Configuration management database
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A configuration management database (CMDB) is a repository that acts as a data warehouse for information technology (IT) organizations. Its contents are intended to hold a collection of IT assets that are commonly referred to as Configuration Items (CIs), as well as descriptive relationships between such assets. When populated, the repository becomes a means of understanding how critical assets such as information systems are composed, what their upstream sources or dependencies are, and what their downstream targets are.
CMDBs are used to keep track of the state of different things that are normally referred to as assets, such as products, systems, software, facilities, and people as they exist at specific points in time. The maintenance of such state related information allows for things like the reconstruction of such assets, at any point in their existence, as well as for things such as impact analysis, in the cases of root cause analysis or change management.
The Information Technology Infrastructure Library framework, also known as ITIL describes the use of CMDBs as part of infrastructure operations and support. In the ITIL context, a CMDB represents the authorized configuration of the significant components of the IT environment.
A CMDB helps an organization understand the relationships between the components of a system and track their configurations. The CMDB is a fundamental component of the ITIL framework's Configuration Management process. CMDB implementations often involve federation, the inclusion of data into the CMDB from other sources, such as Asset Management, in such a way that the source of the data retains control of the data. Federation is usually distinguished from ETL (extract, transform, load) solutions in which data is copied into the CMDB.
The CMDB records configuration items (CI) and details about the important attributes and relationships between CIs. Configuration managers usually describe CIs using three configurable attributes:
A key success factor in implementing a CMDB is the ability to automatically discover information about the CIs (auto-discovery) and track changes as they happen.
CMDBs contain metadata, and thus the concept overlaps with that of a metadata repository which are both used in running large IT organizations. Configuration management addresses how the data is to be kept up to date, which has historically been a weakness of metadata repositories.
CMDB schematic representations
Relational data models are based on first-order predicate logic and all data is represented in terms of tuples that are grouped into relations. In the relational model, related records are linked together with a "key", where the key is unique to an entry's data type definition. Such relational models provide declarative methods for specifying data and queries. In other words, users directly state what information the database contains and what information they want from it, and let the database system take care of describing data structures for storing the data and retrieval procedures for answering queries.
Semantic data models typically rely on the resource description framework and use a model that simply relates any thing to any other thing through the use of a relationship descriptor, giving context to how things are related to each other.
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- "Configuration Management Database Definition". The International Foundation for Information Technology. September 2010.
- H. Madduri, S.S.B. Shi, R. Baker, N. Ayachitula (6 April 2010). A configuration management database architecture in support of IBM Service Management. Institute of Electrical and Electronics Engineers, The (IEEE). doi:10.1147/sj.463.0441.