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anacrontab(5) [centos man page]

ANACRONTAB(5)							   File Formats 						     ANACRONTAB(5)

NAME
/etc/anacrontab - configuration file for Anacron DESCRIPTION
The /etc/anacrontab configuration file describes the jobs controlled by anacron(8). It can contain three types of lines: job-description lines, environment assignments, or empty lines. Job-description lines can have the following format: period in days delay in minutes job-identifier command The period in days variable specifies the frequency of execution of a job in days. This variable can be represented by an integer or a macro (@daily, @weekly, @monthly), where @daily denotes the same value as the integer 1, @weekly the same as 7, and @monthly specifies that the job is run once a month, independent on the length of the month. The delay in minutes variable specifies the number of minutes anacron waits, if necessary, before executing a job. This variable is repre- sented by an integer where 0 means no delay. The job-identifier variable specifies a unique name of a job which is used in the log files. The command variable specifies the command to execute. The command can either be a command such as ls /proc >> /tmp/proc or a command to execute a custom script. Environment assignment lines can have the following format: VAR=VALUE Any spaces around VAR are removed. No spaces around VALUE are allowed (unless you want them to be part of the value). The specified assignment takes effect from the next line until the end of the file, or to the next assignment of the same variable. The START_HOURS_RANGE variable defines an interval (in hours) when scheduled jobs can be run. In case this time interval is missed, for example, due to a power down, then scheduled jobs are not executed that day. The RANDOM_DELAY variable denotes the maximum number of minutes that will be added to the delay in minutes variable which is specified for each job. A RANDOM_DELAY set to 12 would therefore add, randomly, between 0 and 12 minutes to the delay in minutes for each job in that particular anacrontab. When set to 0, no random delay is added. Empty lines are either blank lines, line containing white spaces only, or lines with white spaces followed by a '#' followed by an arbi- trary comment. You can continue a line onto the next line by adding a '' at the end of it. In case you want to disable Anacron, add the 0anacron cron job (which is a part of crontab(1)) into the /etc/cron.hourly/jobs.deny direc- tory. EXAMPLE
This example shows how to set up an Anacron job similar in functionality to /etc/crontab which starts all regular jobs between 6:00 and 8:00 only. A RANDOM_DELAY which can be 30 minutes at the most is specified. Jobs will run serialized in a queue where each job is started only after the previous one is finished. # environment variables SHELL=/bin/sh PATH=/sbin:/bin:/usr/sbin:/usr/bin MAILTO=root RANDOM_DELAY=30 # Anacron jobs will start between 6am and 8am. START_HOURS_RANGE=6-8 # delay will be 5 minutes + RANDOM_DELAY for cron.daily 1 5 cron.daily nice run-parts /etc/cron.daily 7 0 cron.weekly nice run-parts /etc/cron.weekly @monthly 0 cron.monthly nice run-parts /etc/cron.monthly SEE ALSO
anacron(8), crontab(1) The Anacron README file. AUTHOR
Itai Tzur <itzur@actcom.co.il> Currently maintained by Pascal Hakim <pasc@(debian.org|redellipse.net)>. For Fedora, maintained by Marcela Malaova <mmaslano@redhat.com>. cronie 2012-11-22 ANACRONTAB(5)

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queuedefs(4)							   File Formats 						      queuedefs(4)

NAME
queuedefs - queue description file for at, batch, and cron SYNOPSIS
/etc/cron.d/queuedefs DESCRIPTION
The queuedefs file describes the characteristics of the queues managed by cron(1M). Each non-comment line in this file describes one queue. The format of the lines are as follows: q.[njobj][nicen][nwaitw] The fields in this line are: q The name of the queue. a is the default queue for jobs started by at(1); b is the default queue for jobs started by batch (see at(1)); c is the default queue for jobs run from a crontab(1) file. njob The maximum number of jobs that can be run simultaneously in that queue; if more than njob jobs are ready to run, only the first njob jobs will be run, and the others will be run as jobs that are currently running terminate. The default value is 100. nice The nice(1) value to give to all jobs in that queue that are not run with a user ID of super-user. The default value is 2. nwait The number of seconds to wait before rescheduling a job that was deferred because more than njob jobs were running in that job's queue, or because the system-wide limit of jobs executing has been reached. The default value is 60. Lines beginning with # are comments, and are ignored. EXAMPLES
Example 1: A sample file. # # a.4j1n b.2j2n90w This file specifies that the a queue, for at jobs, can have up to 4 jobs running simultaneously; those jobs will be run with a nice value of 1. As no nwait value was given, if a job cannot be run because too many other jobs are running cron will wait 60 seconds before trying again to run it. The b queue, for batch(1) jobs, can have up to 2 jobs running simultaneously; those jobs will be run with a nice(1) value of 2. If a job cannot be run because too many other jobs are running, cron(1M) will wait 90 seconds before trying again to run it. All other queues can have up to 100 jobs running simultaneously; they will be run with a nice value of 2, and if a job cannot be run because too many other jobs are running cron will wait 60 seconds before trying again to run it. FILES
/etc/cron.d/queuedefs queue description file for at, batch, and cron. SEE ALSO
at(1), crontab(1), nice(1), cron(1M) SunOS 5.10 1 Mar 1994 queuedefs(4)

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