Model-Based Planning for State-Related Changes to Infrastructure and Software as a Service Instances in Large Data Centers

Abstract

Abstract-To deliver 3-tier applications as a Service in the Cloud state-related constraints crossing Infrastructure-and Software as a Service boundaries need to be managed. By automating the lifecycle of applications like databases, load balancers, and web application servers rich SaaS business services can be provided in the Cloud. We propose an object oriented planning approach based on state constraints to plan for changes of SaaS and IaaS components in the Cloud. We evaluate techniques for fast storing and restoring of large object oriented Configuration Management Databases and show that enforcing constraints in a procedural instead of a declarative way offers huge performance improvements. The advantages of our approach lie within the tight integration of the planning algorithm with object oriented models frequently used for Configuration Management Databases. In addition to that, the algorithm scales to a large number of nodes and preserves its runtime even for large, heavily loaded data centers.

Towards solid IT Change Management: Automated detection of conflicting IT change plans

“…This is achieved by restoring previously backed up values of the properties of the affected objects. We found this solution to be the fastest among others in [8]. Line 7 in Alg.…”

“…The advantage of our approach lies within the tight integration of object-oriented (OO) Configuration Management Databases (CMDBs), frequently used by commercial CMDB systems [10] and suggested by the Common Information Model (CIM) [11] to model the current state of software and hardware in a data center. In addition to that, previously proposed work on IT change planning [3], [4], [5], [6], [7], [8] and scheduling [12], [13] remains unchanged while inter-plan conflicts are prevented. The remainder of this work is organized as follows: In Section II we discuss related work and its shortcomings with respect to the occurrence of conflicting IT changes.…”

“…The authors propose an algorithm to refine abstract IT changes without giving logical guarantees about the feasibility of the generated plans. More recent works, such as [4], [5], [7], including our own research [6], [8], propose approaches for IT change planning that reason about the precondition and effects of IT changes within a single plan. For example, the works by Cordeiro et al [5] and Trastour et al [7] focus on the refinement of IT changes, while our hybrid approach [6] addresses refinement and state-based reasoning at the same time.…”

“…In addition to that, object-oriented models have been used in previous research by Eilam et al [23] to describe the state of a data center. IT Change plans are generated by different uncoordinated IT operators or by automated IT change planners [3], [6], [8], [4], [5], [7] based on the current state of the OO CMDB (Step 1). Generated plans are stored in a conflicting plan database (C-plan DB), i.e., a database of unscheduled, but not yet verified to be conflict-free, plans in…”

“…To ensure this, ITIL proposes a Change Management process comprising the evaluation, authorization, planning, test, scheduling, implementation, documentation, and review of IT changes [1]. IT Change Planning, an important step of the Change Management process, has been subject to intensive research [3], [4], [5], [6], [7], [8]. This let to IT change planners which can generate a single sound plan that, when executed, achieves a Request for Change.…”