Monit

Monit is an open-source utility for managing and monitoring UNIX systems. Monit performs automatic maintenance and repair, executing specific actions in error situations.

★★★★★

5.0(1 ratings)

• Process Monitoring. Monit monitors daemon processes or similar programs running on the local system. It is effective for monitoring services started during system boot, such as mail servers, web servers, or databases. Monitoring includes checking the running state and the ability to restart processes that have terminated unexpectedly.
• System Resource Control. Monit monitors process characteristics and system resource consumption. It analyzes memory usage and CPU cycles by individual applications. This function identifies processes consuming excessive resources, allowing corrective actions in situations such as denial-of-service attacks.
• File and Directory Monitoring. The utility watches files, directories, and file systems on the local host. It detects timestamp changes, checksum alterations (MD5 or SHA1), and size variations. This capability provides a security mechanism by alerting on changes to critical configuration files or system binaries.
• File System Monitoring. Monit checks the status and usage of partitions and file systems. It monitors available disk space and can generate alerts when usage exceeds defined thresholds, preventing disk-full situations that affect system operation.
• Network Connectivity Tests. Monit evaluates network connections to both local and remote servers. It supports tests for TCP, UDP, and Unix domain sockets. It includes protocol-level checks for major internet services like HTTP, SMTP, and others. For unsupported protocols, it allows sending custom data and validating the server's response.
• Program Execution and Verification. Monit can run programs or scripts at specific times, similar to cron. Additionally, it checks the program's exit value and executes an action or sends an alert if this value indicates an error. This feature makes it possible to implement any type of check via custom scripts.
• Global Resource Monitoring. Monit monitors overall system metrics such as global CPU usage, available memory, system load average, and network interface status. It provides a consolidated view of the host's performance and health.
• Automated Actions. Upon detecting an error condition, Monit executes predefined actions. These actions include starting, stopping, or restarting services, executing specific commands, or sending alert notifications. Automatic response reduces service downtime.
• Notifications and Alerts. Monit configures and sends alert messages when anomalous conditions are detected. Notifications can be directed via email or other mechanisms, informing about events such as services down, excessive resource usage, or modifications to critical files.
• Standalone Architecture. Monit operates as a standalone system that requires no plugins or special libraries. It works immediately after installation and integrates with the system's existing infrastructure, including init, upstart, or systemd, using run-level scripts to manage services.
• Container Functionality. Monit can run as PID 1 (init) in container environments. In this capacity, it handles both init responsibilities and service supervision in a single lightweight package, being an alternative for container management.
• Centralized Management with M/Monit. The utility integrates with M/Monit for centralized management of multiple servers. M/Monit expands capabilities by providing a modern user interface that allows monitoring and managing all hosts with Monit from a unified console, accessible from mobile devices.

Monit's development began in the year 2000. It was created by developer Tildeslash. The tool is primarily written in the C language. Its design prioritizes reliability and operational autonomy. The development philosophy focuses on creating a utility that works consistently and predictably, integrating with existing systems without extensive modifications. The software license is the GNU Affero General Public License (AGPL).

Alternatives to Monit:

Total Network Monitor

Total Network Monitor (TNM 2) is a network monitoring software program designed to continuously monitor your local network, individual computers, and services that require careful attention.

Price: Free   Size: 60.8 MB   Version: 6.6.5   OS: Windows

iStat Menus

iStat Menus is an advanced system monitoring application for macOS.

Price: $21   Size: 19.9 MB   Version: 7.10   OS: MacOS

AntiLogger

Abelssoft AntiLogger is security software specialized in the detection and prevention of keyloggers.

Price: $19.95   Size: 10.4 MB   Version: 2025.9.04   OS: Windows