Understand the relationships between Application Service, Model ID, and Application

[melissahill]

Can you please help me understand the relationships between Application Service,  Model ID, and Application?  I am not sure how these work together.  I am also questioning if we need to setup Application Models when we create application services.

Thanks for the help!

Melissa

[Mike Allen]

Let's say you have a website.  That website has various components.  It has a web server, maybe a database, probably an app server, a authentication method, and all these things come together to make your website.  The website is the application service.  The web server (apache or iis or whatever), the db (mySQL, mssql, whatever), the app server, are all applications that server that application service.  I am guessing that the model fits in under the application, and it says, this web server is apache, this db is mysql, etc. etc.

[mikkojuola]

Thanks Mike and hi Melissa,

Adding to what Mike said about Application CIs and Models. Application class in this context can represent different kinds of installed applications on different kinds of servers. Usually on a more detailed level than an "application portfolio" would manage. Application CIs and the other CI Classes extending the application class can be populated by Discovery also. With installed apps, you often have a particular version of the app and that is defined by a Model ID, being the Application model in this case.

So, the Model ID connects the Application CI to assets and product models. Application CI can be linked to either an Application Model or a Software Model. This is defined by the Model Category. What I've understood is that Software models are more for license and asset management while Application models are used in the application development/scrum processes. Honestly, I don't know why there are two different model classes, Application and Software, since they are doing pretty much the same thing. Software models by default have much more details, mostly related to asset management and licensing.

Here's one illustration about the CI-Asset-Model combination.

Cheers,

--Mikko

[theroz]

Hi Mike - 

You make a good point above - we are looking to implement CSDM 2.0 soon. One question though - our current websites are being discovered and populated in CMDB by discovery as website CI records (a child class of cmdb_ci_appl). 

If a record is manually created for a new web site as an application service (cmdb_ci_service_discovered) and discovery creates a web site CI record (cmdb_ci_web_site), you would have two records describing the same configuration item - in this case a web site. Am I correct in my logic? If so, have you experienced this and how did you all handle it? 

[melissahill]

Those are both very helpful.  One remaining question - should the Application Model be on the Application Service record or the Application record, or both?  

In Mikko's example, the Model is used to link to Assets.  What Asset record do you create and manage for Applications?  Is it for the Business Application record?  In which case, the Application Service inherits from the Business Application record, and we don't want to have to change the business application record when we have new versions of the application released, so then we would manage the model at the Application Service level.

In Mike's example, the Application might very well NOT be tied to as asset, but versioning may be important.  Would we also want Application Models associated to Application records? 

This seems like a lot of model maintenance work 🙂

Thanks for your help!

Melissa