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.

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:

Metric	Dimensions	Unit
mongodb.operations_rate	reads, writes, commands	operations/s
mongodb.operations_latency_time	reads, writes, commands	milliseconds
mongodb.operations_by_type_rate	insert, query, update, delete, getmore, command	operations/s
mongodb.document_operations_rate	inserted, deleted, returned, updated	operations/s
mongodb.scanned_indexes_rate	scanned	indexes/s
mongodb.scanned_documents_rate	scanned	documents/s
mongodb.active_clients_count	readers, writers	clients
mongodb.queued_operations_count	reads, writes	operations
mongodb.cursors_open_count	open	cursors
mongodb.cursors_open_no_timeout_count	open_no_timeout	cursors
mongodb.cursors_opened_rate	opened	cursors/s
mongodb.cursors_timed_out_rate	timed_out	cursors/s
mongodb.cursors_by_lifespan_count	le_1s, 1s_5s, 5s_15s, 15s_30s, 30s_1m, 1m_10m, ge_10m	cursors
mongodb.transactions_count	active, inactive, open, prepared	transactions
mongodb.transactions_rate	started, aborted, committed, prepared	transactions/s
mongodb.connections_usage	available, used	connections
mongodb.connections_by_state_count	active, threaded, exhaust_is_master, exhaust_hello, awaiting_topology_changes	connections
mongodb.connections_rate	created	connections/s
mongodb.asserts_rate	regular, warning, msg, user, tripwire, rollovers	asserts/s
mongodb.network_traffic_rate	in, out	bytes/s
mongodb.network_requests_rate	requests	requests/s
mongodb.network_slow_dns_resolutions_rate	slow_dns	resolutions/s
mongodb.network_slow_ssl_handshakes_rate	slow_ssl	handshakes/s
mongodb.memory_resident_size	used	bytes
mongodb.memory_virtual_size	used	bytes
mongodb.memory_page_faults_rate	pgfaults	pgfaults/s
mongodb.memory_tcmalloc_stats	allocated, central_cache_freelist, transfer_cache_freelist, thread_cache_freelists, pageheap_freelist, pageheap_unmapped	bytes
mongodb.wiredtiger_concurrent_read_transactions_usage	available, used	transactions
mongodb.wiredtiger_concurrent_write_transactions_usage	available, used	transactions
mongodb.wiredtiger_cache_usage	used	bytes
mongodb.wiredtiger_cache_dirty_space_size	dirty	bytes
mongodb.wiredtiger_cache_io_rate	read, written	pages/s
mongodb.wiredtiger_cache_evictions_rate	unmodified, modified	pages/s
mongodb.sharding_nodes_count	shard_aware, shard_unaware	nodes
mongodb.sharding_sharded_databases_count	partitioned, unpartitioned	databases
mongodb.sharding_sharded_collections_count	partitioned, unpartitioned	collections

Per lock type

These metrics refer to the lock type.

Labels:

Label	Description
lock_type	lock type (e.g. global, database, collection, mutex)

Metrics:

Metric	Dimensions	Unit
mongodb.lock_acquisitions_rate	shared, exclusive, intent_shared, intent_exclusive	acquisitions/s

Per commit type

These metrics refer to the commit type.

Labels:

Label	Description
commit_type	commit type (e.g. noShards, singleShard, singleWriteShard)

Metrics:

Metric	Dimensions	Unit
mongodb.transactions_commits_rate	success, fail	commits/s
mongodb.transactions_commits_duration_time	commits	milliseconds

Per database

These metrics refer to the database.

Labels:

Label	Description
database	database name

Metrics:

Metric	Dimensions	Unit
mongodb.database_collection_count	collections	collections
mongodb.database_indexes_count	indexes	indexes
mongodb.database_views_count	views	views
mongodb.database_documents_count	documents	documents
mongodb.database_data_size	data_size	bytes
mongodb.database_storage_size	storage_size	bytes
mongodb.database_index_size	index_size	bytes

Per replica set member

These metrics refer to the replica set member.

Labels:

Label	Description
repl_set_member	replica set member name

Metrics:

Metric	Dimensions	Unit
mongodb.repl_set_member_state	primary, startup, secondary, recovering, startup2, unknown, arbiter, down, rollback, removed	state
mongodb.repl_set_member_health_status	up, down	status
mongodb.repl_set_member_replication_lag_time	replication_lag	milliseconds
mongodb.repl_set_member_heartbeat_latency_time	heartbeat_latency	milliseconds
mongodb.repl_set_member_ping_rtt_time	ping_rtt	milliseconds
mongodb.repl_set_member_uptime	uptime	seconds

Per shard

These metrics refer to the shard.

Labels:

Label	Description
shard_id	shard id

Metrics:

Metric	Dimensions	Unit
mongodb.sharding_shard_chunks_count	chunks	chunks

Alerts

There are no alerts configured by default for this integration.

Setup

Prerequisites

Create a read-only user

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

• Authenticate as the admin user:

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

• Create a user:

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

Configuration

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_name1

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

Options

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

Config options

Name	Description	Default	Required
update_every	Data collection frequency.	5	no
autodetection_retry	Recheck interval in seconds. Zero means no recheck will be scheduled.	0	no
uri	MongoDB connection string. See URI syntax.	mongodb://localhost:27017	yes
timeout	Query timeout in seconds.	1	no
databases	Databases selector. Determines which database metrics will be collected.		no

Examples

TCP socket

An example configuration.

Config

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

With databases metrics

An example configuration.

Config

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.

Config

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

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

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].

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

• Switch to the netdata user.

  sudo -u netdata -s

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

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

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