a computer processor and a computer memory operatively coupled to the computer processor, the computer memory storing computer program instructions that, when executed by the computer processor, cause the apparatus to carry out the steps of:

• determining, among one or more of the plurality of storage systems, a change in availability of a first mediator service, wherein one or more of the plurality of storage systems are configured to request mediation from the first mediator service;
• communicating, among the plurality of storage systems and responsive to determining the change in availability of the first mediator service, a second mediator service to use in response to a fault;
• and
• switching, in dependence upon the change in availability of the first mediator service, from the first mediator service to the second mediator service.