Troubleshooting Logs

30 Minutes

10 Questions

The Troubleshooting Logs Assessment evaluates a candidate's ability to diagnose and resolve technical issues by analyzing system, application, network, and security logs. This test measures practical problem-solving skills in identifying root causes, interpreting error messages, and applying the correct resolution strategies.

Skills Tested
- Log analysis and interpretation (application, system, network, and security logs)
- Identifying infrastructure vs. application-level issues
- Troubleshooting common errors (port binding, SSL failures, database deadlocks, API failures, etc.)
- Debugging server, network, and application issues using logs
- Root cause analysis (RCA) and problem resolution strategies
- Understanding firewall, DNS, and network-related failures

Example Question:

Multiple-Choice

A developer attempts to restart an application server after making some updates. However, the application fails to start, and the following logs appear:

2025-03-05 15:10:01 [INFO] Starting application on port 8080...
2025-03-05 15:10:02 [ERROR] java.net.BindException: Address already in use (Bind failed)
2025-03-05 15:10:03 [INFO] Retrying in 5 seconds...
2025-03-05 15:10:08 [ERROR] java.net.BindException: Address already in use (Bind failed)
2025-03-05 15:10:09 [FATAL] Application failed to start due to port conflict.

System Logs:

2025-03-05 15:09:55 [KERNEL] Process 12345 (webapp) is listening on port 8080
2025-03-05 15:09:56 [KERNEL] Attempt to bind port 8080 failed: Address already in use

What is the most likely cause of this issue?

Answers

1. The application is misconfigured and is trying to bind to an invalid IP.

2. The firewall is blocking access to port 8080.

3. The database connection failed, causing the application to crash.

4. Another instance of the application is already running on port 8080, preventing the new one from starting.