Cache Behaviors and TTL Settings
Define path-based cache behaviors, set minimum, default, and maximum TTLs, and use cache-control headers to fine-tune caching.
Cache Behaviors: What Are They?
Cache behaviors are the rules that tell CloudFront how to handle requests for different URL path patterns. Each cache behavior maps a path pattern (e.g., /images/*, /api/*, *.css) to a specific origin and caching configuration.
A distribution has one Default Cache Behavior (matching all paths not caught by more specific behaviors) and up to 25 additional path-based behaviors. CloudFront evaluates behaviors in order from most specific to least specific, then falls through to the default.
Path Pattern Matching
Path patterns support wildcards: * matches any combination of characters including slashes, and ? matches any single character. Examples:
/images/*— all URLs starting with /images/*.jpg— all requests ending in .jpg anywhere in the path/api/v2/*— all API v2 routes/static/??.css— static CSS files with exactly two characters before .css
Behaviors are evaluated in the order listed in the distribution configuration. Put more specific patterns first. The default behavior (*) always matches last.
All lessons in this course
- CloudFront Distributions and Origins
- Cache Behaviors and TTL Settings
- Signed URLs, Signed Cookies, and Geo-Restriction
- CloudFront with WAF and Lambda@Edge