Why do I need a Configuration Management Database (CMDB)?
Configuration Management is an essential element of the ITIL Service Management model. The question is do you already have everything you need in your current databases?
What about Asset Registers?
An Asset Register alone almost certainly does not provide sufficient information to support Configuration Management. Typically it will contain details of the assets that make up the IT infrastructure and information to financially manage those assets. In other words it is a list of what you have and their associated costs. It does not tell you how those assets are used within the Business.
What about Inventory Databases?
What about the Inventory database? Again this is more of a stock management tool than anything else. It would address such things as how many items are in stock, preferred suppliers, order quantities etc. You can conclude that the Inventory database does not tell you how the assets support the business either.
What does a CMDB tell us about Assets and their effect on the Business?
A CMDB is similar in some ways to the two databases above. However it’s functionality and content is way in excess of either the Asset or Inventory databases.
For example a CMDB contains details of the configuration items (CI’s) that make up the IT infrastructure including details of their attributes, ITSM records (incident, problem, etc), SLA’s and contract information, other relevant records such as location and additional documentation.
The key to the CMDB is that it provides the relationship between all this information and the assets to make up a configuration item that may have several parts to it rather than treating the assets as ëstand aloneÃ. This way we can see how particular services are delivered.
What does a CMDB do?
A CMDB allows Service Management to control all of the IT infrastructure components. It also provides important information to the other ITIL areas. Using a CMDB also means there is one place that can provide answers about any element of the infrastructure.
A CMDB means you have the information to hand to perform problem management and define processes. It also means you can plan projects with all the relevant data in place.
The functionality of the CMDB puts the focus back on the business as you can now see the impact of particular configuration items on particular services. As well as this, the relationships built up within the CMDB allow the management of the quality of those services so SLA’s etc can be met.
Do you need another database?
A CMDB where possible should be a single integrated database. However as many companies have legacy databases such as the Asset Register and Inventory Database, a logical CMDB would consolidate the data in several physical databases.
This allows different views and data to be presented to specific users within the company. For example someone on the Help Desk will not need the same information as a Financial Manager.
