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Tue May 14 08:50:19 2013 UTC (11 years, 4 months ago) by niro
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Tue May 14 08:50:19 2013 UTC (11 years, 4 months ago) by niro
File size: 2316 byte(s)
-added cronie
1 | niro | 2172 | .TH CRONTABS 4 2012-08-29 "Marcela Mašláňová" "Crontabs users' Manual" |
2 | .SH NAME | ||
3 | crontabs \- configuration and scripts for running periodical jobs | ||
4 | .SH SYNOPSIS | ||
5 | .B run-parts | ||
6 | .RB [ --list | --test ] \fP\fI<directory>\fP | ||
7 | .br | ||
8 | .SH DESCRIPTION | ||
9 | Crontabs is a historical name for the run-parts script and the system | ||
10 | crontab. The run-parts script runs all executables in the specified | ||
11 | directory. | ||
12 | .B Run-parts | ||
13 | runs all executables in the specified directory. | ||
14 | The execution of files can be allowed or denied by creating file | ||
15 | .B jobs.allow | ||
16 | or | ||
17 | .B jobs.deny | ||
18 | which worked similar as other allow/deny config files. The file must be | ||
19 | created in the specified directory. | ||
20 | .TP | ||
21 | .B --list | ||
22 | print names of all files (not limited to executables), but don't run | ||
23 | them. This option can't be used with | ||
24 | .B test | ||
25 | option. | ||
26 | .TP | ||
27 | .B --test | ||
28 | print names of files, which would be run. | ||
29 | |||
30 | Randomization of jobs can be configured in the | ||
31 | .IR /etc/sysconfig/run-parts | ||
32 | file. To enable randomization of jobs, set the RANDOMIZE parameter to 1 | ||
33 | and set the RANDOM parameter to an integer which determines a random | ||
34 | seed. Additionally, you may configure the RANDOMTIME parameter (again, | ||
35 | by specifying an integer) to provide an additional level of | ||
36 | randomization. Jobs are not randomized when the RANDOM and RANDOMTIME | ||
37 | parameters are set to 0. Values in these two parameters must be set to | ||
38 | 1 or larger to provide a good enough randomization. | ||
39 | |||
40 | Randomization of cron jobs can be useful for shared networks, where | ||
41 | multiple cron jobs executed at once can cause spikes in traffic, | ||
42 | especially during daily jobs. With randomized jobs, the workload is | ||
43 | evenly distributed throughout the day. | ||
44 | |||
45 | .SH EXAMPLE OF CONFIGURATION FILE | ||
46 | .nf | ||
47 | RANDOMIZE=1 | ||
48 | RANDOM=4 | ||
49 | RANDOMTIME=8 | ||
50 | .fi | ||
51 | .PP | ||
52 | Historically the crontab file contained configuration which called | ||
53 | .B run-parts | ||
54 | on files in | ||
55 | .I cron.{daily,weekly,monthly} | ||
56 | directories. These jobs are now run | ||
57 | indirectly through | ||
58 | .B anacron | ||
59 | to prevent conflicts between | ||
60 | .B cron | ||
61 | and | ||
62 | .B anacron. | ||
63 | That means the | ||
64 | .B anacron | ||
65 | package has to be installed if the jobs in these | ||
66 | directories should be running. Refer to the | ||
67 | .B anacron(8) | ||
68 | how to limit the time of day of the job execution. | ||
69 | |||
70 | .SH EXAMPLE | ||
71 | .I /etc/cron.daily/jobs.deny | ||
72 | could contain for example | ||
73 | .B 0logwatch | ||
74 | which forbid execution of this script. | ||
75 | .SH "SEE ALSO" | ||
76 | .B anacron(8), crontab(5) |