Introduction

collectd-mongodb is a collectd plugin that collects statistics from a MongoDB server.

This plugin is a direct port of the MongoDB C plugin that will be part of collectd 5.1, it works with Collectd 4.9.x and 4.10.x.

Requirements

• Collectd 4.9 or later (for the Python plugin)
• Python 2.4 or later
• MongoDB 2.6 or later
• PyMongo 3.x (To use SSL/TLS, install Pymongo with TLS support by running pip install pymongo[tls].)

Configuration

The plugin has some configuration options even though none are mandatory. This is done by passing parameters via the config section in your Collectd config. The following parameters are recognized:

• User - the username for authentication
• Password - the password for authentication
• Host - hostname or IP address of the mongodb server; defaults to 127.0.0.1
• Port - the port of the mongodb server; defaults to 27017
• Database - the databases you want to monitor defaults to "admin". You can provide more than one database. Note that the first database must be "admin", as it is used to perform a serverStatus()
• Interval - How frequently to send metrics in seconds | collectd Interval setting |
• SendCollectionMetrics - Whether to send collection level metrics or not; defaults to false.
• SendCollectionTopMetrics - Whether to send collection level top (timing) metrics or not; defaults to false.
• CollectionMetricsIntervalMultiplier - How frequently to send collection level metrics as a multiple of the configured plugin interval (e.g. if the Interval is 15 and the multiplier is 4, collection level metrics will be fetched every minute); defaults to 6.

SSL/TLS Configuration

To use SSL/TLS, install Pymongo with TLS support by running pip install pymongo[tls].

• UseTLS - set this to true if you want to connect to Mongo using TLS/x509/SSL.
• CACerts - path to a CA cert that will be used to verify the certificate that Mongo presents (not needed if not using TLS or if Mongo's cert is signed by a globally trusted issuer already installed in the default location on your OS)
• TLSClientCert - path to a client certificate (not needed unless your Mongo instance requires x509 client verification)
• User (required for TLS client auth) - The username associated with the client cert (this is the subject field of the client cert, formatted according to RFC2253 and in the same order that was specified when creating the user in the Mongo $external database). You can get this value by running the following command: openssl x509 -in <pathToClient PEM> -inform PEM -subject -nameopt RFC2253.
• TLSClientKey - path to a client certificate key (not needed unless your Mongo instance requires x509 client verification, or if your client cert above has the key included)
• TLSClientKeyPassphrase - passphrase for the TLSClientKey above (not needed if not using TLS Client auth, requires Python 2.7.9+)

The following is an example Collectd configuration for this plugin:

<LoadPlugin python>
    Globals true
</LoadPlugin>

<Plugin python>
    # mongodb.py is at path /opt/collectd-plugins/mongodb.py
    ModulePath "/opt/collectd-plugins/"

    Import "mongodb"
    <Module mongodb>
        Host "127.0.0.1"
        Port "27017"
        User ""
        Password "password"
        Database "admin" "db-prod" "db-dev"

        UseTLS true

        # If using TLS client auth with cert and key in same file without passphrase
        TLSClientCert "/path/to/cert.pem"
        User "CN=example.com,OU=Acme\,Inc,L=Springfield,C=US"
    </Module>
</Plugin>

The data-sets in types.db need to be added to the types.db file given by the collectd.conf TypesDB directive. See the types.db(5) man page for more information.

If you're monitoring a secured MongoDB deployment, declaring a user with minimal read-only roles is a good practice, such as :

db.createUser( {
  user: "collectd",
  pwd: "collectd",
  roles: [ { role: "readAnyDatabase", db: "admin" }, { role: "clusterMonitor", db: "admin" } ]
});