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This article will explain in detail what anacron is and its characteristics. The content of the article is of high quality. Therefore, Xiaobian shares it with you as a reference. I hope you will have a certain understanding of relevant knowledge after reading this article.

What is anacron: Linux? Cron was initially used to automate routine system maintenance, such as replacing log files and updating spam filtering rules. This approach works well for servers and other systems that run 24/7. However, if you want to turn off your computer to conserve resources when you are not using it (common on desktop and laptop systems), you cannot run Cron. Failure to run Cron on a regular basis will generate a large number of log files and cause other problems. Anacron's utilities provide a solution that allows computers to run regular maintenance jobs after each boot, even if these boot times are variable.

What is anacron?

If you're running Linux (or most other UNIX systems) on a desktop or laptop, you're likely to shut down the system frequently. Indeed, some systems may be off longer than they are on throughout the day. This can help reduce electricity costs. For laptops, if you don't have a power outlet on the road, turning them off often can help extend the life of the computer. Unfortunately, this frequent shutdown behavior can cause problems for Linux systems because Linux uses a utility called Cron to run routine maintenance jobs in the background. When these jobs stop running, they cause problems, and over time, the performance of the system becomes lower and lower.

Cron is designed to launch programs at specified times without being attended to. In general, anacron services have two types of Cron jobs (programs run by crons): system Cron jobs, run by the system to perform system maintenance tasks, and user Cron jobs, created by users to perform user tasks. Of these two jobs, the system Cron job is more important. These jobs may include purging stale files in/tmp, replacing log files, updating spam filtering rules, and updating the locate database.

What anacron is, most Linux systems contain a series of cron-related subdirectories in/etc./ The etc/crontab file specifies which jobs Cron should run as system Cron jobs. Typically, this file tells Cron to run scripts located in/etc/cron.hourly,/etc/cron.daily,/etc/cron.weekly, and/etc/cron.monthly at hourly, daily, weekly, and monthly intervals. The exact time to run these jobs is specified in/etc/crontab. For jobs that run daily and at longer intervals, the run time is usually morning. The problem is that desktop and laptop systems are likely to be off at these times.

When a Cron job fails to run, various problems ensue. The exact problem depends on the Cron job that should be running, but problems include, for example, log file enlargement,/tmp directory corruption, and database expiration issues where available software updates or local system commands are stored.

Obviously, it's important to keep Cron jobs running. If you need to shut down a system frequently, you should find a way to avoid these problems. Anacron is the solution to that goal.

About what anacron is and its characteristics to share here, I hope the above content can be of some help to everyone, you can learn more knowledge. If you think the article is good, you can share it so that more people can see it.

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