Typically, connecting to a Mongos node in an ApsaraDB for MongoDB sharded cluster instance is sufficient for reading and writing data. To read the Oplog of a shard node, you must apply for an endpoint for that shard.
Prerequisites
A sharded cluster instance is created.
The protocol is MongoDB.
Background information
An ApsaraDB for MongoDB sharded cluster instance consists of three components: Mongos, Shard, and Configserver. You can select the number and configuration of shard components to create sharded cluster instances with different performance levels. For more information, see Cluster architecture.
Usage notes
After you apply for a shard endpoint, the system creates an endpoint for the primary, secondary, and read-only nodes in the shard. Each endpoint requires one IP address. Ensure that you have a sufficient number of IP addresses available.
The network type of the endpoint that you apply for must be the same as the network type of the Mongos node.
After a shard endpoint is created, it cannot be modified.
The procedure in this topic describes how to apply for a private endpoint for a shard. To access the shard over the Internet, you must first apply for a private endpoint, set an account and password, and then apply for a public endpoint. For more information about how to apply for a public endpoint, see Apply for a public endpoint.
If your instance uses local disks, you can apply for a direct connection account when you apply for the shard endpoint. If your instance uses cloud disks, you must first create a direct connection account on the Account Management page before you apply for the shard endpoint.
You can apply for an endpoint only for a shard in an ApsaraDB for MongoDB sharded cluster instance.
Procedure
Instances that use cloud disks
When you apply for a shard endpoint for an instance that uses cloud disks, existing connections may experience transient connections. Ensure that your application has an automatic reconnection mechanism. We recommend that you perform this operation during off-peak hours.
Go to the Sharded Cluster Instances page. In the upper-left corner of the page, select a resource group and a region. Then, click the ID of the target instance.
Create a shard account.
NoteYou only need to create a shard account the first time you apply for a shard endpoint for the instance. You do not need to create the account for subsequent applications.
In the navigation pane on the left, click Accounts.
Click the Create Account button.
In the Create Account (Shard Only) panel, enter an account name and a password.
NoteThe shard account has read-only permissions.
Parameter
Description
Account Name
Create an account that meets the following requirements:
Starts with a lowercase letter.
Consists of lowercase letters, digits, or underscores (_).
Is 4 to 16 characters in length.
NoteKeywords cannot be used as account names in ApsaraDB for MongoDB.
The account has read-only permissions.
Account Password
Set a password that meets the following requirements:
Consists of at least three of the following character types: uppercase letters, lowercase letters, digits, and special characters.
The special characters are !@#$%^&*()_+-=.
Is 8 to 32 characters in length.
NoteApsaraDB for MongoDB lets you reset the passwords of accounts for Configserver and shard nodes. For more information, see Reset a password.
Confirm Password
Enter the password again.
Click OK.
Create a shard endpoint.
In the navigation pane on the left, click Database Connections.
In the PrivateLink - VPC section, click Apply For Shard Endpoint.
Set the following parameters in the Apply For Shard Endpoint panel.
Parameter
Description
Node Type
Fixed to Shard.
Select Node ID
Select the ID of the node for which you want to create an endpoint.
Click OK.
On the Database Connections page, you can view the endpoint.
Wait for the instance status to change from Creating Network Connection to Running.
In the PrivateLink - VPC section, you can view the endpoint of the node.
Instances that use local disks
Alternatively, on the Basic Information page of the instance, in the Shard List section, click Add Shard. Then, enable a direct connection to the shard and apply for an endpoint for the shard node in the Apply For Shard Direct Connection Endpoint section.
Go to the Sharded Cluster Instances page. In the upper-left corner of the page, select a resource group and a region. Then, click the ID of the target instance.
In the navigation pane on the left, click Database Connections.
In the PrivateLink - VPC section, click Apply for Shard Endpoint.
In the Apply For Shard panel, you can set the following parameters.
Parameter
Description
Node Type
Fixed to Shard.
Select Node ID
Select the ID of the node for which you want to create an endpoint.
Account Name
Create an account that meets the following requirements:
Starts with a lowercase letter.
Consists of lowercase letters, digits, or underscores (_).
Is 4 to 16 characters in length.
NoteKeywords cannot be used as account names in ApsaraDB for MongoDB.
The account has read-only permissions.
When you apply for an endpoint for a shard or Configserver node for the first time, you must set an account and password. You do not need to set them again for subsequent applications.
Account Password
Set a password that meets the following requirements:
Consists of at least three of the following character types: uppercase letters, lowercase letters, digits, and special characters.
The special characters are !@#$%^&*()_+-=.
Is 8 to 32 characters in length.
NoteApsaraDB for MongoDB lets you reset the passwords of accounts for Configserver and shard nodes. For more information, see Reset a password.
Confirm Password
Enter the password again.
Click OK.
On the Database Connections page, you can view the endpoint.
Wait for the instance status to update from Creating Network Connection to Running.
In the PrivateLink - VPC section, you can view the endpoint of the node.
References
If you no longer need the shard endpoint, you can release it. For more information, see Release the endpoint of a shard or Configserver node.