A System for Changing Systems – Part 3 – How Many “Chang-ee”s

As mentioned in the last post, once there is a “whole system” understanding of an application system, the next problem is that there are really multiple variants of that system running within the organization at any given time. There are notionally at least three: Development, Test, and Production. In reality, however, most shops frequently have multiple levels of test and potentially more than one Development variant. Some even have Staging or “Pre-production” areas very late in test where the modified system must run for some period before finally replacing the production environment. A lot of this environment proliferation is based on historic processes that are themselves a product of the available tooling and lessons organizations have learned over years of delivering software.

Example Environment Flow

This is a simplified, real-world example flow through some typical environments. Note the potential variable paths – another reason to know what configuration is being tested.

Tooling and processes are constantly evolving. The DevOps movement is really a reflection of the mainstreaming of Agile approaches and cloud-related technologies and is ultimately a discussion of how to best exploit it. That discussion, as it applies to environment proliferation, means we need to get to an understanding of the core problems we are trying to solve. The two main problem areas are maintaining the validity of the sub-production environments as representative of production and tracking the groupings of changes to the system in each of the environments.

The first problem area, that of maintaining the validity of sub-production envrionments, is a more complex problem than it would seem. There are organizational silo problems where multiple different groups own the different environments. For example, a QA group may own the lab configuraitons and therefore have a disconnect relative to the production team. There are also multipliers associated with technical specialities, such as DBAs or Network Administration, which may be shared across some levels of environment. And if the complexity of the organization was not enough, there are other issues associated with teams that do not get along well, the business’ perception that test environments are less critical than production, and other organizational dynamics that make it that much more difficult to ensure good testing regimes are part of the process.

The second key problem area that must be addresssed is tracking the groups of changes to the application system that are being evaluated in a particular sub-production environment. This means having a unique identifier for the combination of application code, the database schema and dataset, system configuration, and network configuration. That translates to five version markers – one for each of the main areas of the application system plus one for the particular combination of all four. On the surface, this is straightforward, but in most shops, there are few facilities for tracking versions of configurations outside of software code. Even when they are, they are too often not connected to one another for tracking groupings of configurations.

They typical pattern for solving these two problems actually begins with the second problem first. It is difficult to ensure the validity of a test environment if there is no easy way to identify and understand the configuration of the components involved. This is why many DevOps initiatives start with configuration management tools such as Puppet, Chef, or VMWare VCenter. It is also why “all-in-one” solutions such as IBM’s Pure family are starting to enter the market. Once an organization can get a handle on their configurations, then it is substantially easier to have fact-based engineering conversations about valid test configurations and environments because everyone involved has a clear reference for understanding exactly what is being discussed.

This problem discussion glosses over the important aspect of being able to maintain these tools and environments over time. Consistently applying the groups of changes to the various environments requires a complex system by itself. The term system is most appropirate because the needed capabilities go well beyond the scope of a single tool and then those capabilities need to be available for each of the system components. Any discussion of such broad capabilities is well beyond the scope of a single blog post, so the next several posts in this series will look at framework for understanding the capabilities needed for such a system.

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