What is a Tiered Logging Strategy?
A tiered logging strategy involves building a structured approach to collecting, storing, and managing logs. It defines them at different levels or “tiers” based on their importance, relevance, access needs, and retention requirements.
Why Is a Tiered Logging Strategy Important?
Not all data is of equal value. Tiering data based on relevance is a useful way to classify logs, making it easier to locate and retrieve specific or timely data.
Some data is frequently required and should be quickly available. Other data may only be retained for compliance purposes, is seldom accessed (if ever), and can be treated as at an archival level. Everything else will fall somewhere between these two points.
There may also be a cost component to how you access and store your data. If that is the case, then tiering allows you to prioritize which information receives faster (more expensive) processing services and what goes into cold storage at vastly reduced storage costs.
How Does a Tiered Logging Strategy Work?
Different organizations and vendors may use different terminology for the tiers, such as critical, real-time, priority, and, at the other end, archival, historical, or even cold storage. Regardless of the terms, the idea is to separate different types of data based on criticality, time sensitivity, frequency of access, or a combination thereof.
Here’s a breakdown of what a tiered logging strategy might look like:
Tier 1 – Critical Logs
Logs that are crucial for real-time monitoring, alerting, and incident response. These logs are often related to critical system errors, security breaches, or service failures and when immediate access is required.
Access – Frequent
Storage – High-availability, low-latency systems for real-time access.
Retention – Short-term, for immediate detection and resolution; may be archived for critical incidents.
Tier 2 – Operational Logs
Logs that provide insights into the daily operations of the system, such as user activities, system events, or API calls. Require continuous access, but not normally at the priority of critical logs.
Access – Frequent
Storage – Medium-performance systems, balancing cost and access times.
Retention – Medium-term, for troubleshooting, performance analysis, or capacity planning.
Tier 3 – Audit and Compliance Logs
Logs that track changes and access patterns, especially important for regulatory compliance, security audits, or forensic analysis.
Access – Infrequent
Storage – Cost-effective solutions; real-time access not needed.
Retention – Long-term, often due to legal or regulatory requirements.
Tier 4 – Archival Logs
Older logs that might not be immediately necessary but are kept for historical analysis, long-term trends, or backup purposes.
Access – Seldom
Storage – For historical analysis, long-term trends, or backup.
Retention – Varies; may extend for years.
Summary
Implementing a tiered logging strategy requires understanding the operational, security, and business requirements of the organization and the data it collects. Not all data is of equal value; using data tiers as a way to classify logs makes it easier to locate and retrieve specific, relevant, and/or timely information. By separating logs into data tiers, you can prioritize information for quicker access and processing. Less important or infrequently accessed data can be ‘frozen’ at reduced costs but takes longer to retrieve. User needs and data requirements vary greatly, so structuring data in tiers optimizes access and costs. Proper tools and solutions, like log management systems or SIEMs, will aid in executing this strategy efficiently.
