romana Caesaragusta
3.2.1 La conquista y aculturación
The Practical steps and guidelines to follow when documenting the CMDB blue- print can vary between each organization, depending on the goals you are trying to achieve or the issues you are aiming to resolve. But one constant element of this equation remains that you must obtain the right value versus the complexity of building and managing your future CMDB in ServiceNow®.
One way to define the CI attributes that you will maintain in the CMDB versus those that will reside in federated data stores is to establish a guideline based on Value vs. Complexity to maintain, as seen in the image below:
In the following sections, we will dive further into understanding the components of a CMDB blueprint, which can be simplified as:
• Business Services structure
• Related processes requirements
• CI types to include
• CI attributes to manage
• CI relationships to control
2.4. 1 I D E N T I F Y Y O U R B U S I N E S S S E R V I C E S
& M A P P I N G L A Y E R S
Services are defined in various places, and not all business services are defined and available in the current service catalog. Also, services are often referred to with application’s name.
• Definition of a service, per ITIL: A means of delivering value to customers by facilitating outcomes customers want to achieve.
• Definition of a service, per us: Any IT technology service made available to constituents in the context of their role(s), whether provided by central IT units or by some other supplier.
Identify requirements that specify how the service catalog will leverage the relation- ships between services and the underlying CIs. Understanding which CIs relate to a service enables you to better meet SLAs and allows you to conduct service-based costing during the design workshops. The analysis of the following questions will enable you to determine the types of attributes required to include in the CMDB design.
• A good understanding of the types of services your organization offers helps establish the CI structuring and relationships.
• Knowing the customers for the services you provide helps define CI relation- ships or attributes, or both.
• Understanding the services and infrastructure each service offerings relies on helps determine the CI structuring and relationships.
• Understanding service commitments helps define the CI attributes.
• Reporting requirements for effective delivery management helps define the CI Attributes.
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The enterprise architecture approach is a layered view providing a natural way to look at the service-oriented models. The main objectives of EA are:
• Includes a formal description of a system, or a detailed plan of the system at component level to guide its implementation
• Document the structure of components, their inter-relationships, and the prin- ciples and guidelines governing their design and evolution
The business service depends on a network service, an application service, and so forth. By defining the business services as a CI in the CMDB and relating them to the technology services and the application services, will aid in identifying the impact of incidents and problems that are recorded against the infrastructure CIs or the application CIs to the business service.
FIGURE 19 – SERVICE ARCHITECTURE LAYERS
The service catalog includes specific business services to be available for use by the customer. These services are offerings that are bundled and consumed as requests on the portal or the regular application view of a Service Catalog.
The CMDB is a very effective tool, allowing viewing of information from both the service and infrastructure perspective. The following relationships were established to ensure that the CMDB will support an effective delivery of business services.
The CMDB designs often overlook important service management attributes. Sam- ple service management attributes must include the following, as discussed during the workshops:
• Service level targets and priority
• Service entitlement information (hours of service, required approvals, etc.)
• Service notifications, communication information, etc.
• Service owners (by their job titles, for example)
• Service maintainers
• Service managers (by their job titles, for example)
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FIGURE 20 – SERVICE MAP VS. SERVICE OFFERINGS
2.4.2 IDENTIFY REQUIREMENT S B Y PROCES S
SACM is the foundation process that endeavors to provide an accurate and logical model of the IT infrastructure as well as the relationships that exist between com- ponents, systems and provided services.
It is one component of the larger IT Service Management vision that seeks to ensure Business Services are aligned to business needs. It also provides the core data used in Incident resolution, Problem analysis, Change Management, Release Management development and design. It is important to understand that the processes are inter- related because the IT infrastructure being managed is also interrelated.
2.4.2. 1 C h a n g e M a n a g e m e n t
• Change requests to implement a new component (used for impact and risk assessments of a proposed change).
• Inbound and outbound CMDB controls and governance.
• The CMDB breaks down the barriers between IT and the business. The infor- mation removes silos and helps people, processes, and technologies work more efficiently together.
• As the complexity of the IT infrastructure increases, the CMDB containing infor- mation about all the CIs and how they work together will help avoid downtime, by more efficiently planning and better appreciating how those changes affect the business services.
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• The CMDB will aid in better risk assessments and improve security. Use the CMDB data to assess the risks to the business associated with known vulnerabilities on servers and installed applications, which will assist in prioritizing changes on business services.
• Helps keep track of any changes in software. The data from the CMDB aids in determining if there are any unauthorized or illegal software being used.
• The CMDB uses the concept of versioning. This allows the CMDB to track the historical states of a CI over time and to determine recommendations for improvements to the business services.
• The various states of CIs can be compared to see what changes were recorded as of their evolution.
2.4.2.2 I n c i d e n t M a n a g e m e n t
• Helps to determine customer impact and assists with determining priority and severity of a failing component.
• Provides client and service criteria, as well as severity and priority information for configuration components based on service level objectives.
Usually, the lack of information found in the CMDB and the multiple operational toolsets used for monitoring, results in the following:
• Longer time to consolidate and detect issues.
• Multiple configurations to maintain in various places.
• Events at the Service Desk are not opened automatically.
• Notifications and escalations not automated.
• No correlations between events and no automation to repair known issues.
FIGURE 21 – INCIDENT MANAGEMENT WITHOUT CMDB
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FIGURE 22 – INCIDENT MANAGEMENT WITHOUT CMDB
2.4.2.3 Av a i l a b i l i t y M a n a g e m e n t
• Provides core data such as relationships between components to enable design of reporting and subsequent measurement of business services.
• Provides a central information repository that links availability, reliability and maintainability of services to the underlying IT components.
2.4.2.4 S e r v i c e L e v e l M a n a g e m e n t
• Identifies the IT infrastructure components that are required for the delivery of services to the customer, further allowing for accurate establishment and measurement of the objectives in a Service Level Agreement (SLA).
• Provides CI relationship data that links SLAs to customers and to all related CIs that are required to provide the service the Customer pays for.
2.4.2.5 S e r v i c e C a t a l o g
• Inventory of services (Services as CI’s) including business service, applications and technology services
• Presents configuration information about the services the clients are entitled to.
• Provides configuration information about the components used to deliver ser- vices to clients.
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2.4.2.6 P r o b l e m M a n a g e m e n t
• Enables determination of components affected because of another failing com- ponent.
• Provides the IT infrastructure data required to identify root cause and course of action for problems.
• Asset and inventory tracking.
• Utilizes the same core data and are likely to interface for supporting license management efforts.
• Enables Operating Level Agreements (OLAs - with internal IT groups and exter- nal service providers) and Underpinning Contracts (UCs - with external service providers) showing customer ownership.
2.4.2. 7 B u s i n e s s C o n t i n u i t y
• Provides the baseline snapshot of the IT infrastructure which could assist in the recreation of an environment in the event of a disaster or major interruption to service delivery.
• Stores information about the IT infrastructure components, their configurations, and their dependencies to each other and key business processes.
• Identifies the priority and the agreed-upon minimum level of business operation following a major service disruption.
• Tune and/or upgrade various components to provide a higher confidence in high availability.
• Reduced cost of redundant systems by capacity planning at the group or orga- nization level instead of the individual system level.
• Reduced time to resolve capacity-related incidents and problems.
2.4.3 U N D E R S T A N D Y O U R C I C A T E G O R I E S
A CI is any component or service asset that needs to be managed to effectively deliver an IT service. Information about each configuration item is recorded in a configuration record within the configuration management system and, is maintained throughout its life cycle by the SACM process.
Define the optimum level for CIs, both service CIs and infrastructure CIs, in your CMDB. This step helps determine the overall breadth and depth of the structure of your CMDB data model, based on the discovered information, inventory tools, and manually added data.
Construct the CMDB blueprint model using the requirements identified for the Service Catalog, the IT business processes, and the IT service model design, by assessing the data required. Then, present it for approval by your organization.
To better organize the workshops, process documentation, and configuration we recommend splitting your work into the following categories.
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FIGURE 23 – CI CATEGORIES
2.4.3. 1 R E F E R E N C E D ATA
FIGURE 24 – REFERENCE DATA
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Does the IT component represent a specific type of system, user, location, or orga- nizational data that, when represented in a structured format, represents various types of information utilized inside the CMDB.
FIGURE 25 – SERVICENOW© REFERENCE DATA ARCHITECTURE
2.4.3.2 B u s i n e s s S e r v i c e S
FIGURE 26 – CI CATEGORY – BUSINESS SERVICES
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A business service is composed of both physical and logical components. When building the CMDB it’s important to map your services manually but preferably automatically using both discovery tools and the operations solutions at your disposal.
• Service Portfolio: This object represents the top level of the service catalogue and represents a grouping of similar services.
• Service: A service is a combination of IT and non-IT systems that supports a business objective and is perceived by the customer as a coherent whole.
• Sub-service: A sub-service is a discreet component of a service or services.
This level object is only used to provide clarity for complex services.
• System: An integrated composite that consists of one or more of the processes, hardware, software, facilities and people, that provides a capability to satisfy a stated need or objective.
• Sub-system: A discreet component of a system that is usually representative of a single function or purpose. This level object is only used to provide clarity for complex systems.
- Service availability & support - Service Cost
- Service metrics and SLA 2.4.3.3 A p p l i c a t i o n s
FIGURE 27 – CI CATEGORY – APPLICATIONS
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Applications, residing on application servers, are a group of primarily software components that accomplish one or more tasks. This group is also viewed to be considered as a unit. Applications can be as simple as one executable file running on a single computer (such as Microsoft Word) or as complicated as a distributed multi-tier J2EE application, load-balanced across multiple web application servers.
Managing software applications in the CMDB is not an easy task, but it starts with understanding what an application is. To maintain and manage applications inside your CMDB, use the following guidelines.
• Applications: A program designed to perform a specific function directly for the user or, in some cases, for another application program. Applications use the services of the computer’s operating system and other supporting applications.
• Middleware: Software that sits between two or more types of software and translates information between them. Middleware can cover a broad spectrum of software and generally sits between an application and an operating system or a network operating system.
• Application Management: Software that observes, supervises, controls, protects or verifies operations of a system.
• Software Logical Disk: A division of a disk or storage area that is treated by the operating system as a discrete physical disk.
• Network Protocol: Set of rules defining the syntax and semantics of commands and possible responses exchanged between two or more computers on a network, including the order in which the commands can be specified.
• Operating System: Collection of software programs that supervises the exe- cution of other programs and the management of computer resources. An operating system provides an orderly input/output environment between the computer and its peripheral devices. It enables user-written programs to execute safely. An operating system standardizes the use of computer resources for the programs running under it.
• Business Applications: The IT component of a piece of software; either pur- chased, developed, or composed (reuse of other software components) — that provides business functionality of a given service element or system?
- Developed or
- Service-specific commercial off-the-shelf (COTS) application
• Support Software: Is the IT component of a piece of software that indirectly supports a system function, but does not provide the core functionality of a given system?
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FIGURE 28 – EXAMPLE APPLICATION CI TYPE
2.4.3.4 D a t a b a s e s
FIGURE 29 – CI CATEGORY - DATABASES
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When you start adapting ServiceNow®, you will notice that the CMDB includes the following tables by default:
• Database: is a relational database management system (RDBMS) such as SQL Server, Oracle, mySQL, etc.
• Database instances: Are the instances of a database. (SQL: one instance can host several DB’s; Oracle: you can have two instances connecting to the same DB when using RAC)
• Database catalogs: Metadata information - dependent on the technology.
2.4.3.4 S e r v er C o m p u t i n g
FIGURE 30 – CI CATEGORY – SERVER COMPUTING
The Type of systems containing Computing Devices information are divided into the following,
• Hardware server: An electronic device designed to accept data (input), perform prescribed mathematical and logical operations at high speed (processing), and supply the results of these operations (output). A digital computer pro- cesses data as numbers and includes mainframe computers, minicomputers, and microcomputers.
• Hardware processor: The logic circuitry that responds to and processes the basic instructions that drive a computer or server.
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• Hardware memory: The electronic holding place for instructions and data that the processor can reach quickly.
• Hardware network interface: The device that connects the computer with other computers using some type of a communication medium. A network interface may be an Ethernet card, Token ring card, modem etc.
2.4.3.6 I n f r as t r u c t u r e C o m p u t i n g
Data Center Is the IT component a physical location that supports some form of IT operations or houses other IT components
FIGURE 31 – CI CATEGORY –INFRASTRUCTURE COMPUTING
Infrastructure CIs have a unique property – they can be layered in relation to the other CI types they support, particularly servers and applications. Infrastructure computing can be comprised of other infrastructure elements. Consider a business process which utilized a server/client application. The infrastructure elements can be identified in terms of (and in relation to the person executing the process):
• Client – computer system, application interface.
• Network – routers, bridges, firewalls, access points, protocols, etc.
• Data Center – Power, UPS, Rack, Locations, etc.
• Facilities – power, water, cooling, space, etc.
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2.4.3. 7 S t or a g e
FIGURE 32 – CI CATEGORY – STORAGE
Most of the complex CIs to map are related to storage; in the following section, we will illustrate how you can define the CI attributes and data model for storage, fiber and storage arrays systems.
• Hardware Network Attached Storage (NAS): Storage that is set up with its own network address rather than being attached to the department computer that is serving applications to a network’s workstation users.
• Hardware Storage Attached Network (SAN): A high-speed special-purpose network (or sub-network) that interconnects different kinds of data storage devices with associated data servers on behalf of a larger network of users.
• Hardware Storage: The holding of data in an electromagnetic, optical, or elec- tronic form for access by a computer processor.
• Physical Disk: A storage medium consisting of a spinning disk coated with magnetic material for recording digital information.
• Disk Array: A enterprise storage system that contains multiple disk drives. It is differentiated from a disk enclosure in that an array has cache and intelligence so can perform functions like RAID and virtualization.
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Components of a typical disk array include:
- Disk array controller - Cache
- Disk enclosures - Power supply
• Hardware Disk Enclosure: A computer storage device designed to contain physical disk drives. The term is normally used to differentiate such a device from a more advanced disk array. Therefore, a disk enclosure is a simple con- tainer, sometimes with a power supply, but very little intelligence.
2.4.3.8 B a c k u p
The attributes are categorized mainly as CI type, CI status, common hardware attri- butes, software attributes, backup system attributes, and other attributes. A domain consists of a master server with one or more media servers and storage units. A media server may be on the same machine as master or on a different one. Storage units are owned and monitored by the master server, while the media server is responsible for doing the backup of data from the client to the storage unit. All servers which are backed up by the master server are called clients. A storage unit is represented by:
• A storage unit CI is used as target for backup image by media server CI
• A storage unit CI communicates with media server CI
• A storage unit CI is controlled by media server CI
FIGURE 33 – CI CATEGORY – BACKUP
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2.4.3.9 E n d - u s e r C o m p u t i n g
FIGURE 34 – CI CATEGORY –END-USER COMPUTING
Your CMDB must be designed to enable the centralized management of the finan- cial, contractual and demographic data relating to hardware Assets and end-user computing related CIs such as Mobile phones, Workstations, monitors, etc.
The same data used by Assets will then be found in the CMDB tables, this will enable you to make informed decisions regarding how assets can be used more effectively, when to retire or cascade and help in budget exercises to determine future needs of the Business based on the existing baseline.
It’s recommended to integrate with discovery tools or use ServiceNow® discovery to discover your Hardware assets, populate the CMDB and then run hardware recon- ciliation to identify any disparities in the baseline to verify you have control over the environment and reduce the likelihood of rogue systems from being introduced or existing on the network and to also identify any missing hardware such as mobiles, laptops, etc.
2.4.4 I D E N T I F Y A T T R I B U T E S B Y C I T Y P E / T A B L E C L A S S
The configuration management database (CMDB) employs the following tables:
• The core Configuration Item [cmdb / cmdb_ci] tables, which stores the basic attributes of all the CIs.
• The CI Relationship [cmdb_rel_ci] table, which defines all relationships between CIs.
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When you design your CMDB, there are 3 types of CI Attributes to consider:
ATTRIBUTE
TYPE DEFINITION EXAMPLE
• ID
• Name
• Owner CORE Mandatory attributes that apply to every
CI Type in the CMDB. Supporting attributes that are unique to • Model a type/class of CIs. • Manufacturer CLASS Categories are a special class of CI that • Serial number
pass on attributes based on inheritance,
through parent-child relationships. • Document
• Version
• Author
• Editor
CUSTOM [OPTIONAL]
Complementary attributes unique to a specific CI to provide detailed informa- tion not expressed in core or class based attributes.
Server ABC123
• Last security audit date/time
• Operator minimum security clearance level
Attributes are data elements that describe CIs, much like adjectives that describe
Attributes are data elements that describe CIs, much like adjectives that describe