Configuration Management Database (CMDB)

Configuration Management Database (CMDB) is a centralized repository that stores information on all the significant entities in your IT environment. The entities, termed as Configuration Items (CIs) can be hardware, the installed software applications, documents, business services and also the people that are part of your IT system. Unlike the asset database that comprises of a bunch of assets, the CMDB is designed to support a vast IT structure where the interrelations between the CIs are maintained and supported successfully.

A CMDB contains the configuration items (CI) or information system components within an enterprise IT infrastructure. It helps identify the different components of an information system and their configuration and stores this data in the form of metadata. The CI stored by a CMDB can be any IT component from hardware, software, network and/or IS policies and documentations. Typically, a CMDB automatically detects all components/CIs within an IT infrastructure/environment and keeps track of changes as they occur. CMDB provides data about these components in an organized way, making it easier for an organization to review and evaluate the data.

source: Adaptive Dynamics

Characteristics of CMDB

CMDB is only as good as the data it contains. The data must be accurate, regularly updated, and available to associated processes in order for it to be useful. Other characteristics of a useful CMDB include the ability to:

• Simplify the coordination and reconciliation of input from multiple data sources.
• Unify data through automation or federation, identify CI duplication, and correct exceptions.
• Minimize costs and errors through reduction of manual input.
• Provide clear views of CI relationships for Change, Incident, and Problem Management.
• Support Asset Lifecycle Management.
• Provide the flexibility to scale in order to support additional CIs.
• Establish and maintain relationships and application dependency mapping.
• Support dynamically changing environments.
• Improve efficiency and stability through better visibility of CIs.
• Reduce risk and improve security because every CI is recorded and monitored.
• Improve compliance with business rules, monitoring, and auditing, including warrantee and license tracking.
• Develop accurate budgets for future purchases.
• Provide easy access to data.

CMDB Challenges

While not particularly highly visible, a well-managed Configuration Management Database (CMDB) provides organizations with tremendous value. In addition to this value, a CMDB requires an organization to take responsibility for keeping it fit-for-purpose. Hewlett Packard Enterprise (HPE) sponsored a leading analyst firm to poll 100 IT executives on CMDB and discovery tools. The most interesting findings on CMDB challenges are listed below:

• Reconciling data between multiple discovery tools or databases: A CMDB is a great place to consolidate information, as multiple business functions, including IT services, operations and asset management use a CMDB. Since most CMDBs are only populated using discovery tools, this data must be verified and augmented using multiple data sources to make it useful to all relevant functions.
• Achieving accurate discovery in dynamic environments (clouds, containers): Virtual, cloud and containerized systems can exist for short periods of high demand, during which their existence must be extracted from log files. These virtual systems must have their configurations verified for billing, software license use and security vulnerabilities, similar to physical servers.
• Maintaining human expertise required for CMDB maintenance and updates. CMDB maintenance is a skilled task. Duplicate and missing assets must be accounted for, and attribute values associated with each asset record or Configuration Item (CI) must be populated with the most reliable values. Multiple potential values must have any conflicts or inconsistencies resolved. Large CMDBs containing thousands of values require skilled people who can reliably evaluate conflicts when specifying precedence rules.
• Compliance-related concerns with maintaining CI data: Vendors often surprise businesses with license compliance audits, which can be allayed with an accurate CMDB. If you don’t have your own reliable license count, then you will have to apply resources internally to verify this. Alternatively, you will have to use the vendor’s figures, which may mean you are paying a premium. At a more serious level, the CIO is required to maintain an accurate count of IT assets to avoid the possible impact of Sarbanes-Oxley section 404, which mandates adequate financial reporting.
• Costs (human/system) of maintaining accurate CI data: The high cost of maintaining the accuracy of the data in a CMDB increases exponentially against increases in asset volume. Automating this task requires the maintenance of complex precedence rules at a CI attribute level. True accuracy requires a minimum of 2 or more data sources in addition to the source CMDB records. The cost of manual reconciliation is prohibitive once asset numbers increase to thousands, and is prone to human error.

Configuration vs. Asset Management

One very common challenge, as mentioned earlier, is taking a purely “Asset Management” approach to Configuration Management. This often occurs duplicate data frequently appears in both the CMDB and Asset Management database. While it’s true that both systems may include the same asset or configuration items, the purpose of the systems are very different.

• Asset management monitors and manages something of tangible or intangible business value through its lifecycle from purchasing, to operating, to eventual disposal. Tangible assets can include laptops, routers, printers, and software applications that are also part of the CMDB, and/or desks and chairs and other items that are not part of a CMDB.
• Configuration Management can be considered a larger initiative than Asset Management. Configuration Management maintains information associated with CIs, such as associated configuration attributes and relationships, that are necessary to effectively deliver an IT service. Configuration Management also performs the functions of managing CI interrelationships, CI status, and the impact of a change on associated CIs. Several other ITIL processes rely on the CMDB data to function.