Configuration management helps engineering teams build robust and stable systems through the use of tools that automatically manage and monitor updates to configuration data. Complex software systems are composed of components that differ in granularity of size and complexity. For a more concrete example consider a microservice architecture. Each service in a microservice architecture uses configuration metadata to register itself and initialize. Some examples of software configuration metadata are:
- Specifications of computational hardware resource allocations for CPU, RAM, etc.
- Endpoints that specify external connections to other services, databases, or domains
- Secrets like passwords and encryption keys
It’s easy for these configuration values to become an afterthought, leading to the configuration to become disorganized and scattered. Imagine numerous post-it notes with passwords and URLs blowing around an office. Configuration management solves this challenge by creating a “source of truth” with a central location for configuration.
Git is a fantastic platform for managing configuration data. Moving configuration data into a Git repository enables version control and the repository to act as a source of truth. Version control also solves another configuration problem: unexpected breaking changes. Managing unexpected changes through the use of code review and version control helps to minimize downtime.
Configuration values will often be added, removed, or modified. Without version control this can cause problems. One team member may tweak a hardware allocation value so that the software runs more efficiently on their personal laptop. When the software is later deployed to a production environment, this new configuration may have a suboptimal effect or may break.
Version control and configuration management solve this problem by adding visibility to configuration modifications. When a change is made to configuration data, the version control system tracks it, which allows team members to review an audit trail of modifications.
Configuration version control enables rollback or “undo” functionality to configuration, which helps avoid unexpected breakage. Version control applied to the configuration can be rapidly reverted to a last known stable state.