MongoDB Atlas

Connect a MongoDB Atlas cluster as a Cyntex source or target for full-load batch reads and real-time CDC pipelines via the Atlas-managed Oplog.

Supported versions: MongoDB Atlas 5.0.15 and above (MongoDB 5.0+ recommended for cross-version compatibility)
Supported modes: batch, cdc

Prerequisites

1. Configure network access in Atlas:

• In the Atlas left sidebar, click Network Access.
• Click Add IP Address.
• Enter the public IP of your Cyntex agent in CIDR notation (e.g., 203.0.113.42/32) and click Confirm.

2. Create a database user in Atlas:

• In the Atlas left sidebar, click Database Access.
• Click Add New Database User.
• Select Password authentication.
• Set the built-in role:
  • As a source: Read Any Database
  • As a target: Read and Write to Any Database
• Click Add User.

3. Retrieve the connection URI:

• In the Atlas left sidebar, click Database.
• Locate your cluster and click Connect.
• Select Connect your application and copy the connection string.
• The URI includes your username and password and looks like:

  mongodb+srv://<username>:<password>@cluster0.example.mongodb.net/<database>?retryWrites=true&w=majority

DSL Configuration

apiVersion: cyntex/v1
kind: source
id: my-mongodb-atlas
connector: mongodb-atlas
mode: cdc   # batch | cdc

config:
  connectionMode: uri
  uri: "mongodb+srv://${ATLAS_USER}:${ATLAS_PASS}@cluster0.example.mongodb.net/mydb?retryWrites=true&w=majority"
  # The database name must be specified in the URI path (e.g., /mydb above).
  # Omitting the database from the URI will cause a connection error.

options:
  start_from: latest

tables:
  - name: users
  - name: /orders_.*/

Config Reference

Field	Required	Default	Description
connectionMode	Yes	uri	Must be uri for MongoDB Atlas. Atlas connections always use the mongodb+srv:// URI scheme.
uri	Yes	—	Full Atlas connection URI including credentials and the target database name in the path. Example: mongodb+srv://user:pass@cluster.mongodb.net/dbname?retryWrites=true&w=majority

Notes

• Database name is mandatory in the URI: The database must be specified as the path component of the URI (e.g., /mydb). A URI without a database name will fail with databaseName can not be null.
• mongodb+srv scheme: Atlas uses DNS seed list discovery via the +srv scheme. Do not replace it with a plain mongodb:// URI with explicit host:port unless you are connecting to a specific Atlas private endpoint.
• Network access: Cyntex agent IPs must be whitelisted in the Atlas Network Access panel. If your agent IP changes (e.g., in a dynamic cloud environment), update the whitelist accordingly.
• Oplog access: Atlas manages the Oplog automatically. The minimum Oplog window available depends on your Atlas tier. For M10+ clusters, Atlas supports custom Oplog retention.
• UPDATE events and full document filling: Enabled by default. Atlas CDC UPDATE events return only the modified fields; Cyntex performs a reverse lookup to fill in the complete document. Disable this in advanced node settings only if the downstream target supports sparse updates.
• Cross-version sync: When syncing between two MongoDB Atlas clusters, it is strongly recommended that both source and target run MongoDB 5.0 or above to ensure data type compatibility.
• Shard index sync: When using Atlas as a target in a sharded cluster configuration, enable syncPartitionProperties in advanced node settings to replicate sharding attributes.