Do I need external synthetic checks if my infrastructure is already healthy?

Usually, yes—if you care about catching user-facing issues before customers do.

A healthy infrastructure only tells you that servers, networks, and services are up. External synthetic checks tell you whether the actual experience from the outside is working.

Why synthetic checks still matter

They can detect problems that internal health checks often miss, such as:

• DNS or certificate issues
• CDN or edge routing problems
• Firewall/WAF misconfigurations
• Login/payment/API flow failures
• Regional or ISP-specific outages
• Slowdowns that don’t trip basic health metrics
• Broken dependencies that are “up” but unusable

When they’re especially useful

External synthetic monitoring is valuable if you have:

• Customer-facing web apps or APIs
• SLAs/SLOs to meet
• Multi-region or global users
• Critical business flows like checkout, signup, or auth
• Third-party dependencies

When you might skip them

You may not need them if:

• The system is purely internal
• The impact of downtime is very low
• You already have strong end-to-end user monitoring from another source
• Cost/complexity is not justified for a non-critical service

Practical rule

Use this layered approach:

• Infrastructure health checks: “Is the system alive?”
• Synthetic checks: “Can a real user successfully use it?”
• Real user monitoring: “What are actual users experiencing?”

If you want, I can help you decide whether synthetic checks are worth it for your specific stack and traffic pattern.