Examine /etc/anacrontab:SHELL=/bin/sh PATH=/sbin:/bin:/usr/sbin:/usr/bin MAILTO=root # the maximal random delay added to the base delay of...

Understanding the anacrontab Entries:

The /etc/anacrontab file contains the following variables and job definitions:

SHELL=/bin/sh

PATH=/sbin:/bin:/usr/sbin:/usr/bin

MAILTO=root

# the maximal random delay added to the base delay of the jobs

RANDOM_DELAY=45

# the jobs are started during the following hours only

START_HOURS_RANGE=3-22

# period in days delay in minutes job-identifier command

1 5 dailyjob nice run-parts /etc/cron.daily

7 25 weeklyjob nice run-parts /etc/cron.weekly

@monthly 45 monthlyjob nice run-parts /etc/cron.monthly

Variables Explained:

RANDOM_DELAY=45

Specifies that arandom delaybetween 0 and 45 minutes is added to the base delay of each job.

START_HOURS_RANGE=3-22

Jobs are allowed to start only between03:00 (3 AM)and22:00 (10 PM).

Job Delays Calculated:

First Job (dailyjob):

Base Delay:5 minutes

Random Delay:0 to 45 minutes

Total Delay:5 + (0 to 45) =5 to 50 minutes

Second Job (weeklyjob):

Base Delay:25 minutes

Random Delay:0 to 45 minutes

Total Delay:25 + (0 to 45) =25 to 70 minutes

Third Job (monthlyjob):

Base Delay:45 minutes

Random Delay:0 to 45 minutes

Total Delay:45 + (0 to 45) =45 to 90 minutes

Option B: Jobs defined in this anacrontab file can be executed between 15:00 and 22:00

Explanation:

The START_HOURS_RANGE=3-22 setting allows jobs to start between03:00 and 22:00.

Therefore, it's true that jobscan be executed between 15:00 (3 PM) and 22:00 (10 PM).

This statement is correct because the specified time range falls within the allowed start hours.

Oracle Linux Reference:

Oracle® Linux 8: Scheduling Tasks- Section on "Anacron Configuration Files":

"The START_HOURS_RANGE variable defines the time window during which Anacron jobs can run."

Option C: Scripts run by the third job are delayed between 45 and 90 minutes.

Explanation:

The third job (monthlyjob) has abase delay of 45 minutes.

With a RANDOM_DELAY of up to 45 minutes, thetotal delaybefore execution is between45 and 90 minutes.

Therefore, this statement is accurate.

Oracle Linux Reference:

Oracle® Linux 8: Scheduling Tasks- Section on "Understanding Anacron Job Delays":

"Each job's delay is calculated by adding its defined delay to a random value between 0 and RANDOM_DELAY."

Why Other Options Are Not Correct:

Option A:Scripts run by the first job are delayed between 11 and 45 minutes.

Explanation:

The first job (dailyjob) has a total delay between5 and 50 minutes(5-minute base delay plus up to 45 minutes random delay).

Therefore, the statement specifying11 to 45 minutesis incorrect.

Option D:Jobs defined in this anacrontab file are randomly delayed by up to 51 minutes.

Explanation:

The maximum random delay is set by RANDOM_DELAY=45, so the random delay is up to45 minutes, not 51.

Therefore, this statement is false.

Option E:Scripts run by the second job are delayed between 31 and 70 minutes.

Explanation:

The second job (weeklyjob) has a total delay between25 and 70 minutes(25-minute base delay plus up to 45 minutes random delay).

The statement specifies a delay between31 and 70 minutes, which is incorrect because the minimum delay is 25 minutes.

Conclusion:

Options B and C are correct based on the configuration specified in /etc/anacrontab. They accurately reflect the possible execution times and delays for the jobs defined.