Systems and groups are paradigms that help in visualizing the holistic perspective of the enterprise IT infrastructure using composition of multiple targets. Groups model homogeneous targets together, that is, belonging to the same target type, whereas systems model heterogeneous targets. These are two similar perspectives that help the IT staff in mapping business functions to IT infrastructure. These two models supplement each other in combining the management tasks.
The targets in an enterprise can be aligned together based on the target type. For instance, the data storage for a specific business function could be provided by multiple database instances, for reasons of failover or load balancing. As a result, it makes sense to model and subsequently manage these database instances together.
Such a model of logically related homogeneous targets is known as a target group.
For example, in the travel portal example, the database targets orcl1 and orcl2 cater to the U.S. customer base.
The following image depicts that the database instances orcl1 and orcl2 can be combined into a single target group—US Portal Oracle Database Group.
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The primary advantage of combining the various target instances into a target group is the ability to manage multiple targets as one. Even though there are two database instances in the above travel portal in the U.S. region, they can be logically managed as a single target group. This facilitates applying common management tasks on all the members comprising the target group. For example, in the travel portal, the backup of all member targets such as orcl1 and orcl2 within the US-DB-Group can be performed together. The same backup database job can be run for all instances within the same group.
Moreover, the group helps in monitoring the member targets as one entity. As there are two database instances clustered in the U.S. data center to facilitate load balancing and failover, the availability of the database as a whole to the middleware and travel applications can be viewed if they are grouped together. This allows the administrator to ensure that both the database instances do not become unavailable simultaneously.
Grouping related targets together also helps in comparing the target configuration together. Also, policy enforcements are simplified by modelling the related target instances together as a group. As an illustration, at the enterprise level, it might be mandated that all the Oracle database instances deployed for the travel portal must be of a certain version and patch-set level. The database administrator in the U.S.
data center can easily compare the current version and patch-set deployments of the databases within the target group and can therefore enforce the above policy.
The targets within an enterprise can also be related by various other categories.
These categories can be based on parameters such as lines of business, functions, geographies, and so on. When multiple targets interact with each other to provide a business solution, it is natural from a management point of view to combine the various components into a logical entity. This paradigm of modeling disparate but related targets as one entity is known as system modeling.
The targets within a particular geographical location can be related together into a single entity for easiness in management operations. For instance, combining all the targets within the Singapore data center helps in visualizing all the components, providing business functions to the APAC users. From a world-wide view, such a geographical perspective aids in getting a snapshot of the components. This snapshot can be used to drive operational efficiency such as utilization across all business functions provided within the geography. Such an aggregation of all the components within a specific location also facilitates monitoring the various business functions that are provided within the geography.
The following image illustrates the aggregation of different but logically related targets within the same geographical location in the travel portal. Different targets such as Portal app, Weblogic Server, Oracle Database server, and the related hosts in Singapore are combined together into a single system target—APAC TRAVEL SYSTEM.
Another criterion for relating different targets within an enterprise into a system can be functional support. For example, within a travel portal, it makes sense to combine the logically related targets such as the middleware targets, related database targets, and associated hosts, which provide credit card validation and payment functions into a single system.
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One of the significant benefits of modeling a system is the ability to view the difference in configuration between two time intervals. As described in the target modeling section, each target has configuration parameters. These parameters may get changed as part of the configuration management operation or as part of maintenance operations. By comparing the changes in the configuration of the system as a whole between two different intervals of time, any misbehavior in performance of the topology can be easily nailed down. For instance, after a recent patch-set deployment in one of the related application servers, if the credit validation and payment functions show poor performance, the diagnosis is aided by a consolidated view of all the configuration changes in the recent past within the system.
Modeling components that interact to provide a related business function into a system have added benefits such as scheduling the same maintenance windows for all the related targets. For example, all the targets that interact to provide the credit card validation function within the travel portal. They can be restarted together after a critical patch-set deployment.
Once a system has been modelled, it becomes easier for individual target type administrators to determine the potential impact of a specific operation on a target instance. For example, a database administrator who manages the database instances of the credit card validation function might contemplate a restart. By viewing the associated system, it becomes fairly easy to identify other targets such as application server, application deployments, and so on, which could be impacted due to this operation. Hence, a view based on business function allows individual stakeholders to determine the business impact of IT operations.
Both the systems and groups model aim at visualizing the related components of the infrastructure stack as one entity. By doing so, there are some inherent advantages.
They are as follows:
Associating related targets into a single entity allows the administrators to view the availability of all the targets together
Combining related targets helps in rolling up the key policy violations across the topology to be looked at
Aggregation of related targets also helps in visualizing deviations from expected thresholds of metrics collectively
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However, the systems model is significantly different from the group model described above. While a group target comprises of homogeneous targets, the systems model comprises of logically related heterogeneous target instances.
A group target enables similar operations across targets of the same type and is primarily intended to model clusters providing failover and load balancing functions. A system target is intended to be a single point of reference for a particular line of business or geography even while managing multiple targets belonging to different types.