Abstract: Various examples are directed to systems and methods for operating a database management system. A first host of a first version may be executed at a first container of a cloud environment. A second host of a second version may be executed at a second container of the cloud environment. The first host may be configured to perform a source role and the second host may be configured to perform a replica role corresponding to the source role. A network layer executing at the cloud environment may receive a request directed to the second host. The network layer may determine that the request is consistent with allowed request data describing allowed requests and may send the request to the second host.

Abstract: A scale-out computing cluster may include a large number of computing servers and storage devices. In order to provide high reliability, the computing cluster must be able to handle failures of individual devices. Reliability of the computing cluster may be improved by providing a standby server for each active server in the computing cluster. If any active server fails, the corresponding standby server is activated. The failed server may be brought back online or replaced, at which time the restored server becomes the standby server for the now-active original standby server. During the restoration period, if any other active server fails, the standby server for that active server is immediately activated. As a result, the recovery ability of the computing cluster is only challenged if both servers of an active/standby pair fail during the restoration period, substantially improving reliability.

Abstract: A scale-out computing cluster may include a large number of computing servers and storage devices. In order to provide high reliability, the computing cluster must be able to handle failures of individual devices. Reliability of the computing cluster may be improved by providing a standby server for each active server in the computing cluster. If any active server fails, the corresponding standby server is activated. The failed server may be brought back online or replaced, at which time the restored server becomes the standby server for the now-active original standby server. During the restoration period, if any other active server fails, the standby server for that active server is immediately activated. As a result, the recovery ability of the computing cluster is only challenged if both servers of an active/standby pair fail during the restoration period, substantially improving reliability.

Abstract: Various examples described herein are directed to systems and methods for operating a database management system. A first host may be executed at a first container of a cloud environment. The first host may be configured according to a first set of operating parameters and may perform a source role. A second host may be executed at a second container of the cloud environment. The second host may be configured according to the first set of operating parameters and may perform a replica role or the source role. A request to modify at least one operating parameter of the first source may be received. A third host may be started at a third container and configured to perform at least one of the source role or the replica role for the source role. At least one of the first host or the second host may be shut down.

Abstract: Various examples are directed to systems and methods for operating a database management system. A first host of a first version may be executed at a first container of a cloud environment. A second host of a second version may be executed at a second container of the cloud environment. The first host may be configured to perform a source role and the second host may be configured to perform a replica role corresponding to the source role. A network layer executing at the cloud environment may receive a request directed to the second host. The network layer may determine that the request is consistent with allowed request data describing allowed requests and may send the request to the second host.

Abstract: A scale-out computing cluster may include a large number of computing servers and storage devices. In order to provide high reliability, the computing cluster must be able to handle failures of individual devices. Reliability of the computing cluster may be improved by providing a standby server for each active server in the computing cluster. If any active server fails, the corresponding standby server is activated. The failed server may be brought back online or replaced, at which time the restored server becomes the standby server for the now-active original standby server. During the restoration period, if any other active server fails, the standby server for that active server is immediately activated. As a result, the recovery ability of the computing cluster is only challenged if both servers of an active/standby pair fail during the restoration period, substantially improving reliability.