• Simple: Simple Observer lets you create a single observer. Here, you can configure alerts for a single metric only and set thresholds for multiple severities (critical, major, and minor).
• Composite: Composite Observer lets you combine two or more separate observer using logical operators to further refine your alerts. Here, you can configure alerts for multiple metrics and set threshold for multiple severities (critical, major, and minor) in separate sections and combine those by using the logical operators, such as AND (&&) and OR (||), etc.