Analyzing log files

　　Error log file formats

　　Error log file entry examples

Configuring advanced logging

　　Debug logging

　　　　Switching binaries at runtime

　　Using access logs for debugging

Common configuration errors

　　Using if instead of try_files

　　Using if as a hostname switch

　　Not using the server context to best effect

Operating system limits

　　File descriptor limits

　　Network limits

Performance problems

Using the Stub Status module