How would you troubleshoot connectivity issues in AWS?

Connectivity troubleshooting: 1) Check security group and NACL rules, 2) Verify route table configurations, 3) Test with VPC Reachability Analyzer, 4) Check DNS resolution, 5) Analyze VPC Flow Logs, 6) Verify internet gateway and NAT gateway, 7) Test with EC2 Instance Connect or Session Manager, 8) Monitor with CloudWatch metrics.