salt.states.cron¶

Management of cron, the Unix command scheduler¶

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)

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

And, some months later, you modify it:

superscript > /tmp/crontest:
  cron.present:
    - identifier: SUPERCRON
    - user: root
    - minute: 3
    - hour: 4

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

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.

salt.states.cron.absent(name, user='root', identifier=False, **kwargs)¶

Verifies that the specified cron job is absent for the specified user; only the name is matched when removing a cron job.

name

The command that should be absent in the user crontab.

user

The name of the user whose crontab needs to be modified, defaults to the root user

identifier

Custom-defined identifier for tracking the cron line for future crontab edits. This defaults to the state id

salt.states.cron.env_absent(name, user='root')¶

Verifies that the specified environment variable is absent from the crontab for the specified user

name

The name of the environment variable to remove from the user crontab

user

The name of the user whose crontab needs to be modified, defaults to the root 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.

name

The name of the environment variable to set in the user crontab

user

The name of the user whose crontab needs to be modified, defaults to the root user

value

The value to set for the given environment variable

salt.states.cron.file(name, source_hash='', user='root', template=None, context=None, replace=True, defaults=None, env=None, backup='', **kwargs)¶

Provides file.managed-like functionality (templating, etc.) for a pre-made crontab file, to be assigned to a given user.

name

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

source_hash

This can be either a file which contains a source hash string for the source, or a source hash string. The source hash string is the hash algorithm followed by the hash of the file: md5=e138491e9d5b97023cea823fe17bac22

user

The user to whom the crontab should be assigned. This defaults to root.

template

If this setting is applied then the named templating engine will be used to render the downloaded file. Currently, jinja and mako are supported.

context

Overrides default context variables passed to the template.

replace

If the crontab should be replaced, if False then this command will be ignored if a crontab exists for the specified user. Default is True.

defaults

Default context passed to the template.

backup

Overrides the default backup mode for the user's crontab.

salt.states.cron.present(name, user='root', minute='*', hour='*', daymonth='*', month='*', dayweek='*', comment=None, identifier=False)¶

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.

name

The command that should be executed by the cron job.

user

The name of the user whose crontab needs to be modified, defaults to the root user

minute

The information to be set into the minute section, this can be any string supported by your cron system's the minute field. Default is *

hour

The information to be set in the hour section. Default is *

daymonth

The information to be set in the day of month section. Default is *

month

The information to be set in the month section. Default is *

dayweek

The information to be set in the day of week section. Default is *

comment

User comment to be added on line previous the cron job

identifier

Custom-defined identifier for tracking the cron line for future crontab edits. This defaults to the state id