Cron declarations require a number of parameters. The following are the parameters used by Salt to define the various timing values for a cron job:
minute
hour
daymonth
month
dayweek
(0 to 6 are Sunday through Saturday, 7 can also be used for
Sunday)Warning
Any timing arguments not specified take a value of *
. This means that
setting hour
to 5
, while not defining the minute
param, will
result in Salt adding a job that will execute every minute between 5 and 6
A.M.!
Additionally, the default user for these states is root
. Therefore, if
the cron job is for another user, it is necessary to specify that user with
the user
parameter.
A long time ago (before 2014.2), when making changes to an existing cron job, the name declaration is the parameter used to uniquely identify the job, so if an existing cron that looks like this:
date > /tmp/crontest:
cron.present:
- user: root
- minute: 5
Is changed to this:
date > /tmp/crontest:
cron.present:
- user: root
- minute: 7
- hour: 2
Then the existing cron will be updated, but if the cron command is changed, then a new cron job will be added to the user's crontab.
The current behavior is still relying on that mechanism, but you can also specify an identifier to identify your crontabs:
date > /tmp/crontest:
cron.present:
- identifier: SUPERCRON
- user: root
- minute: 7
- hour: 2
New in version 2014.1.2.
And, some months later, you modify it:
superscript > /tmp/crontest:
cron.present:
- identifier: SUPERCRON
- user: root
- minute: 3
- hour: 4
New in version 2014.1.2.
The old date > /tmp/crontest will be replaced by superscript > /tmp/crontest.
Additionally, Salt also supports running a cron every x minutes
very similarly to the Unix
convention of using */5
to have a job run every five minutes. In Salt, this
looks like:
date > /tmp/crontest:
cron.present:
- user: root
- minute: '*/5'
The job will now run every 5 minutes.
Additionally, the temporal parameters (minute, hour, etc.) can be randomized by
using random
instead of using a specific value. For example, by using the
random
keyword in the minute
parameter of a cron state, the same cron
job can be pushed to hundreds or thousands of hosts, and they would each use a
randomly-generated minute. This can be helpful when the cron job accesses a
network resource, and it is not desirable for all hosts to run the job
concurrently.
/path/to/cron/script:
cron.present:
- user: root
- minute: random
- hour: 2
New in version 0.16.0.
Since Salt assumes a value of *
for unspecified temporal parameters, adding
a parameter to the state and setting it to random
will change that value
from *
to a randomized numeric value. However, if that field in the cron
entry on the minion already contains a numeric value, then using the random
keyword will not modify it.
Added the opportunity to set a job with a special keyword like '@reboot' or '@hourly'. Quotes must be used, otherwise PyYAML will strip the '@' sign.
/path/to/cron/script:
cron.present:
- user: root
- special: '@hourly'
The script will be executed every reboot if cron daemon support this option.
/path/to/cron/otherscript:
cron.absent:
- user: root
- special: '@daily'
This counter part definition will ensure than a job with a special keyword is not set.
salt.states.cron.
absent
(name, user='root', identifier=False, special=None, **kwargs)¶Verifies that the specified cron job is absent for the specified user; only the name is matched when removing a cron job.
salt.states.cron.
env_absent
(name, user='root')¶Verifies that the specified environment variable is absent from the crontab for the specified user
salt.states.cron.
env_present
(name, value=None, user='root')¶Verifies that the specified environment variable is present in the crontab for the specified user.
salt.states.cron.
file
(name, source_hash='', source_hash_name=None, user='root', template=None, context=None, replace=True, defaults=None, backup='', **kwargs)¶Provides file.managed-like functionality (templating, etc.) for a pre-made crontab file, to be assigned to a given user.
The source file to be used as the crontab. This source file can be
hosted on either the salt master server, or on an HTTP or FTP server.
For files hosted on the salt file server, if the file is located on
the master in the directory named spam, and is called eggs, the source
string is salt://spam/eggs
If the file is hosted on a HTTP or FTP server then the source_hash argument is also required
md5=e138491e9d5b97023cea823fe17bac22
When source_hash
refers to a hash file, Salt will try to find the
correct hash by matching the filename/URI associated with that hash. By
default, Salt will look for the filename being managed. When managing a
file at path /tmp/foo.txt
, then the following line in a hash file
would match:
acbd18db4cc2f85cedef654fccc4a4d8 foo.txt
However, sometimes a hash file will include multiple similar paths:
37b51d194a7513e45b56f6524f2d51f2 ./dir1/foo.txt
acbd18db4cc2f85cedef654fccc4a4d8 ./dir2/foo.txt
73feffa4b7f6bb68e44cf984c85f6e88 ./dir3/foo.txt
In cases like this, Salt may match the incorrect hash. This argument can be used to tell Salt which filename to match, to ensure that the correct hash is identified. For example:
foo_crontab:
cron.file:
- name: https://mydomain.tld/dir2/foo.txt
- source_hash: https://mydomain.tld/hashes
- source_hash_name: ./dir2/foo.txt
Note
This argument must contain the full filename entry from the
checksum file, as this argument is meant to disambiguate matches
for multiple files that have the same basename. So, in the
example above, simply using foo.txt
would not match.
New in version 2016.3.5.
salt.states.cron.
present
(name, user='root', minute='*', hour='*', daymonth='*', month='*', dayweek='*', comment=None, commented=False, identifier=False, special=None)¶Verifies that the specified cron job is present for the specified user.
For more advanced information about what exactly can be set in the cron
timing parameters, check your cron system's documentation. Most Unix-like
systems' cron documentation can be found via the crontab man page:
man 5 crontab
.
*
*
*
*
*
The cron job is set commented (prefixed with #DISABLED#
).
Defaults to False.
New in version 2016.3.0.
A special keyword to specify periodicity (eg. @reboot, @hourly...). Quotes must be used, otherwise PyYAML will strip the '@' sign.
New in version 2016.3.0.