Collector Type: Agent

Category: Application Monitors

Application Name: MongoDB

Global Template Name: LINUX MongoDB Template

Introduction

MongoDB is a cross-platform document-oriented database program. Classified as a NoSQL database program, MongoDB uses JSON-like documents with optional schemas. MongoDB is developed by MongoDB Inc. and licensed under the Server Side Public License.

MongoDB is classified as a NoSQL database, stores data using a flexible document data model that is similar to JSON documents with dynamic schemas (called as BSON). Documents contain one or more fields, including arrays, binary data and sub-documents.

MongoDB provides auto-sharding for horizontal scale out.

Native replication and automatic leader election supports high availability across racks and data centers.

MongoDB makes extensive use of RAM, providing in-memory speed and on-disk capacity.

Some of the main features include:

Document-oriented Instead of taking a business subject and breaking it up into multiple relational structures, MongoDB can store the business subject in the minimal number of documents. For example, instead of storing title and author information in two distinct relational structures, title, author, and other title-related information can all be stored in a single document called Book, which is much more intuitive and usually easier to work with.

Ad hoc queries MongoDB supports search by field, range queries, regular expression searches. Queries can return specific fields of documents and also include user-defined JavaScript functions.

Indexing Any field in a MongoDB document can be indexed (indices in MongoDB are conceptually similar to those in RDBMSes). Secondary indices are also available.

Replication MongoDB provides high availability with replica sets. A replica set consists of two or more copies of the data. Each replica set member may act in the role of primary or secondary replica at any time. The primary replica performs all writes and reads by default. Secondary replicas maintain a copy of the data on the primary using built-in replication. When a primary replica fails, the replica set automatically conducts an election process to determine which secondary should become the primary. Secondaries can also perform read operations, but the data is eventually consistent by default.

Load balancing MongoDB scales horizontally using sharding. The user chooses a shard key, which determines how the data in a collection will be distributed. The data is split into ranges (based on the shard key) and distributed across multiple shards. (A shard is a master with one or more slaves.) MongoDB can run over multiple servers, balancing the load and/or duplicating data to keep the system up and running in case of hardware failure. Automatic configuration is easy to deploy, and new machines can be added to a running database.

File storage MongoDB can be used as a file system, taking advantage of load balancing and data replication features over multiple machines for storing files. This function, called GridFS, is included with MongoDB drivers and available with no difficulty for development languages. MongoDB exposes functions for file manipulation and content to developers. Instead of storing a file in a single document, GridFS divides a file into parts, or chunks, and stores each of those chunks as a separate document. In a multi-machine MongoDB system, files can be distributed and copied multiple times between machines transparently, thus effectively creating a load-balanced and fault-tolerant system.

Aggregation MapReduce can be used for batch processing of data and aggregation operations. The aggregation framework enables users to obtain the kind of results for which the SQL GROUP BY clause is used.

Server-side JavaScript execution JavaScript can be used in queries, aggregation functions (such as MapReduce), and sent directly to the database to be executed.

Capped collections MongoDB supports fixed-size collections called capped collections. This type of collection maintains insertion order and, once the specified size has been reached, behaves like a circular queue.

Prerequisites: python-pymongo package is needed to be installed in the server vistara agent runs on.

Parameters

NameDefault Value
Host IP Address

The host on which MongoDB is running.
127.0.0.1
User Name

The username of the MongoDB Server.
NA
Password

The password of the MongoDB Server.
NA
Port

The port on which Mongo Server is running.
27017
Replication Set Name

The latest vistara agent can detect the Replica set name dynamically, if available.
NA

Note: All field attributes are mandatory, use default values wherever applicable.

Collected Metrics

Metric NameDisplay Name
mongodb.uptime

Uptime in minutes.
MongoDB-Uptime
mongodb.activeclients

Current active, read and write clients.
MongoDB-ActiveClients
mongodb.memory

MongoDB resident, virtual, mapped memory in MB.
MongoDB-Memory
mongodb.lock

Lock percentage in %percentage.
MongoDB-Lock
mongodb.connections

MongoDB current and available connections.
MongoDB-Connections
mongodb.heap usage

Heap Usage in MB.
MongoDB-HeapUsage
mongodb.pagefaults

Page Faults per second.
MongoDB-PageFaults
mongodb.btree

Provides Index Counters details as Accesses, Hits, Misses, Resets, Miss_ratio.
MongoDB-BTree
mongodb.networkrequests

Network Requests per second.
MongoDB-NetworkRequests
mongodb.currentqueue

Current readers and writers in Queue.
MongoDB-CurrentQueue
mongodb.opcounters

Provides opcounts for operations like insert, update, query, delete, getmore, command(per second).
MongoDB-OPCounters
mongodb.replicaprimary

Check if the primary server of a replica set has changed.
MongoDB-ReplicaPrimary
mongodb.replicationlag

Checks the replication lag in seconds.
MongoDB-ReplicationLag
mongodb.replicationstate

Replication states will be the following cases: StartingPhase1(0), Primary(1), Secondary(2), Recoverying(3), Fatal Error(4), StartingPhase2(5), Arbiter(7), Down(8), Not_Running_with_Replication(-1).
MongoDB-ReplicationState
mongodb-journalcommits_in_wl

Provides the number of journal commits that occurred in the write lock.
MongoDB-JournalCommitsInWL
mongodb.size

Provides the size of individual databases in Gigabytes (GB's).
MongoDB-Size
mongodb.index size

Provides the Index size of databases in KBs.
MongoDB-IndexSize