fcron

fcron is a task scheduler for Unix-like systems, designed as an enhanced replacement for the traditional cron utility. It manages the execution of user-defined commands according to schedules and can also trigger tasks at system boot or after the machine resumes from downtime. This makes it suitable for servers and workstations that are not always online.

Like cron, fcron accepts time-based specifications to schedule jobs. In addition, it stores information about previously run tasks and can compensate for missed executions: if a job should have run while the system was down, fcron can execute it automatically when the system becomes available again. It also offers options to restrict execution based on conditions such as maximum load or time windows, to run jobs with a specified user, and to introduce delays or jitter to reduce startup surges.

Jobs are defined in a configuration file using a familiar, cron-like syntax, with per-job options to control behavior. The daemon monitors the schedule and executes commands in a controlled environment, logging output and status. fcron emphasizes reliability on systems that are stopped or reinitialized irregularly and aims to provide greater predictability than classic cron in such scenarios.

fcron is open-source software available on many Unix-like platforms, including various Linux distributions and BSDs. It is typically packaged by distributions and can be configured to integrate with standard init or service management frameworks.