Abstract: Among other things, embodiments described herein enable systems, e.g., Availability Management Forum (AMF) systems, having service units to operate with balanced loads both before and after the failure of one of the service units. A method for balancing standby workload assignments and active workload assignments for a group of service units in a system which employs an N+M redundancy model, wherein N service units are active service units and M service units are standby service units is described. An active workload that the N active service units need to handle is calculated and each of the N active service units in the group is provided with an active workload assignment based on the calculated active workload. Standby workload assignments are distributed among the M standby service units substantially equally.

Abstract: Configuration requirements for an Availability Management Framework (AMF) configuration are generated from high level user requirements that specify a subset of properties of an AMF configuration. The user requirements are first mapped into entity prototypes defined in an extended Entity Types File (ETF) model. A computer system identifies additional entity prototypes and dependency thereof that support functionalities of the mapped entity prototypes under a set of grouping conditions. The computer system calculates the required number of component service instances (CSIs) and service instances (SIs) that satisfy the user requirements. The calculation is based on the subset of the properties specified by the user requirements and measurements associated with the entity prototypes in the extended ETF model. The computer system then forms configuration requirements including the required number of CSIs and SIs for generating the AMF configuration that satisfies the user requirements.

Abstract: A method and system for protecting against failure of hardware elements (HEs) in a virtual machine system using an information model with virtualization support. Based on the information model, the method boots virtual machine monitors (VMMs), virtual machines (VMs) and operating systems (OSes). The information model includes a graph of objects representing configured relationships between the hardware elements (HEs), VMMs, VMs, and OSes through parent child relationships between the graph's objects. The graph of objects includes: a domain object, HE objects, VMM objects, VM objects, and OS objects. The VM objects of a migration-enabled type represent those of the VMs that may migrate between the VMMs. Based on the runtime associations between the VMM objects and the VM objects of the migration-enabled type, the method identifies which of the migration-enabled VMs are hosted by a same HE and are therefore vulnerable to hardware failure of the same HE.

Abstract: Presented are methods and apparatus for protecting a plurality of High Availability (HA) Service Instances (SIs) with a plurality of Service Units (SUs) with an Nway redundancy model. Any of the SUs associated with the Nway redundancy model can simultaneously be assigned an active HA state for some of the SIs and a standby HA state for other SIs. However, only one SU can have the active state for any given SI. The Nway redundancy model is a configured prior to runtime operation.

Abstract: Among other things, embodiments described herein enable systems, e.g., Availability Management Forum (AMF) systems, having service units to operate with balanced loads both before and after the failure of one of the service units. A method for balancing standby workload assignments and active workload assignments for a group of service units in a system which employs an N+M redundancy model, wherein N service units are active service units and M service units are standby service units is described. An active workload that the N active service units need to handle is calculated and each of the N active service units in the group is provided with an active workload assignment based on the calculated active workload. Standby workload assignments are distributed among the M standby service units substantially equally.

Abstract: An Availability Management Framework (AMF) configuration describes how configuration entities of a highly available system are grouped and includes information on service provision and service protection policies against resource failure. The AMF configuration defines a set of failure types for each component and each node, and specifies a failure rate and a recommended recovery for each failure type. A method for evaluating service availability receives the AMF configuration as input, and analyzes it to obtain an actual recovery that the highly available system is to perform when the given component fails. The method maps the AMF configuration to a stochastic model that captures the dependencies among the components and among the configuration entities at multiple levels of the hierarchy. The method utilizes the model to calculate the service availability of the AMF configuration based on the failure rate, the actual recovery and the dependencies.

Abstract: A method and system for protecting against failure of hardware elements (HEs) in a virtual machine system using an information model with virtualization support. Based on the information model, the method boots virtual machine monitors (VMMs), virtual machines (VMs) and operating systems (OSes). The information model includes a graph of objects representing configured relationships between the hardware elements (HEs), VMMs, VMs, and OSes through parent child relationships between the graph's objects. The graph of objects includes: a domain object, HE objects, VMM objects, VM objects, and OS objects. The VM objects of a migration-enabled type represent those of the VMs that may migrate between the VMMs. Based on the runtime associations between the VMM objects and the VM objects of the migration-enabled type, the method identifies which of the migration-enabled VMs are hosted by a same HE and are therefore vulnerable to hardware failure of the same HE.

Abstract: A configuration including Service Instances (SIs) and a list of Service Units (SUs) is to be validated. The SIs are to be allocated to the SUs for protection of the service represented by the SIs. A set of heuristics is applied to determine whether, for each of the SI assignments, the SI can be allocated to one of the SUs whose capacities support the required capacities of the SI. The heuristic then walks the list in order, to find a first SU that supports a current SI. If none of the SUs in the list can support the current SI, the heuristic indicates that the configuration is not validated. In response to a result that at least one of the heuristics in the set indicates the SUs can support all of the SIs, a final result is generated indicating that the configuration is valid.

Abstract: A method and system for generating an Availability Management Framework (AMF) configuration based on a model driven approach. The AMF configuration is an instance of an AMF sub-profile that can be used to model resources and services to be protected, and is generated from an instance of the Entity Type Files (ETF) sub-profile and an instance of the Configuration Requirements (CR) sub-profile. The ETF sub-profile can be used to model the resources provided by vendors, and the CR sub-profile can be used to model configuration requirements. Each of the AMF sub-profile, the ETF sub-profile and the CR sub-profile is a specialization of pre-defined Unified Modeling Language (UML) meta-classes. An input that includes an ETF model and a CR model, which are instances of the ETF sub-profile and the CR sub-profile, respectively, is transformed into an AMF model as the AMF configuration.

Abstract: Methods for providing feedback in messaging systems are described. A communication node can include a first counter for counting a first number of messages which received by and/or forwarded by the node. The communication node can also include a second counter which counts a second number of messages which are expected to be delivered from that node to other nodes.

Abstract: Techniques for generating a system model for use by and availability management framework (AMF) are described. Inputs are received, processed and mapped into outputs which are further processed into a configuration file in an Information Model Management (IMM) Service eXternal Markup Language (XML) format which can be used as a system model by an AMF.

Abstract: Among other things, embodiments described herein enable systems, e.g., Availability Management Forum (AMF) systems, having service units to operate with balanced loads both before and after the failure of one of the service units. A configuration can be generated which provides for distributed backup roles and balanced active loads. When a failure of a service unit occurs, the active loads previously handled by that service unit are substantially evenly picked up as active loads by remaining service units.

Abstract: A node, computer readable medium and method for generating an upgrade campaign for a system. The method includes receiving a current configuration of the system and a set of modifications to be implemented into the system to arrive at a new configuration of the system, automatically selecting an upgrade procedure for each modification in the set of modifications to be either a rolling upgrade procedure or a single step upgrade procedure, or a combination of these and generating the automatically selected upgrade procedure for each modification of the set of modifications.

Abstract: Node, computer software and method for identifying a target set of entities associated with a first configuration of a computer system that are to be modified for arriving at a second configuration of the computer system. The method includes selecting a single service, determining a characteristic of the single service, wherein the characteristic of the service is indicative of whether the single service is provided in both the first and second configurations, only in the first configuration or only in the second configuration, identifying, based on the selected service and its characteristic, one or two corresponding entity groups that are related to the single service, and mapping subsets of entities associated with the identified corresponding entity groups for transitioning the computer system from the first configuration to the second configuration.

Abstract: A distributed model for availability management (AM) functions is described. Core AM functionality is provided by at a global level, while supplemental AM functionality is provided at a local (e.g., cluster) level. Extension entities can be provided to supplement provided AM functions.

Abstract: Techniques for upgrading software associated with layered architectures are described. Based on runtime and/or installation dependencies between the layers, upgrade operations are ordered and performed.

Abstract: Techniques for generating a system model for use by an availability management function (AMF) are described. Inputs are received, processed and mapped into outputs which are further processed into a configuration file in an Information Model Management (IMM) Service external Markup Language (XML) format which can be used as a system model by an AMF.

Abstract: Techniques for generating a system model for use by and availability management framework (AMF) are described. Inputs are received, processed and mapped into outputs which are further processed into a configuration file in an Information Model Management (IMM) Service external Markup Language (XML) format which can be used as a system model by an AMF.

Abstract: A machine, cluster, computer program product and method for choosing an attribute, based on an occurrence of a predetermined event, to be used in a machine of a cluster that includes plural machines. The method includes storing a runtime variable and a configuration variable for each machine of the cluster, selecting, upon the occurrence of the predetermined event, an attribute from a first list of at least one attribute included in the runtime variable in the cluster, accessing, if the runtime variable is not available, the configuration variable, where the configuration variable includes a second list of at least one attribute and selecting an attribute from the second list, and using the selected attribute in the machine.

Abstract: Techniques for dynamic load management in processing systems are described. Tuples or vectors, for example, can be used to characterize loads and capacities. Assignments of tasks and redistribution of tasks in the system can be made using the tuples or vectors.