RHCE Interview Question Cron vs Anacron

Some RHCE Interview questions for all RHCE certified candidates appearing for interview. These RHCE interview questions are not the only questions they can expect in their interviews, but they provide a basic guidelines / jumping point from where to start.

Based on our feedback from Network Nuts RHCE certified students, these are some of the very commonly asked RHCE interview questions.

What is the difference between cron and anacron?

  • Cron job can be scheduled by any normal user while Anacron can be scheduled only by the super user (root)
  • Cron expects the system to be up and running while the Anacron doesn’t expect the system to be up and running all the time. In case of Anacron, if a job is scheduled and the system is down that time, it will execute the job as soon as the system is up and running.
  • Cron is ideal for servers while Anacron is ideal for desktops and laptops.
  • Cron should be used when you want a job to be executed at a particular hour and minute while Anacron should be used in when the job can be executed irrespective of the hour and minute.
  • anacron can run tasks only once a day (or less often such as weekly or monthly). In contrast, cron allows tasks to run as often as every minute (but does not guarantee their execution if the system goes down).

anacron was originally conceived and implemented by Christian Schwarz in Perl, for the Unix operating system. The current implementation, in C, was written by Itai Tzur and is actively maintained by Sean ‘Shaleh’ Perry.