The paper considers different approaches and tools for system log files analysis. Authors describe typical cases where such analysis is required. Requirements for a multipurpose log analysis tool are stated. Three classes of log analysis tools are discussed: specialized ones, real-time analysis tools and configurable analyzers. Advantages and disadvantages of these tools are summarized. Reviewed tools are assessed in the terms of compliance to the stated requirements. Configurable analyzers are considered to be the most suitable tools for described tasks.

Keywords: system logs, semistructed form, pattern, structure recognition, records filtration