AWS - EC2 FundamentalsYou attempt to SSH into your EC2 instance but the connection times out. Which of the following is the MOST probable reason?AThe instance is running an unsupported operating systemBThe private key file has incorrect permissionsCThe username used is incorrectDThe security group does not allow inbound SSH traffic on port 22Check Answer
Step-by-Step SolutionSolution:Step 1: Analyze timeout causesA timeout usually indicates network connectivity issues, often due to firewall or security group rules.Step 2: Evaluate optionsIncorrect private key permissions or username cause authentication errors, not timeouts.Step 3: Unsupported OS does not cause timeoutIt would cause login failures, not network timeouts.Final Answer:Security group blocking inbound SSH on port 22 -> Option DQuick Check:Timeouts usually mean blocked network ports [OK]Quick Trick: Timeout means port 22 likely blocked in security group [OK]Common Mistakes:MISTAKESConfusing authentication errors with timeoutsAssuming OS incompatibility causes timeouts
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