Home / server / Questions / 584972
Accepted
msanford
Asked: 2014-03-28 09:44:24 +0800 CST

Correct way to add commands to to rc.local above "exit 0" with puppet?

  • 772

A puppet novice, I'm currently working on a deployment script that will start a couple of foreverjs services from rc.local at boot time.

My concern is that, in Ubuntu, rc.local comes with an exit 0 at the bottom of the file.

I don't see a way of using stdlib's file_line directive to ensure that my lines appear above the exit command (or anywhere else in particular, should the need arise).

I can do it with an exec block and some ugly sed, but there must be a more standard, elegant way in puppet?

puppet

2 Answers

  1. Best Answer

    You can use the PuppetLabs Concat module to dynamically insert parts into the rc.local file, like so:

    Define the file as a concat file, and add a header (hash-bang, "managed by Puppet" comment, etc) - note the below may not work, I'm unsure of Puppet's newline handling off the top of my head!

    concat { '/etc/rc.local':
  ensure => present,
}

concat::fragment { '00_rc.local_header':
  target  => '/etc/rc.local'
  content => '#!/bin/bash\n# This file is manageed by Puppet, do not modify!',
  order   => '01'
}

    Add your custom parts, making sure to specify the correct target and an order value that is higher than your header:

    concat::fragment { '05_rc.local_custom':
  target  => '/etc/rc.local',
  content => template('path/to/template.erb'),
  order   => '05'
}

concat::fragment { '15_rc.local_custom_2':
  target  => '/etc/rc.local',
  source  => 'puppet:///modules/mymodule/myfile.txt',
  order   => '06'
}

    Add the exit 0 footer:

    concat::fragment { '99_rc.local_footer':
  target  => '/etc/rc.local',
  content => 'exit 0\n',
  order   => '99'
}

    Et fin!

    You can use concat::fragment across multiple subclasses (and also multiple modules, though this really isn't recommended!) as long as you set the correct target value and you have that file declared as a concat resource. The order parameter allows you to position elements within the file.

    Check the module's usage readme for more.

    • 5

  2. If you have the cron service installed you can use it for this purpose by using the @reboot time specification. What makes this easier to manage with puppet is that you can just create a separate file in /etc/cron.d instead of trying to edit a single monolithic file.

    I tested that the following works:

    file { "/etc/cron.d/at_startup_myscript":
    content => "@reboot root /usr/local/bin/myscript.sh \n",
}
    • 1