MongoDB

Plugin: go.d.plugin Module: mongodb

Overview

This collector monitors MongoDB servers.

Executed queries:

• serverStatus
• dbStats
• replSetGetStatus

This collector is supported on all platforms.

This collector supports collecting metrics from multiple instances of this integration, including remote instances.

Default Behavior

Auto-Detection

This integration doesn't support auto-detection.

Limits

The default configuration for this integration does not impose any limits on data collection.

Performance Impact

The default configuration for this integration is not expected to impose a significant performance impact on the system.

Setup

You can configure the mongodb collector in two ways:

:::important

UI configuration requires paid Netdata Cloud plan.

:::

Prerequisites

Create a read-only user

Create a read-only user for Netdata in the admin database.

• Authenticate as the admin user:

  bashCopy

  use admin
  db.auth("admin", "<MONGODB_ADMIN_PASSWORD>")
  

• Create a user:

  bashCopy

  db.createUser({
  "user":"netdata",
  "pwd": "<UNIQUE_PASSWORD>",
  "roles" : [
  {role: 'read', db: 'admin' },
  {role: 'clusterMonitor', db: 'admin'},
  {role: 'read', db: 'local' }
  ]
  })
  

Configuration

Options

The following options can be defined globally: update_every, autodetection_retry.

via UI

Configure the mongodb collector from the Netdata web interface:

1. Go to Nodes.
2. Select the node where you want the mongodb data-collection job to run and click the :gear: (Configure this node). That node will run the data collection.
3. The Collectors → Jobs view opens by default.
4. In the Search box, type mongodb (or scroll the list) to locate the mongodb collector.
5. Click the + next to the mongodb collector to add a new job.
6. Fill in the job fields, then click Test to verify the configuration and Submit to save.
   • Test runs the job with the provided settings and shows whether data can be collected.
   • If it fails, an error message appears with details (for example, connection refused, timeout, or command execution errors), so you can adjust and retest.

via File

The configuration file name for this integration is go.d/mongodb.conf.

The file format is YAML. Generally, the structure is:

update_every: 1
autodetection_retry: 0
jobs:
  - name: some_name1
  - name: some_name2

You can edit the configuration file using the edit-config script from the Netdata config directory.

cd /etc/netdata 2>/dev/null || cd /opt/netdata/etc/netdata
sudo ./edit-config go.d/mongodb.conf

Examples

TCP socket

An example configuration.

jobs:
  - name: local
    uri: mongodb://netdata:password@localhost:27017

With databases metrics

An example configuration.

jobs:
  - name: local
    uri: mongodb://netdata:password@localhost:27017
    databases:
      includes:
        - "* *"

Multi-instance

Note: When you define multiple jobs, their names must be unique.

Local and remote instances.

jobs:
  - name: local
    uri: mongodb://netdata:password@localhost:27017

  - name: remote
    uri: mongodb://netdata:[email protected]:27017

Alerts

There are no alerts configured by default for this integration.

Metrics

Metrics grouped by scope.

The scope defines the instance that the metric belongs to. An instance is uniquely identified by a set of labels.

• WireTiger metrics are available only if WiredTiger is used as the storage engine.
• Sharding metrics are available on shards only for mongos.

Per MongoDB instance

These metrics refer to the entire monitored application.

This scope has no labels.

Metrics:

Per lock type

These metrics refer to the lock type.

Labels:

Metrics:

Per commit type

These metrics refer to the commit type.

Labels:

Metrics:

Per database

These metrics refer to the database.

Labels:

Metrics:

Per replica set member

These metrics refer to the replica set member.

Labels:

Metrics:

Per shard

These metrics refer to the shard.

Labels:

Metrics:

Live Data

This collector exposes real-time functions for interactive troubleshooting in the Live tab.

Top Queries

Retrieves profiled query statistics from MongoDB system.profile collection.

This function queries the system.profile collection across all user databases (excluding admin, local, config) to retrieve slow or sampled queries captured by the MongoDB profiler. It provides detailed execution metrics including timing, document counts, and execution plan information.

Use cases:

• Identify slow queries that exceed the profiling threshold
• Analyze query patterns by examining docs examined vs docs returned ratios
• Detect collection scans (COLLSCAN) that may need index optimization

Query text is truncated at 4096 characters for display purposes.

Prerequisites

Enable MongoDB profiling

Database profiling must be enabled on each database you want to monitor, and the function must be enabled in the collector configuration.

1. Enable profiling on a database (profile slow queries > 100ms):

   javascriptCopy

   use myDatabase
   db.setProfilingLevel(1, { slowms: 100 })
   

2. Or profile all operations (level 2, use with caution):

   javascriptCopy

   db.setProfilingLevel(2)
   

3. Verify profiling status:

   javascriptCopy

   db.getProfilingStatus()
   

4. Enable the function in Netdata collector config:

   yamlCopy

   jobs:
     - name: local
       uri: mongodb://localhost:27017
       top_queries_function_enabled: true
   

:::info

• Profiling level 0 = off, 1 = slow operations only, 2 = all operations
• The slowms threshold determines which queries are captured at level 1
• system.profile is a capped collection; old entries are automatically removed
• System databases (admin, local, config) are excluded from profiling queries

:::

Parameters

Returns

Profiled query statistics from system.profile. Each row represents a single profiled operation with execution metrics and plan details.

Troubleshooting

Debug Mode

Important: Debug mode is not supported for data collection jobs created via the UI using the Dyncfg feature.

To troubleshoot issues with the mongodb collector, run the go.d.plugin with the debug option enabled. The output should give you clues as to why the collector isn't working.

• Navigate to the plugins.d directory, usually at /usr/libexec/netdata/plugins.d/. If that's not the case on your system, open netdata.conf and look for the plugins setting under [directories].

  bashCopy

  cd /usr/libexec/netdata/plugins.d/
  

• Switch to the netdata user.

  bashCopy

  sudo -u netdata -s
  

• Run the go.d.plugin to debug the collector:

  bashCopy

  ./go.d.plugin -d -m mongodb
  

  To debug a specific job:

  bashCopy

  ./go.d.plugin -d -m mongodb -j jobName
  

Getting Logs

If you're encountering problems with the mongodb collector, follow these steps to retrieve logs and identify potential issues:

• Run the command specific to your system (systemd, non-systemd, or Docker container).
• Examine the output for any warnings or error messages that might indicate issues. These messages should provide clues about the root cause of the problem.

System with systemd

Use the following command to view logs generated since the last Netdata service restart:

journalctl _SYSTEMD_INVOCATION_ID="$(systemctl show --value --property=InvocationID netdata)" --namespace=netdata --grep mongodb

System without systemd

Locate the collector log file, typically at /var/log/netdata/collector.log, and use grep to filter for collector's name:

grep mongodb /var/log/netdata/collector.log

Note: This method shows logs from all restarts. Focus on the latest entries for troubleshooting current issues.

Docker Container

If your Netdata runs in a Docker container named "netdata" (replace if different), use this command:

docker logs netdata 2>&1 | grep mongodb