Why is my EC2 Windows instance down with an instance status check failure?

Short description

AWS monitors the health of each EC2 instance with several different status checks. When a status check fails, an EC2 instance is unreachable.

An instance status check can fail when there's an issue with the operating system (OS) that runs inside the EC2 instance or the attached network adapter.

The following are some additional reasons why an instance status check might fail:

• Networking or startup configuration issues
• Exhausted memory
• File system issues
• Failure to boot the OS
• Failure to mount volumes correctly
• Incompatible drivers
• CPU exhaustion

If both the instance and system status checks fail, then see Why is my EC2 Windows instance down with a system status check failure or status check 0/2?

Resolution

To resolve the errors that you receive, use the following troubleshooting options:

• Review the instance screenshot to verify whether the instance boots up. If the screenshot shows that the instance is stuck in a boot loop or you see a BSOD screen, then contact AWS Support.
• In the instance screenshot, check for the network icon on the bottom right corner. If there's a warning icon or red cross, then attach an additional elastic network interface to the instance.
• Review the console log output to check for reported OS crash events.
• Check the resource utilization metrics such as the Amazon CloudWatch metric for CPU utilization. When CPU utilization is exceptionally high, it can cause status checks to fail because of limited resources. To reduce CPU utilization, restart the instance.
• If any recent OS-level changes caused status checks to fail, then perform a restore. Use the EC2 Rescue tool's Last Known Good Configuration (LKGC) feature.
• Review the system logs.

For more information, see Troubleshoot issues with Amazon EC2 Windows instances.

Note: You can also use EC2Rescue for Windows Server to diagnose and troubleshoot issues.

Related information

Troubleshoot an unreachable Amazon EC2 instance

Troubleshoot issues connecting to your Amazon EC2 Windows instance

Why is my EC2 Linux instance unreachable and failing its status checks?

How do I diagnose high CPU utilization on my EC2 Windows instance when my CPU is not being throttled?

Create a network interface for your EC2 instance