Challenges maintaining Prometheus LTS

Maintaining a Prometheus Long-Term Storage (LTS) solution presents three main challenges: technical expertise, scalability, and infrastructure optimization. Initially, Prometheus was not designed for long-term metrics storage, prompting various open-source projects like Cortex, Thanos, and M3 to offer solutions. Setting up Prometheus is straightforward, but as infrastructure grows, managing it requires detailed knowledge of cardinality, performance, and PromQL optimization. Scaling involves managing increasing metrics, dashboards, and alerts, necessitating strategies for efficient data collection and storage. Additionally, optimizing infrastructure costs, particularly in cloud environments, demands significant expertise to balance resource allocation with cost-effectiveness. Addressing these challenges requires a comprehensive understanding that must be shared across teams to ensure effective observability and application monitoring.