Poise-Monit Cookbook

A Chef cookbook to manage Monit.

To install Monit and configure a mail server:

include_recipe 'poise-monit'

monit_config 'mailconfig' do
  content <<-EOH
SET MAILSERVER mail.example.com
SET ALERT devoops@example.com
EOH
end

To create a service managed by Monit with a health check:

poise_service 'apache2' do
  command '/usr/sbin/apache2 -f /etc/apache2/apache2.conf -DFOREGROUND'
  stop_signal 'WINCH'
  reload_signal 'USR1'
  provider :monit
  options :monit, checks: 'if failed host localhost port 80 protocol HTTP request "/" then restart'
end

• poise-monit::default – Install Monit.

• node['poise-monit']['default_recipe'] – Recipe used by the poise_service provider to install Monit if not already available. (default: poise-monit)
• node['poise-monit']['provider'] – Default provider for monit resource instances. (default: auto)
• node['poise-monit']['recipe'][*] – All subkeys of 'recipe' will be passed as properties to the monit resource before installation.

For example, the poise-monit recipe can be customized by setting:

override_attributes({
  'poise-monit' => {
    'recipe' => {
      'daemon_interval' => 60,
      'event_slots' => 0,
    }
  }
})

The monit resource installs and configures Monit.

monit 'monit' do
  daemon_interval 60
  event_slots 1000
end

• :enable – Install, enable and start Monit. (default)
• :disable – Stop, disable, and uninstall Monit.
• :start – Start Monit.
• :stop – Stop Monit.
• :restart – Stop and then start Monit.
• :reload – Send SIGHUP signal to Monit.

• service_name – Name of the Monit instance. (name attribute)
• daemon_interval – Number of seconds between service checks. (default: 120)
• daemon_delay – Number of intervals to wait on startup before running service checks. If unset or 0, no start delay is used. (default: nil)
• daemon_verbose – Run the daemon in verbose mode for debugging. (default: log_level==debug)
• event_slots – Number of slots in the Monit event buffer. Set to 0 to disable event buffering, or -1 for an unlimited queue. (default: 100)
• httpd_port – Port to listen on for Monit's HTTPD. If a path is specified, it is used as a Unix socket path. If set to nil or false, no HTTPD configuration is generated. This may break some other poise-monit resources. (default: /var/run/monit.sock if the version of Monit supports it, otherwise 2812)
• httpd_password – Cleartext password for authentication between the Monit daemon and CLI. Set to nil or false to disable authentication. (default: nil for Unix socket connections, otherwise auto-generated)
• httpd_username – Username for authentication between the Monit daemon and CLI. (default: cli)
• group – System group to deploy Monit as.
• logfile – Path to the Monit log file. (default: /var/log/monit.log)
• owner – System user to deploy Monit as.
• path – Path to the Monit configuration directory. (default: /etc/monit)
• pidfile – Path to the Monit PID file. (default: /var/run/monit.pid)
• var_path – Path the Monit state directory. (default: /var/lib/monit)
• version – Version of Monit to install.

The monit resource uses provide options for per-provider configuration. See the poise-service documentation for more information on using provider options.

The monit_config resource writes out a Monit configuration file to the conf.d/ directory.

monit_config 'ssh' do
  source 'monit_ssh.conf.erb'
  variables threshold: 5
end

• :create – Create and manage the configuration file. (default)
• :delete – Delete the configuration file.

• config_name – Name of the configuration file. (name attribute)
• content – File content to write.
• cookbook – Cookbook to search for source in.
• parent – Name or reference for the parent monit resource. (required, default: automatic)
• path – Path to the configuration file. (default: automatic)
• source – Template path to render.
• variables – Template variables.

One of source or content is required.

The monit_check resource writes out a Monit configuration file for a service check. It is a subclass of monit_config and so inherits its actions and properties. It defaults to being a process check.

monit_check 'httpd' do
  check 'if failed port 80 protocol http request "/_status" then restart'
  extra [
    'every 5 cycles',
    'group www',
  ]
end

• :create – Create and manage the configuration file. (default)
• :delete – Delete the configuration file.

• check_type – Type of check. (default: process)
• with – WITH-ish string for this check. This is the part that goes after the check name. Set to false to disable. (default: PIDFILE /var/run/check_name.pid)
• start_program – Command to use to start the service for process checks. Set to false disable. (default: automatic)
• stop_program – Command to use to stop the service for process checks. Set to false disable. (default: automatic)
• check – Service health check or checks. 'IF ' will be prepended if not given.
• extra – Line or lines to be added to the service definition as is.

The binaries_bitbucket provider supports installing Monit from static binaries mirrored to BitBucket. This is the default provider if you are installing on an OS that has binaries available.

monit 'monit' do
  provider :binaries
end

NOTE: If BitBucket is unavailable you can set the url provider option to https://mmonit.com/monit/dist/binary/%{version}/monit-%{version}-%{machine_label}.tar.gz to use downloads directly from mmonit.com, however this server has a relatively strict download quota system so this is not recommended.

• path – Path to install Monit to. (default: /opt/monit-)
• retries – Number of times to retry failed downloads. (default: 5)
• static_version – Full version number for use in interpolation. (default: automatic)
• strip_components – Value to pass to tar --strip-components. (default: 1)
• url – URL template to download from. (default: https://bitbucket.org/tildeslash/monit/downloads/monit-%{version}-%{machine_label}.tar.gz)

The system provider supports installing Monit from system packages. This requires EPEL for RHEL/CentOS as they do not ship Monit in the base OS repositories. Because this is not a default provider, EPEL is not a dependency of this cookbook, you will have to add it to your run list or as a dependency of a wrapper cookbook.

monit 'monit' do
  provider :system
end

• no_epel – Do not try to enable EPEL on EL nodes. (default: false)
• package – Package name to install. (default: monit)

The dummy provider supports using the monit resource with ChefSpec or other testing frameworks to not actually install Monit. It is used by default under ChefSpec.

monit 'monit' do
  provider :dummy
end

• monit_binary – Path to the monit executable. (default: /usr/bin/monit)

The monit service provider is included to allow poise_service resources to use Monit as the service manager. This uses the normal sysvinit provider from poise-service to generate the init scripts, but manages service state through Monit.

poise_service 'apache2' do
  command '/usr/sbin/apache2 -f /etc/apache2/apache2.conf -DFOREGROUND'
  stop_signal 'WINCH'
  reload_signal 'USR1'
  provider :monit
  options :monit, checks: 'if failed host localhost port 80 protocol HTTP request "/" then restart'
end

To set the monit provider as the global default, use poise-sevice-monit.

The service provider has two node attributes that can used for global tuning:

• node['poise-monit']['monit_service_timeout'] – Seconds before timeout when registering a new service with Monit. (default: 20)
• node['poise-monit']['monit_service_wait'] – Seconds to wait between attempts when registering a new service with Monit. (default: 1)

• pid_file – Path to PID file that the service command will create.
• pid_file_external – If true, assume the service will create the PID file itself. (default: true if pid_file option is set)
• template – Override the default script template. If you want to use a template in a different cookbook use 'cookbook:template'.
• monit_template – Override the default monit template. If you want to use a template in a different cookbook use 'cookbook:template'.
• command – Override the service command.
• directory – Override the service directory.
• environment – Override the service environment variables.
• reload_signal – Override the service reload signal.
• stop_signal – Override the service stop signal.
• user – Override the service user.
• never_restart – Never try to restart the service.
• never_reload – Never try to reload the service.
• script_path – Override the path to the generated service script.
• parent – Override the auto-detection of which monit resource to use.

Upgrading from the older monit cookbook is relatively straightforward. The node['monit'] attributes can either be converted to node['poise-monit']['recipe'] if you want to use the default recipe, or you can invoke the monit resource in your own recipe code if needed.

When switching cookbooks in-place on a server, make sure you check for any conf.d/ config files created by the old cookbook. Notably conf.d/compat.conf may interfere with the configuration generation. You can remove it:

monit_config 'compat' do
  action :delete
end

Development sponsored by Bloomberg.

The Poise test server infrastructure is sponsored by Rackspace.

Copyright 2015-2017, Noah Kantrowitz

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.