diff options
Diffstat (limited to 'system/anacron/README')
-rw-r--r-- | system/anacron/README | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/system/anacron/README b/system/anacron/README new file mode 100644 index 0000000000..733c963087 --- /dev/null +++ b/system/anacron/README @@ -0,0 +1,36 @@ +anacron (periodic command scheduler) + +anacron is a periodic command scheduler. It executes commands at +intervals specified in days. Unlike cron, it does not assume that the +system is running continuously. It can therefore be used to control +the execution of daily, weekly and monthly jobs (or anything with a +period of n days), on systems that don't run 24 hours a day. When +installed and configured properly, Anacron will make sure that the +commands are run at the specified intervals as closely as +machine-uptime permits. + +Every time Anacron is run, it reads a configuration file that +specifies the jobs Anacron controls, and their periods in days. If a +job wasn't executed in the last n days, where n is the period of that +job, Anacron executes it. Anacron then records the date in a special +timestamp file that it keeps for each job, so it can know when to run +it again. When all the executed commands terminate, Anacron exits. + +It is recommended to run Anacron from the system boot-scripts. For +example, add the following lines to /etc/rc.d/rc.local: + + if [ -x /usr/sbin/anacron -a -f /etc/anacrontab ]; then + /usr/sbin/anacron -s > /dev/null 2>&1 + fi + +This way the jobs "whose time has come" will be run shortly after the +machine boots. A delay can be specified for each job so that the +machine isn't overloaded at boot time. + +In addition to running Anacron from the boot-scripts, it is also +recommended to schedule it as a daily cron-job (usually at an early +morning hour), so that if the machine is kept running for a night, +jobs for the next day will still be executed. + +See anacron (8), anacrontab (5) and /usr/doc/anacron-2.3/README +for further information. |