LPI 102-500 Practice Test - Questions Answers, Page 8

Explanation:

The correct crontab entry to execute the script chklog three times per month between 3 p.m.and 5 p.m. is:3 15,16,17 * * * chklogThe crontab entry has five fields that specify the time and frequency of the job, followed by thecommand or script to be executed. The fields are:Minute: the minute of the hour when the job should run, from 0 to 59Hour: the hour of the day when the job should run, from 0 to 23 (in 24-hour format)Day of month: the day of the month when the job should run, from 1 to 31Month: the month of the year when the job should run, from 1 to 12Day of week: the day of the week when the job should run, from 0 to 6 (where 0 and 7 areSunday)The asterisk (*) means any value, and the comma (,) means a list of values. Therefore, thecrontab entry above means:Run the job at the 3rd minute of the hourRun the job at the 15th, 16th, and 17th hour of the day (which are 3 p.m., 4 p.m., and 5 p.m.)Run the job on any day of the monthRun the job on any month of the yearRun the job on any day of the weekThis will execute the script chklog three times per day, every day of the month, and every
month of the year, which is equivalent to three times per month.The other options are incorrect because:A . This will run the job at any minute of the hour, but only at the 3rd, 4th, and 5th hour of theday (which are 3 a.m., 4 a.m., and 5 a.m.), and only on the 1st day of the month.B . This will run the job at the 3rd minute of the hour, but only at the 3rd, 4th, and 5th hour ofthe day (which are 3 a.m., 4 a.m., and 5 a.m.), and only on the 1st day of the month.D . This will run the job at the 0th minute of the hour (which is the top of the hour), but only atthe 15th, 16th, and 17th hour of the day (which are 3 p.m., 4 p.m., and 5 p.m.), and only on the1st day of the month.E . This will run the job at any minute of the hour, but only at the 15th, 16th, and 17th hour ofthe day (which are 3 p.m., 4 p.m., and 5 p.m.), and only on the 1st day of the month.Crontab Explained in Linux [With Examples]'crontab' in Linux with Examples - GeeksforGeeksLinux Crontab Command Help and Examples - Computer HopeCrontab in Linux with 20 Useful Examples to Schedule Jobs - TecAdminLinux crontab tutorial with Examples - Linux Tutorials - Learn Linux ..