Managing configuration files for multiple instances of the same application (same environment)

Question

I have multiple instances of the same engine running as windows services on the same environment and system that just have slightly different connection strings as they point to different queues. Other than a couple of lines in the conifg (XML) the rest of the application is exactly the same (config and binaries). When config changes are made this is done to all instances which is time consuming so I am doing some research into the best method of managing the config files in a scalable and version controlled way. Currently I use a batchfile to copy the default engine directory and config over and then find and replace the individual strings. I'd prefer to have a template config that can be updated that pulls in set variables for the connection strings depending on the instance and environment. I understand that this may be possible using chef, puppet or ansible but to my understanding these are more for system configuration as opposed to individual application files? Does anyone know if this is possible with gitlab or AWS? Before committing to the learning curve I'm trying to discern if one of the aforementioned config management tools would be overkill for this scenario or a realistic solution?

Answer 1

I understand that this may be possible using chef, puppet or ansible but to my understanding these are more for system configuration as opposed to individual application files?

Managing individual files, including details of their contents, is a common facet of configuration management. Chef, Puppet, and Ansible can all do this with relative ease.

Does anyone know if this is possible with gitlab or AWS?

No doubt, someone does. And I anticipate, but cannot confirm, that the answer is "yes" for both.

Before committing to the learning curve I'm trying to discern if one of the aforementioned config management tools would be overkill for this scenario or a realistic solution?

A configuration management system would almost certainly be overkill if the particular task you describe is the only thing you are considering them for.

Currently I use a batchfile to copy the default engine directory and config over and then find and replace the individual strings. I'd prefer to have a template config that can be updated that pulls in set variables for the connection strings depending on the instance and environment.

In the first place, if it ain't broke, don't fix it. On the other hand, if it is broke, and switching to a template-based approach is a reasonable method to resolve the issue, then you can certainly implement that with a for-purpose local script without bringing in all the apparatus of a configuration management system.

In the event that you do decide that the current mechanism needs to be replaced, do, for goodness sake, ditch batchfile. It's one of the worst scripting languages ever inflicted on humanity. PowerShell would be a natural replacement on Windows, but you might also consider Python, or pretty much any programming language you know.