Metadata synchronization for remote managed systems

A method, comprising:

• performing, by one or more computing devices:
• generating, by a control instance and using a current version of a configuration interface at the control instance, a configuration message for one or more target remote service instances of a plurality of remote service instances, the message including fields according to the current configuration interface version;
• sending the configuration message, according to the current configuration interface version, to a message service for the one or more target remote service instances;
• recording to a data store, the configuration message and configuration interface version sent for the respective ones of the one or more target remote service instances;
• and
• responsive to acknowledgement of the configuration message from one of the target remote service instances:
• marking, for an acknowledgement that is positive or indicates that a version of the configuration interface that is up-to-date, with respect to the version used to generate the message, was used by the target remote service instance to process the configuration message, a record for the configuration message as complete for the target remote service instance;
• or
• marking, for an acknowledgement that is negative or indicates use of an out-of-date configuration interface version, with respect to the version used to generate the message, by the target remote service instance, a record for the configuration message to be re-sent for the target remote service instance.

One or more non-transitory computer-readable media storing program instructions executable on or across one or more processors to implement a managed instance configured to:

• obtain a configuration message from a message service, the configuration message for configuring functionality of the managed instance;
• determine, according to a version of a configuration interface used by the managed instance to process or store the configuration message:
• whether fields of the configuration message are recognized, or
• whether the version of the configuration interface used by the managed instance is out-of-date relative to an interface version indicated for the message;
• where the fields of the configuration message are recognized or the version of the configuration interface is not out-of-date:
• process or store the complete configuration message, and
• send an acknowledgement that is positive or indicates a configuration interface version used by the managed instance that is up-to-date, with respect to the interface version indicated for the configuration message, to a control service;
• and
• where one or more of the fields are unrecognized or the version of the configuration interface is out-of-date:
• process or store the recognized fields, and
• send an acknowledgement that is negative or indicates an out-of-date configuration interface version, with respect to the interface version indicated for the configuration message, to the control service.