Note Many processing jobs, particularly those batch jobs affecting the database, need to be scheduled to run at quieter periods. Some need to be run at regular intervals throughout the working day. The UNIX system process known as cron can be used to automate repetitive tasks.
Cron is a system facility that enables you to schedule the regular or repetitive execution of operations on a time and date basis. Cron is started automatically at system boot. You can also use it to automate daily or weekly operations such as backup and disk clean-up.
The cron process enables the system manager to set up jobs that will run automatically on pre-determined days and times. It may be used to schedule overnight or weekend jobs, or jobs that need to run at regular intervals during the day.
The cron process reads a file known as the root cron file into memory and executes the jobs it contains at the times that are specified.
cron files can potentially exist for each UNIX
account on the system. However, for ease of maintenance and support, Capita
recommends that a cron file exists only for the root user (or superuser).
Note
An alternative solution is to use the UNIX command known as at, as this allows one-off jobs to be scheduled.