Get started managing an NTP service

Network Time Protocol (NTP) is one of the most crucial, yet easiest, services to configure and manage with Puppet, to properly synchronize time across all your nodes. Follow this guide to get started managing a NTP service using the Puppet ntp module.

1. The first step is installing the puppetlabs-ntp module. The puppetlabs-ntp module is part of the supported modules program; these modules are supported, tested, and maintained by Puppet. For more information on puppetlabs-ntp, see the README. To install it, run:

   puppet module install puppetlabs-ntp

   The resulting output is similar to this:

    Preparing to install into /etc/puppetlabs/puppet/modules ...
       Notice: Downloading from http://forgeapi.puppetlabs.com ...
       Notice: Installing -- do not interrupt ...
       /etc/puppetlabs/puppet/environments/production/modules
       └── puppetlabs-ntp (v3.1.2)

   That’s it! You’ve just installed the puppetlabs-ntp module.
2. The next step is adding classes from the NTP module to the main manifest.

   The NTP module contains several classes. Classes are named chunks of Puppet code and are the primary means by which Puppet configures nodes. The NTP module contains the following classes:

   • ntp: the main class, which includes all other NTP classes, including the classes in this list.

   • ntp::install: handles the installation packages.

   • ntp::config: handles the configuration file.

   • ntp::service: handles the service.

   You’re going to add the ntp class to the default node in your main manifest. Depending on your needs or infrastructure, you might have a different group that you’ll assign NTP to, but you would take similar steps.

   1. From the command line on the master, navigate to the directory that contains the main manifest: 

      cd /etc/puppetlabs/code/environments/production/manifests

   2. Use your text editor to open site.pp.
   3. Add the following Puppet code to site.pp:

      node default {
        class { 'ntp':
              servers => ['nist-time-server.eoni.com','nist1-lv.ustiming.org','ntp-nist.ldsbc.edu']
        }
      }
      

      Note: If your site.pp file already has a default node in it, add just the class and servers lines to it.

      Note: For additional time server options, see the list at https://www.ntppool.org/.
   4. On your agent, start a Puppet run:

      puppet agent -t

      Your Puppet-managed node is now configured to use NTP. 

3. To check if the NTP service is running, run:

   puppet resource service ntpd

   The result looks like this:

   service { 'ntpd':
     		  ensure => 'running',
    		  enable => 'true',
   	}

4. If you want to configure the NTP service to run differently on different nodes, you can set up NTP on nodes other than default in the site.pp file.

   In previous steps, you’ve been configuring the default node.

   In the example below, two NTP servers (kermit and grover) are configured to talk to outside time servers. The other NTP servers (snuffie, bigbird, and hooper) use those two primary servers to sync their time.

   One of the primary ntp servers, kermit, is very cautiously configured — it can’t afford outages, so it’s not allowed to automatically update its NTP server package without testing. The other servers are more permissively configured.

   The site.pp looks like this:

   node "kermit.example.com" {
     class { "ntp":
           servers    => [ '0.us.pool.ntp.org iburst','1.us.pool.ntp.org iburst','2.us.pool.ntp.org iburst','3.us.pool.ntp.org iburst'],
           autoupdate => false,
           restrict   => [],
           enable     => true,
     }
   }
   
   node "grover.example.com" {
     class { "ntp":
           servers    => [ 'kermit.example.com','0.us.pool.ntp.org iburst','1.us.pool.ntp.org iburst','2.us.pool.ntp.org iburst'],
           autoupdate => true,
           restrict   => [],
           enable     => true,
     }
   }
   
   node "snuffie.example.com", "bigbird.example.com", "hooper.example.com" {
     class { "ntp":
           servers    => [ 'grover.example.com', 'kermit.example.com'],
           autoupdate => true,
           enable     => true,
     }
   }

   In this way, it is possible to configure NTP on multiple nodes to suit your needs.