Connect to a Database Deployment
Considerations
Atlas does not guarantee that host names remain consistent with respect to node types during topology changes.
Example
If you have a cluster named foo123 containing an analytics
node foo123-shard-00-03-a1b2c.mongodb.net:27017, Atlas does
not guarantee that specific host name will continue to refer to an
analytics node after a topology change, such as
scaling a cluster to modify its
number of nodes or regions.
Improve Connection Performance for Sharded Clusters Behind a Private Endpoint
Atlas can generate an optimized SRV connection string for sharded
clusters using the load balancers from your private endpoint
service. When you use an optimized connection string, Atlas limits
the number of connections per mongos between your application and
your sharded cluster. The limited connections per mongos
improve performance during spikes in connection counts.
Note
Atlas doesn't support optimized connection strings for clusters that run on Google Cloud or Azure.
To use an optimized connection string, you must meet all of the following criteria:
Ensure that the sharded cluster runs on AWS.
Ensure that the sharded cluster runs MongoDB version 5.0 or later. If your cluster currently runs an earlier version of MongoDB, upgrade your cluster's MongoDB version to version 5.0 or later to use an optimized SRV connection string.
Set up a private endpoint for your cluster.
Use either:
A single-region cluster or
A multi-region cluster with regionalized private endpoints enabled. Only the AWS regions in a multi-region cluster support an optimized SRV connection string.
Atlas doesn't support optimized connections to multi-region clusters using a single SRV record.
Connect using one of the following methods:
Connect using a driver that meets or exceeds the minimum driver version for optimized connections.
Note
If your cluster meets the criteria for optimized SRV strings, Atlas generates an Optimized SRV Connection string for you. If your cluster ever had legacy connection strings, Atlas maintains those strings indefinitely and includes a Legacy SRV Connection string when you select the Private Endpoint connection type. Consider switching to the Optimized SRV Connection for optimal performance and update your connection string wherever you use it.
If you create the cluster and enable private endpoints after
Atlas released this feature, Atlas displays the optimized
connection string by default when you select the
Private Endpoint connection type. You can identify an
optimized connection string by the addition of lb to the
connection string as shown in the following example:
mongodb+SRV://User1:P@ssword@cluster0-pl-0-lb.oq123.mongodb-dev.net/
To disable optimized connection strings for clusters that don't have the Legacy SRV Connection option, contact support.
Use Optimized Connection Strings with a Driver
To learn how to connect using a driver and an optimized connection string, select the Private Endpoint Connection tab in the Connect Your Application procedure.
Use Optimized Connection Strings with Compass
To learn how to connect using Compass and an optimized connection string, select the Private Endpoint Connection tab in the Connect to your Database Deployment procedure.
Use Optimized Connection Strings with mongosh
To learn how to connect using mongosh and an optimized connection
string, select the Private Endpoint Connection tab in the
Connect to your Database Deployment procedure.
Prerequisites
IP Access List
To access a database deployment, you must connect from an IP address on the Atlas project's IP access list. If you need to add an IP address to the IP access list, you can do so in the Connect dialog. You can also add the IP address from the Network Access tab.
Database User
To access a database deployment, you must create a database user with access to the desired databases on your Atlas database deployment. Database users are separate from Atlas users. Database users have access to MongoDB databases, while Atlas users have access to the Atlas application itself.
You can create a database user to access your Atlas database deployment in the Connect dialog. You can also add the database user from the Database Deployment view.
Open Ports 27015 to 27017 to Access Atlas Databases
Make sure your application can reach your MongoDB Atlas environment. To add the inbound network access from your application environment to Atlas, do one of the following:
Add the public IP addresses to your IP access list
Use VPC / VNet peering to add private IP addresses.
Tip
See also:
If your firewall blocks outbound network connections, you must also open outbound access from your application environment to Atlas. You must configure your firewall to allow your applications to make outbound connections to ports 27015 to 27017 to TCP traffic on Atlas hosts. This grants your applications access to databases stored on Atlas.
Note
By default, MongoDB Atlas clusters do not need to be able to initiate connections to your application environments. If you wish to enable Atlas clusters with LDAP authentication and authorization, you must allow network access from Atlas clusters directly to your secure LDAP. You can allow access to your LDAP by using public or private IPs as long as a public DNS hostname points to an IP that the Atlas clusters can access.
If you are not using VPC / VNet peering and plan to connect to Atlas using public IP addresses, see the following pages for additional information:
Connect to Your Database Deployment
In order to connect to your database deployment, you must get your deployment's connection string. Once you have the connection string, you can connect to your deployment by using the following connection methods:
Note
To connect using mongodump or mongorestore,
use the Command Line Tools tab. The tab
creates an auto-generated template for connecting to your Atlas
database deployment with your preferred tool.
To get your deployment's connection string, you can use the Atlas CLI or Atlas UI:
Troubleshooting
If you are experiencing issues connecting to your database deployment, see Troubleshoot Connection Issues.