Description

Installs and configures Nagios server and NRPE client. Chef nodes are automatically discovered using search, and Nagios host groups are created based on Chef roles and optionally environments as well. NRPE client commands can be defined by using a LWRP, and Nagios service checks applied to hostgroups using definitions in data bag items.

Requirements

Chef

Chef version 0.10.10+ and Ohai 0.6.12+ are required.

Because of the heavy use of search, this recipe will not work with Chef Solo, as it cannot do any searches without a server.

This cookbook relies heavily on multiple data bags. See Data Bag below.

The system running the 'server' recipe should have a role named 'monitoring' so that NRPE clients can authorize monitoring from that system. This role name is configurable via an attribute. See Attributes below.

Platform

Debian 6
Ubuntu 10.04, 12.04
Red Hat Enterprise Linux (CentOS/Amazon/Scientific/Oracle) 5.8, 6.3

Notes: This cookbook has been tested on the listed platforms. It may work on other platforms with or without modification.

Cookbooks

apache2
build-essential
nginx
nginx_simplecgi
php
yum

Attributes

default

The following attributes are used by both client and server recipes.

node['nagios']['user'] - Nagios user, default 'nagios'.
node['nagios']['group'] - Nagios group, default 'nagios'.
node['nagios']['plugin_dir'] - location where Nagios plugins go, default '/usr/lib/nagios/plugins'.
node['nagios']['multi_environment_monitoring'] - Chef server will monitor hosts in all environments, not just its own, default 'false'

client

The following attributes are used for the NRPE client

node['nagios']['client']['install_method'] - whether to install from package or source. Default chosen by platform based on known packages available for NRPE: debian/ubuntu 'package', redhat/centos/fedora/scientific: source
node['nagios']['plugins']['url'] - url to retrieve the plugins source
node['nagios']['plugins']['version'] - version of the plugins source to download
node['nagios']['plugins']['checksum'] - checksum of the plugins source tarball
node['nagios']['nrpe']['home'] - home directory of nrpe, default /usr/lib/nagios
node['nagios']['nrpe']['conf_dir'] - location of the nrpe configuration, default /etc/nagios
node['nagios']['nrpe']['url'] - url to retrieve NRPE source
node['nagios']['nrpe']['version'] - version of NRPE source to download
node['nagios']['nrpe']['checksum'] - checksum of the nrpe source tarball
node['nagios']['nrpe']['packages'] - nrpe / plugin packages to install. The default attribute for RHEL/Fedora platforms contains a bare minimum set of packages. The full list of available packages is available at: http://dl.fedoraproject.org/pub/epel/6/x86_64/repoview/letter_n.group.html
node['nagios']['server_role'] - the role that the Nagios server will have in its run list that the clients can search for.

server

The following attributes are used for the Nagios server

node['nagios']['server']['install_method'] - whether to install from package or source. Default chosen by platform based on known packages available for Nagios: debian/ubuntu 'package', redhat/centos/fedora/scientific: source
node['nagios']['server']['service_name'] - name of the service used for Nagios, default chosen by platform, debian/ubuntu "nagios3", redhat family "nagios", all others, "nagios"
node['nagios']['home'] - Nagios main home directory, default "/usr/lib/nagios3"
node['nagios']['conf_dir'] - location where main Nagios config lives, default "/etc/nagios3"
node['nagios']['config_dir'] - location where included configuration files live, default "/etc/nagios3/conf.d"
node['nagios']['log_dir'] - location of Nagios logs, default "/var/log/nagios3"
node['nagios']['cache_dir'] - location of cached data, default "/var/cache/nagios3"
node['nagios']['state_dir'] - Nagios runtime state information, default "/var/lib/nagios3"
node['nagios']['run_dir'] - where pidfiles are stored, default "/var/run/nagios3"
node['nagios']['docroot'] - Nagios webui docroot, default "/usr/share/nagios3/htdocs"
node['nagios']['enable_ssl] - boolean for whether Nagios web server should be https, default false
node['nagios']['http_port'] - port that the Apache server should listen on, determined whether ssl is enabled (443 if so, otherwise 80)
node['nagios']['server_name'] - common name to use in a server cert, default "nagios"
node['nagios']['ssl_req'] - info to use in a cert, default /C=US/ST=Several/L=Locality/O=Example/OU=Operations/CN=#{node['nagios']['server_name']}/emailAddress=ops@#{node['nagios']['server_name']}
node['nagios']['server']['url'] - url to download the server source from if installing from source
node['nagios']['server']['version'] - version of the server source to download
node['nagios']['server']['checksum'] - checksum of the source files
node['nagios']['url'] - URL to host nagios from - defaults to nil and instead uses FQDN
node['nagios']['notifications_enabled'] - set to 1 to enable notification.
node['nagios']['check_external_commands']
node['nagios']['default_contact_groups']
node['nagios']['sysadmin_email'] - default notification email.
node['nagios']['sysadmin_sms_email'] - default notification sms.
node['nagios']['server_auth_method'] - authentication with the server can be done with openid (using apache2::mod_auth_openid), cas (using apache2::mod_auth_cas),ldap (using apache2::mod_authnz_ldap), or htauth (basic). The default is openid, "cas" will utilize cas authentication, "ldap" will utilize LDAP authentication, and any other value will use htauth (basic).
node['nagios']['cas_login_url'] - login url for cas if using cas authentication.
node['nagios']['cas_validate_url'] - validation url for cas if using cas authentication.
node['nagios']['cas_validate_server'] - whether to validate the server cert. Defaults to off.
node['nagios']['cas_root_proxy_url'] - if set, sets the url that the cas server redirects to after auth.
node['nagios']['ldap_bind_dn'] - DN used to bind to the server when searching for ldap entries.
node['nagios']['ldap_bind_password'] - bind password used with the DN provided for searcing ldap.
node['nagios']['ldap_url'] - ldap url and search parameters.
node['nagios']['ldap_authoritative'] - accepts "on" or "off". controls other authentication modules from authenticating the user if this one fails.
node['nagios']['users_databag_group'] - users databag group considered Nagios admins. defaults to sysadmins
node['nagios']['host_name_attribute'] - node attribute to use for naming the host. Must be unique across monitored nodes. Defaults to hostname
node['nagios']['templates']
node['nagios']['interval_length'] - minimum interval.
node['nagios']['default_host']['check_interval']
node['nagios']['default_host']['retry_interval']
node['nagios']['default_host']['max_check_attempts']
node['nagios']['default_host']['notification_interval']
node['nagios']['default_service']['check_interval']
node['nagios']['default_service']['retry_interval']
node['nagios']['default_service']['max_check_attempts']
node['nagios']['default_service']['notification_interval']
node['nagios']['server']['web_server'] - web server to use. supports Apache or Nginx, default "apache"
node['nagios']['server']['nginx_dispatch'] - nginx dispatch method. support cgi or php, default "cgi"
node['nagios']['server']['stop_apache'] - stop apache service if using nginx, default false
node['nagios']['server']['redirect_root'] - if using Apache, should http://server/ redirect to http://server/nagios3 automatically, default false
node['nagios']['server']['normalize_hostname'] - If set to true, normalize all hostnames in hosts.cfg to lowercase. Defaults to false.

Recipes

default

Includes the nagios::client recipe to install NRPE client.

client

Includes the correct NRPE client installation recipe based on platform, either nagios::client_package or nagios::client_source.

The client recipe searches for servers allowed to connect via NRPE that have a role named in the node['nagios']['server_role'] attribute. The recipe will also install the required packages and start the NRPE service. A custom plugin for checking memory is also added.

Searches are confined to the node's chef_environment unless the multi_environment_monitoring attribute has been set to true.

Client commands for NRPE can be installed using the nrpecheck lwrp. (See Resources/Providers below.)

RHEL and Fedora default to installation via source, but you can install NRPE via package by changing node['nagios']['client']['install_method'] to "package". Note that this will enable the EPEL repository on RHEL systems, which may not be desired. You will also need to modify node['nagios']['nrpe']['packages'] to include the appropriate NRPE plugins for your environment. The complete list is available at http://dl.fedoraproject.org/pub/epel/6/x86_64/repoview/letter_n.group.html

client_package

Installs the NRPE client and plugins from packages. Default for Debian / Ubuntu systems.

client_source

Installs the NRPE client and plugins from source. Default for Redhat and Fedora based systems, as native packages for NRPE are not available in the default repositories.

server

Includes the correct client installation recipe based on platform, either nagios::server_package or nagios::server_source.

The server recipe sets up Apache as the web front end by default. The nagios::client recipe is also included. This recipe also does a number of searches to dynamically build the hostgroups to monitor, hosts that belong to them and admins to notify of events/alerts.

Searches are confined to the node's chef_environment unless multi-environment monitoring is enabled.

The recipe does the following:

Searches for users in 'users' databag belonging to to 'sysadmins' group and authorizes them to access the Nagios web UI and receive notification e-mails.
Searches all available roles/environments and builds a list which will become the Nagios hostgroups.
Places nodes in Nagios hostgroups by role / environment membership.
Installs various packages required for the server.
Sets up configuration directories.
Moves the package-installed Nagios configuration to a 'dist' directory.
Disables the 000-default VirtualHost present on Debian/Ubuntu Apache2 package installations.
Templates configuration files for services, contacts, contact groups, templates, hostgroups and hosts.
Enables the Nagios web UI.
Starts the Nagios server service

server_package

Installs the Nagios server from packages. Default for Debian / Ubuntu systems.

server_source

Installs the Nagios server from source. Default for Red Hat / Fedora based systems as native packages for Nagios are not available in the default repositories.

pagerduty

Installs and configures pagerduty plugin for nagios. You need to set a node['nagios']['pagerduty_key'] attribute on your server for this to work. This can be set through environments so that you can use different API keys for servers in production vs staging for instance.

This recipe was written based on the Nagios Integration Guide from PagerDuty which explains how to get an API key for your nagios server.

Data Bags

Users

Create a users data bag that will contain the users that will be able to log into the Nagios webui. Each user can use htauth with a specified password, or an openid. Users that should be able to log in should be in the sysadmin group. Example user data bag item:

{
  "id": "nagiosadmin",
  "groups": "sysadmin",
  "htpasswd": "hashed_htpassword",
  "openid": "http://nagiosadmin.myopenid.com/",
  "nagios": {
    "pager": "nagiosadmin_pager@example.com",
    "email": "nagiosadmin@example.com"
  }
}

When using server_auth_method 'openid' (default), use the openid in the data bag item. Any other value for this attribute (e.g., "htauth", "htpasswd", etc) will use the htpasswd value as the password in /etc/nagios3/htpasswd.users.

The openid must have the http:// and trailing /. The htpasswd must be the hashed value. Get this value with htpasswd:

% htpasswd -n -s nagiosadmin
New password:
Re-type new password:
nagiosadmin:{SHA}oCagzV4lMZyS7jl2Z0WlmLxEkt4=

For example use the {SHA}oCagzV4lMZyS7jl2Z0WlmLxEkt4= value in the data bag.

Contacts and Contact Groups

To send alerting notification to contacts that aren't authorized to login to Nagios via the 'users' data bag create nagios_contacts and nagios_contactgroups data bags.

Example nagios_contacts data bag item

{
  "id": "devs",
  "alias": "Developers",
  "use": "default-contact",
  "email": "devs@company.com",
  "pager": "page_the_devs@company.com"
}

Example nagios_contactgroup data bag item

{
  "id": "non_admins",
  "alias": "Non-Administrator Contacts",
  "members": "devs helpdesk managers"
}

Services

To add service checks to Nagios create a nagios_services data bag containing definitions for services to be monitored. This allows you to add monitoring rules without directly editing the services and commands templates in the cookbook. Each service will be named based on the id of the data bag item and the command will be named using the same id prepended with "check_". Just make sure the id in your data bag doesn't conflict with a service or command already defined in the templates.

Here's an example of a service check for sshd that you could apply to all hostgroups:

{
  "id": "ssh",
  "hostgroup_name": "linux",
  "command_line": "$USER1$/check_ssh $HOSTADDRESS$"
}

You may optionally define the service template for your service by including service_template and a valid template name. Example: "service_template": "special_service_template". You may also optionally add a service description that will be displayed in the Nagios UI using "description": "My Service Name". If this is not present the databag item ID will be used as the description. You use defined escalations for the service with 'use_escalation'. See _Service_Escalations for more information.

You may also use an already defined command definition by omitting the command_line parameter and using use_existing_command parameter instead:

{
"id": "pingme",
 "hostgroup_name": "all",
 "use_existing_command": "check-host-alive"
}

Service Groups

Create a nagios_servicegroups data bag that will contain definitions for service groups. Each server group will be named based on the id of the data bag.

{
"id": "ops",
"alias": "Ops",
"notes": "Services for ops"
}

You can group your services by using the "servicegroups" keyword in your services data bags. For example, to have your ssh checks show up under the ops service group, you could define it like this:

{
"id": "ssh",
"hostgroup_name": "all",
"command_line": "$USER1$/check_ssh $HOSTADDRESS$",
"servicegroups": "ops"
}

Templates

Templates are optional, but allow you to specify combinations of attributes to apply to a service. Create a nagios_templates\ data bag that will contain definitions for templates to be used. Each template need only specify id and whichever parameters you want to override.

Here's an example of a template that reduces the check frequency to once per day and changes the retry interval to 1 hour.

{
  "id": "dailychecks",
  "check_interval": "86400",
  "retry": "3600"
}

You then use the template in your service data bag as follows:

{
  "id": "expensive_service_check",
  "hostgroup_name": "linux",
  "command_line": "$USER1$/check_example $HOSTADDRESS$",
  "service_template": "dailychecks"
}

Search Defined Hostgroups

Create a nagios_hostgroups data bag that will contain definitions for Nagios hostgroups populated via search. These data bags include a Chef node search query that will populate the Nagios hostgroup with nodes based on the search.

Here's an example to find all HP hardware systems for an "hp_systems" hostgroup:

{
  "search_query": "dmi_system_manufacturer:HP",
  "hostgroup_name": "hp_systems",
  "id": "hp_systems"
}

Monitoring Systems Not In Chef

Create a nagios_unmanagedhosts data bag that will contain definitions for hosts not in Chef that you would like to manage. "hostgroups" can be an existing Chef role (every Chef role gets a Nagios hostgroup) or a new hostgroup. Note that "hostgroups" must be an array of hostgroups even if it contains just a single hostgroup.

Here's an example host definition:

{
  "address": "webserver1.mydmz.dmz",
  "hostgroups": ["web_servers","production_servers"],
  "id": "webserver1",
  "notifications": 1
}

Service Escalations

You can optionally define service escalations for the data bag defined services. Doing so involves two steps - creating the escalation data bag and invoking it from the service. For example, to create an escalation to page managers on a 15 minute period after the 3rd page:

{
  "name": "15-minute-escalation",
  "contact_groups": "managers",
  "first_notification": "3",
  "last_notification": "0",
  "escalation_period": "24x7",
  "notification_interval": "900"
}

Then, in the service data bag,

{
  "id": "my-service",
  ...
  "use_escalation": "15-minute-escalation"
}

Event Handlers

You can optionally define event handlers to trigger on service alerts by creating a nagios_eventhandlers data bag that will contain definitions of event handlers for services monitored via Nagios.

This example event handler data bags restarts chef-client. Note: This assumes you have already defined a NRPE job restart_chef-client on the host where this command will run. You can use the NRPE LWRP to add commands to your local NRPE configs from within your cookbooks.

{
  "command_line": "$USER1$/check_nrpe -H $HOSTADDRESS$ -t 45 -c restart_chef-client",
  "id": "restart_chef-client"
}

Once you've defined an event handler you will need to add the event handler to a service definition in order to trigger the action. See the example service definition below.

{
  "command_line": "$USER1$/check_nrpe -H $HOSTADDRESS$ -t 45 -c check_chef_client",
  "hostgroup_name": "linux",
  "id": "chef-client",
  "event_handler": "restart_chef-client"
}

Monitoring Role

Create a role to use for the monitoring server. The role name should match the value of the attribute "node['nagios']['server_role']". By default, this is 'monitoring'. For example:

% cat roles/monitoring.rb
name "monitoring"
description "Monitoring server"
run_list(
  "recipe[nagios::server]"
)

default_attributes(
  "nagios" => {
    "server_auth_method" => "htauth"
  }
)

% knife role from file monitoring.rb

Definitions

nagios_conf

This definition is used to drop in a configuration file in the base Nagios configuration directory's conf.d. This can be used for customized configurations for various services.

Libraries

default

The library included with the cookbook provides some helper methods used in templates.

nagios_boolean
nagios_interval - calculates interval based on interval length and a given number of seconds.
nagios_attr - retrieves a nagios attribute from the node.

Resources/Providers

nrpecheck

The nrpecheck LWRP provides an easy way to add and remove NRPE checks from within cookbooks.

Actions

:add creates a NRPE configuration file and restart the NRPE process. Default action.
:remove removes the configuration file and restart the NRPE process

Attribute Parameters

command_name The name of the check. This is the command that you will call from your nagios_service data bag check
warning_condition String that you will pass to the command with the -w flag
critical_condition String that you will pass to the command with the -c flag
command The actual command to execute (including the path). If this is not specified, this will use node['nagios']['plugin_dir']/command_name as the path to the command.
parameters Any additional parameters you wish to pass to the plugin.

Examples

# Use LWRP to define check_load
nagios_nrpecheck "check_load" do
  command "#{node['nagios']['plugin_dir']}/check_load"
  warning_condition node['nagios']['checks']['load']['warning']
  critical_condition node['nagios']['checks']['load']['critical']
  action :add
end

# Remove the check_load definition
nagios_nrpecheck "check_load" do
  action :remove
end

Usage

server setup

Create a role named 'monitoring', and add the nagios server recipe to the run_list. See Monitoring Role above for an example.

Apply the nagios client recipe to nodes in order to install the NRPE client

By default the Nagios server will only monitor systems in its same environment. To change this set the multi_environment_monitoring attribute. See Attributes

Create data bag items in the users data bag for each administer you would like to be able to login to the Nagios server UI. Pay special attention to the method you would like to use to authorization users (openid or htauth). See Users and Atttributes

At this point you now have a minimally functional Nagios server, however the server will lack any service checks outside of the single Nagios Server health check.

defining checks

NRPE commands are defined in recipes using the nrpecheck LWRP provider. For base system monitoring such as load, ssh, memory, etc you may want to create a cookbook in your environment that defines each monitoring command via the LWRP. See the examples folder for an example of base monitoring.

With NRPE commands created using the LWRP you will need to define nagios Services to use those commands. These services are defined using the nagios_services data bag and applied to roles and/or environments. See Services

enabling notifications

You need to set default['nagios']['notifications_enabled'] = 1 attribute on your nagios server to enable email notifications.

For email notifications to work an appropriate mail program package and local MTA need to be installed so that /usr/bin/mail or /bin/mail is available on the system.

Example:

Include postfix cookbook to be installed on your nagios server node.

Add override_attributes to your monitoring role:

% cat roles/monitoring.rb

name "monitoring"
description "Monitoring Server"
run_list(
  "recipe[nagios::server]",
  "recipe[postfix]"
)

override_attributes(
  "nagios" => { "notifications_enabled" => "1" },
  "postfix" => { "myhostname":"your_hostname", "mydomain":"example.com" }
)

default_attributes(
  "nagios" => { "server_auth_method" => "htauth" }
)

% knife role from file monitoring.rb

License and Author

Author:: Joshua Sierles joshua@37signals.com Author:: Nathan Haneysmith nathan@opscode.com Author:: Joshua Timberman joshua@opscode.com Author:: Seth Chisamore schisamo@opscode.com Author:: Tim Smith tsmith84@gmail.com

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.

pwelch/nagios

Description

Requirements

Chef

Platform

Cookbooks

Attributes

default

client

server

Recipes

default

client

client_package

client_source

server

server_package

server_source

pagerduty

Data Bags

Users

Contacts and Contact Groups

Services

Service Groups

Templates

Search Defined Hostgroups

Monitoring Systems Not In Chef

Service Escalations

Event Handlers

Monitoring Role

Definitions

nagios_conf

Libraries

default

Resources/Providers

nrpecheck

Actions

Attribute Parameters

Examples

Usage

server setup

defining checks

enabling notifications

License and Author