Red Hat ENTERPRISE LINUX 5 - VIRTUAL SERVER ADMINISTRATION, Руководство по развертыванию

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Controlling Access to At and Batch
509
Option Description
-f
Read the commands or shell script from a file instead of specifying
them at the prompt.
-m
Send email to the user when the job has been completed.
-v
Display the time that the job is executed.
Table 35.1.
at
and
batch
Command Line Options
35.2.5. Controlling Access to At and Batch
The
/etc/at.allow
and
/etc/at.deny
files can be used to restrict access to the
at
and
batch
commands. The format of both access control files is one username on each line. Whitespace is not
permitted in either file. The
at
daemon (
atd
) does not have to be restarted if the access control files
are modified. The access control files are read each time a user tries to execute the
at
or
batch
commands.
The root user can always execute
at
and
batch
commands, regardless of the access control files.
If the file
at.allow
exists, only users listed in it are allowed to use
at
or
batch
, and the
at.deny
file is ignored.
If
at.allow
does not exist, users listed in
at.deny
are not allowed to use
at
or
batch
.
35.2.6. Starting and Stopping the Service
To start the
at
service, use the command
/sbin/service atd start
. To stop the service, use
the command
/sbin/service atd stop
. It is recommended that you start the service at boot
time. Refer to
Chapter 16, Controlling Access to Services
for details on starting the cron service
automatically at boot time.
35.3. Additional Resources
To learn more about configuring automated tasks, refer to the following resources.
35.3.1. Installed Documentation
•
cron
man page — overview of cron.
•
crontab
man pages in sections 1 and 5 — The man page in section 1 contains an overview of the
crontab
file. The man page in section 5 contains the format for the file and some example entries.
•
/usr/share/doc/at- <version> /timespec
contains more detailed information about the times
that can be specified for cron jobs.
•
at
man page — description of
at
and
batch
and their command line options.