In this new post I would like to introduce a new function added in Image Construction and Composition Tool (ICCT) 1.2; it is the capability to extend a base image available in IBM Smart Cloud Provisioning 2.1 assigning to it multiple “image personalities.”
The “image personality” is a key concept in the cloud paradigm and in exploiting this capability it is possible to create just a single image that can behave in different ways based on the image personality assigned at deployment time.
The benefits of it are:
- reduced number of master images to store/move
- reduced number of master images to patch
This concept is not new since IBM Workload Deployer (IWD) already supports them, in IWD they are referred as “virtual parts,” but what is really new from a customer perspective is the capability to create an image with “multiple personalities”using ICCT.
Let’s explain this functionality by going through a simple scenario.
If I want to make available in the cloud a complex cloud service and it includes multiple tiers, for example a HTTP server, databases and the middleware, the first option might be to create three different master images even if they might have in common the OS and most of the required libraries. But then the first time I will need to apply a patch to the OS or to a required library I will have to apply the same patches to all the three master images, and as you can imagine it is just a waste of time and resources.
So it seems not the best option to proceed, and here is where the concept of “image personality” provides a significant value.
Using ICCT, I can create three different bundles:
- HTTP server bundle
- Middleware bundle
- Database bundle
And when I extend the base image that includes just the OS and the required libraries I can assign multiple personalities to it, where each personality includes a subset of three installed bundles.
For example I can create different personalities:
- Single Node that includes all the bundles
- HTTP Node that includes the HTTP Server bundle
- Middleware Node that includes the Middleware bundle
- Database Node that includes the Database bundle
This is a picture that describes the different personalities in the ICCT user interface.
The new extended image can be deployed in different ways based on the personality selected at deployment time. In fact the personality, chosen in “Configure virtual parts” will drive the activation/configuration only of the bundles that belong to it while the other bundles will not be activated/configured.
This is a picture that describes a pattern based on three images that contain the different personalities in the SCP 2.1 user interface.
This simple example only illustrates the potential of this solution. You can imagine the potential savings and reduction in master image counts and maintenance when you multiply the number of OS platforms, applications and combinations that might exist in a typical production environment.
Image Personalities for master images is only one of the new features found in SmartCloud Provisioning 2.1.
For more information, visit:
- The infocenter for SmartCloud Provisioning 2.1
- What’s new in SmartCloud Provisioning 2.1 (developerWorks)
Please take a look at the IBM Smart Cloud Provisioning 2.1 infocenter to get more details on this support.