Recently we came across a situation with PureApp enablement, where the partner application installation manager has the capability to capture most of the parameters required for WAS profiling and DB instance configuration. This brought out a scenario that there is a redundant approach between PureApp parameters and application installation parameters for pattern based deployment..
This situation is common for any complex application where the application installation has the dependency on DB and application server availability prior to their application installation .Hence the application installation manager itself will consider automating the WAS / DB2 configurations...
In this case, we have the option of discarding the application installation manager and go with the support from PureApp, which is typically not an acceptable solution for the partner since huge effort went in to building application installation manager.
The alternate option is to have a semi automatic approach of PureApp handling the required VM provisioning and application takes care of installing the complete environment. This approach again needs effort from the Partner to change application installation manager design. It involves considerable effort .
The approach we took is quite a balanced one, where PureApp continues to manage the parameters specific to WAS and DB installation. Also certain other specific parameters required for application installation is also brought under the control of PureApp ( through JSON scripting ) .
Post pattern deployment scenario, PureApp captures the parameter values through a property file ,/etc/virtualimage.properties
Now application installation capitalize these value by reading it from the property file and store it on its own cache . Application installation manager gets the required value automatically from the cache and goes forward with application installation. This approach utilizes both the PureApp and application installation manager capability for effective application installation.
Given the situation where a quick pattern development and deployment was expected, this approach certainly helps.