1. Graylog: Graylog is a powerful open-source log management tool that allows organizations to collect, process, store, and analyze logs from various sources.

2. Wazuh: Wazuh is an open-source security monitoring solution that helps organizations detect and respond to security incidents, providing log analysis, file integrity monitoring, intrusion detection, and more.

3. Data Collection and Sources Integration: Graylog offers extensive flexibility in data collection and integration, allowing the collection of logs from various sources, including syslog, GELF, and more, making it ideal for centralized log management. Wazuh focuses primarily on security-related logs and has integrations with security-specific sources like OSSEC agents, making it well-suited for security monitoring.

4. Alerting and Notifications: Graylog provides built-in alerting and notification capabilities that can be customized based on various criteria, including log patterns, field values, and more. Wazuh offers an extensive set of predefined correlation rules and alerts for security-related events, allowing for real-time alerting and reporting on potential security incidents.

5. Log Analysis and Search: Graylog offers a powerful search and analysis functionality, allowing users to quickly search and filter logs based on various criteria, as well as create custom dashboards and visualizations for data analysis. Wazuh provides log analysis capabilities, focusing more on security-related events, allowing users to search and analyze logs for potential security threats.

6. Scalability and High Availability: Graylog is designed to be highly scalable and can handle large volumes of log data, providing options for clustering and distributed setups for high availability. Wazuh can also be deployed in a distributed architecture, allowing for scalability and high availability, ensuring constant monitoring across different nodes.

7. User Interface and User Experience: Graylog offers a user-friendly web interface with an intuitive design, making it easy to navigate and use. Wazuh provides a web-based interface with a focus on security events, providing visualizations and reports specifically tailored for security monitoring.

8. Community and Support: Graylog has a large and active community, offering extensive documentation, community-contributed plugins, and support from the community. Wazuh also has an active community and provides documentation, but the community resources are relatively smaller compared to Graylog.

In Summary, Graylog and Wazuh are both powerful open-source solutions, but Graylog offers more flexibility in log collection and sources integration, while Wazuh is specifically focused on security monitoring, providing predefined security alerts and rules.