Creating Data Connections

You can create data connections by configuring data sources. Based on the data connections of the Management Center, DataArts Studio performs data development, governance, services, and operations on the data lake base.

Constraints

RDS data connections depend on OBS. If OBS is unavailable in the same region as DataArts Studio, RDS data connections are not supported.
For host connections, only Linux hosts are supported.
If changes occur in the connected data lake (for example, the MRS cluster capacity is expanded), you need to edit and save the connection.

Prerequisites

You have created a data lake to connect, for example, a database or cloud service supported by DataArts Studio.
- Before creating a DWS data connection, ensure that you have created a cluster in DWS and have the permissions required to view Key Management Service (KMS) keys.
- Before creating an MRS HBase, MRS Hive, MRS Kafka, MRS Ranger, MRS Presto, or MRS Spark connection, ensure that you have bought an MRS cluster and selected required components.
- Before creating an RDS data connection, ensure that you have bought an RDS DB instance. Currently, DataArts Studio supports only MySQL and PostgreSQL databases in RDS.
The data lake to connect communicates with the DataArts Studio instance properly.
- If the data lake is an on-premises database, a public network or a dedicated connection is required. Ensure that the host where the data source is located can access the public network and the port has been enabled in the firewall rule.
- If the data lake is a cloud service (such as DWS and MRS), the following requirements must be met for network interconnection:
  - If the CDM cluster in the DataArts Studio instance and the cloud service are in different regions, a public network or a dedicated connection is required.
  - If the CDM cluster in the DataArts Studio instance and the cloud service are in the same region, VPC, subnet, and security group, they can communicate with each other by default. If they are in the same VPC but in different subnets or security groups, you must configure routing rules and security group rules. For details about how to configure routing rules, see configuring routes. For details about how to configure security group rules, see configuring security group rules.
  - The cloud service instance and the DataArts Studio workspace belong to the same enterprise project. If they do not, you can modify the enterprise project of the workspace.

Creating a Data Connection

On the DataArts Studio console, locate a workspace and click Management Center.

In the navigation pane, choose Manage Data Connections.
Figure 1 Manage Data Connections

On the Data Connection Management page, click Create Data Connection. Select a data connection type and set the relevant parameters. See Table 1.

Figure 2 Create Data Connection

**Table 1** Data connections
Data Connection Type	Link
MRS Hive	Table 2
MRS HBase	Table 3
MRS Kafka	Table 4
MRS Ranger	Table 10
DWS	Table 7
DLI	Table 8
ORACLE	Table 9
MRS Spark	Table 5
RDS	See Table 6. You can also create RDS connections to relational databases, such as MySQL, PostgreSQL, and Dameng databases.
MRS Presto	Table 11
MySQL (pending offline)	You are not advised to select this connection type. Instead, You are advised to select RDS. For details, see Table 6.
Host Connection	See Table 12.

Click Test to test connectivity of the data connection. If the test passes, the data connection is created.
After the test is successful, click OK. The system will create the data connection for you.

Data Connection Parameter Description

**Table 2** MRS Hive data connection
Parameter	Mandatory	Description
Data Connection Name	Yes	The name of the data connection to create. Data connection names can contain 1 to 50 characters. They can include only letters, numbers, underscores (_), and hyphens (-).
Tag	No	The attribute of the data connection to create. Tags make management easier. You can set a tag or select a tag created in Tags from the drop-down list. NOTE: The name of the tag. Only letters, numbers, and underscores (_) are allowed. Tag names cannot start with underscores (_). Enter up to 100 characters.
Cluster Name	Yes	The name of the MRS cluster. Select an MRS cluster that Hive belongs to. Only MRS clusters are supported. A Hadoop cluster can be selected only after it is managed by MRS. All the MRS clusters with the same project ID and enterprise project are displayed. If the connection fails after you select a cluster, check whether the MRS cluster can communicate with the CDM instance which functions as the agent. They can communicate with each other in the following scenarios: If the CDM cluster in the DataArts Studio instance and the MRS cluster are in different regions, a public network or a dedicated connection is required. If the Internet is used for communication, ensure that an EIP has been bound to the CDM cluster, and the MRS cluster can access the Internet and the port has been enabled in the firewall rule. If the CDM cluster in the DataArts Studio instance and the MRS cluster are in the same region, VPC, subnet, and security group, they can communicate with each other by default. If they are in the same VPC but in different subnets or security groups, you must configure routing rules and security group rules. For details about how to configure routing rules, see configuring routes. For details about how to configure security group rules, see configuring security group rules. The MRS cluster and the DataArts Studio workspace belong to the same enterprise project. If they do not, you can modify the enterprise project of the workspace.
Connection Type	Yes	Connection type. Proxy connection is recommended. Proxy connection: An agent (CDM cluster) is used to access MRS clusters. This method supports all versions of MRS clusters. MRS API connection: MRS APIs are used to access MRS clusters. This method supports only MRS clusters of the 2.X or a later version. When you select MRS API connection, pay attention to the following restrictions: Tables and fields cannot be viewed. When the SQL editor is used to run SQL statements, the execution results can be displayed only in logs. This method is not supported by data governance functions such as DataArts Architecture, DataArts Quality, and DataArts Catalog. If a cluster managed by MRS is connected, disable OBS for DataArts Factory. When OBS is disabled, some functions (such as backup management and resource management) are restricted. NOTE: Select Proxy connection for Connection Type so that the DataArts Architecture, DataArts Quality, DataArts Catalog, and DataArts DataService components can use the MRS connection.
Username	No	The username of the MRS cluster. This parameter is mandatory when Connection Type is set to Proxy connection. If a new MRS user is used for connection, you need to log in to Manager and change the initial password. You cannot create a data connection for an MRS security cluster as user admin. User admin is the management page user by default and cannot be used as the authentication user of a security cluster. You can create an MRS user by referring to Creating a Kerberos Authentication User for an MRS Security Cluster. When creating an MRS data connection, set Username and Password to the new MRS username and password. NOTE: For clusters of MRS 3.1.0 or later, the user must at least have permissions of the Manager_viewer role to create data connections in Management Center. To perform database, table, and data operations on components, the user must also have user group permissions of the components. For clusters earlier than MRS 3.1.0, the user must have permissions of the Manager_administrator or System_administrator role to create data connections in Management Center. A user with only the Manager_tenant or Manager_auditor permission cannot create connections.
Password	No	The password for accessing the MRS cluster. This parameter is mandatory when Connection Type is set to Proxy connection.
KMS Key	No	The name of the KMS key. This parameter is mandatory when Connection Type is set to Proxy connection.
Agent	No	This parameter is mandatory when Connection Type is set to Proxy connection. MRS is not a fully managed service and cannot be directly connected to DataArts Studio. A CDM cluster can provide an agent for DataArts Studio to communicate with non-fully-managed services. Therefore, you need to select a CDM cluster when creating an MRS data connection. If no CDM cluster is available, create one through the DataArts Migration incremental package. As a network proxy, the CDM cluster must be able to communicate with the MRS cluster. To ensure network connectivity, the CDM cluster must be in the same region, AZ, VPC, and subnet as the MRS cluster. The security group rule must also allow the CDM cluster communicate with the MRS cluster.

**Table 3** MRS HBase data connection
Parameter	Mandatory	Description
Data Connection Name	Yes	The name of the data connection to create. Data connection names can contain 1 to 50 characters. They can include only letters, numbers, underscores (_), and hyphens (-).
Tag	No	The attribute of the data connection to create. Tags make management easier. You can set a tag or select a tag created in Tags from the drop-down list. NOTE: The name of the tag. Only letters, numbers, and underscores (_) are allowed. Tag names cannot start with underscores (_). Enter up to 100 characters.
Cluster Name	Yes	The name of the MRS cluster. Select an MRS cluster that Hive belongs to. Only MRS clusters are supported. A Hadoop cluster can be selected only after it is managed by MRS. All the MRS clusters with the same project ID and enterprise project are displayed. If the connection fails after you select a cluster, check whether the MRS cluster can communicate with the CDM instance which functions as the agent. They can communicate with each other in the following scenarios: If the CDM cluster in the DataArts Studio instance and the MRS cluster are in different regions, a public network or a dedicated connection is required. If the Internet is used for communication, ensure that an EIP has been bound to the CDM cluster, and the MRS cluster can access the Internet and the port has been enabled in the firewall rule. If the CDM cluster in the DataArts Studio instance and the MRS cluster are in the same region, VPC, subnet, and security group, they can communicate with each other by default. If they are in the same VPC but in different subnets or security groups, you must configure routing rules and security group rules. For details about how to configure routing rules, see configuring routes. For details about how to configure security group rules, see configuring security group rules. The MRS cluster and the DataArts Studio workspace belong to the same enterprise project. If they do not, you can modify the enterprise project of the workspace.
Username	Yes	Username of the MRS cluster You cannot create a data connection for an MRS security cluster as user admin. User admin is the management page user by default and cannot be used as the authentication user of a security cluster. You can create an MRS user by referring to Creating a Kerberos Authentication User for an MRS Security Cluster. When creating an MRS data connection, set Username and Password to the new MRS username and password. NOTE: For clusters of MRS 3.1.0 or later, the user must at least have permissions of the Manager_viewer role to create data connections in Management Center. To perform database, table, and data operations on components, the user must also have user group permissions of the components. For clusters earlier than MRS 3.1.0, the user must have permissions of the Manager_administrator or System_administrator role to create data connections in Management Center. A user with only the Manager_tenant or Manager_auditor permission cannot create connections.
Password	Yes	Password for accessing the MRS cluster.
KMS Key	Yes	Name of the KMS key.
Agent	Yes	MRS is not a fully managed service and cannot be directly connected to DataArts Studio. A CDM cluster can provide an agent for DataArts Studio to communicate with non-fully-managed services. Therefore, you need to select a CDM cluster when creating an MRS data connection. If no CDM cluster is available, create one through the DataArts Migration incremental package. As a network proxy, the CDM cluster must be able to communicate with the MRS cluster. To ensure network connectivity, the CDM cluster must be in the same region, AZ, VPC, and subnet as the MRS cluster. The security group rule must also allow the CDM cluster communicate with the MRS cluster.

**Table 4** MRS Kafka data connection
Parameter	Mandatory	Description
Data Connection Name	Yes	The name of the data connection to create. Data connection names can contain 1 to 50 characters. They can include only letters, numbers, underscores (_), and hyphens (-).
Tag	No	The attribute of the data connection to create. Tags make management easier. You can set a tag or select a tag created in Tags from the drop-down list. NOTE: The name of the tag. Only letters, numbers, and underscores (_) are allowed. Tag names cannot start with underscores (_). Enter up to 100 characters.
Cluster Name	Yes	The name of the MRS cluster. Select an MRS cluster that Hive belongs to. Only MRS clusters are supported. A Hadoop cluster can be selected only after it is managed by MRS. All the MRS clusters with the same project ID and enterprise project are displayed. If the connection fails after you select a cluster, check whether the MRS cluster can communicate with the CDM instance which functions as the agent. They can communicate with each other in the following scenarios: If the CDM cluster in the DataArts Studio instance and the MRS cluster are in different regions, a public network or a dedicated connection is required. If the Internet is used for communication, ensure that an EIP has been bound to the CDM cluster, and the MRS cluster can access the Internet and the port has been enabled in the firewall rule. If the CDM cluster in the DataArts Studio instance and the MRS cluster are in the same region, VPC, subnet, and security group, they can communicate with each other by default. If they are in the same VPC but in different subnets or security groups, you must configure routing rules and security group rules. For details about how to configure routing rules, see configuring routes. For details about how to configure security group rules, see configuring security group rules. The MRS cluster and the DataArts Studio workspace belong to the same enterprise project. If they do not, you can modify the enterprise project of the workspace.
Username	Yes	Username of the MRS cluster You cannot create a data connection for an MRS security cluster as user admin. User admin is the management page user by default and cannot be used as the authentication user of a security cluster. You can create an MRS user by referring to Creating a Kerberos Authentication User for an MRS Security Cluster. When creating an MRS data connection, set Username and Password to the new MRS username and password. NOTE: For clusters of MRS 3.1.0 or later, the user must at least have permissions of the Manager_viewer role to create data connections in Management Center. To perform database, table, and data operations on components, the user must also have user group permissions of the components. For clusters earlier than MRS 3.1.0, the user must have permissions of the Manager_administrator or System_administrator role to create data connections in Management Center. A user with only the Manager_tenant or Manager_auditor permission cannot create connections.
Password	Yes	Password for accessing the MRS cluster.
KMS Key	Yes	Name of the KMS key.
Agent	Yes	MRS is not a fully managed service and cannot be directly connected to DataArts Studio. A CDM cluster can provide an agent for DataArts Studio to communicate with non-fully-managed services. Therefore, you need to select a CDM cluster when creating an MRS data connection. If no CDM cluster is available, create one through the DataArts Migration incremental package. As a network proxy, the CDM cluster must be able to communicate with the MRS cluster. To ensure network connectivity, the CDM cluster must be in the same region, AZ, VPC, and subnet as the MRS cluster. The security group rule must also allow the CDM cluster communicate with the MRS cluster.

**Table 5** MRS Spark data connection
Parameter	Mandatory	Description
Data Connection Name	Yes	The name of the data connection to create. Data connection names can contain 1 to 50 characters. They can include only letters, numbers, underscores (_), and hyphens (-).
Tag	No	The attribute of the data connection to create. Tags make management easier. You can set a tag or select a tag created in Tags from the drop-down list. NOTE: The name of the tag. Only letters, numbers, and underscores (_) are allowed. Tag names cannot start with underscores (_). Enter up to 100 characters.
Cluster Name	Yes	The name of the MRS cluster. Select an MRS cluster that Hive belongs to. Only MRS clusters are supported. A Hadoop cluster can be selected only after it is managed by MRS. All the MRS clusters with the same project ID and enterprise project are displayed. If the connection fails after you select a cluster, check whether the MRS cluster can communicate with the CDM instance which functions as the agent. They can communicate with each other in the following scenarios: If the CDM cluster in the DataArts Studio instance and the MRS cluster are in different regions, a public network or a dedicated connection is required. If the Internet is used for communication, ensure that an EIP has been bound to the CDM cluster, and the MRS cluster can access the Internet and the port has been enabled in the firewall rule. If the CDM cluster in the DataArts Studio instance and the MRS cluster are in the same region, VPC, subnet, and security group, they can communicate with each other by default. If they are in the same VPC but in different subnets or security groups, you must configure routing rules and security group rules. For details about how to configure routing rules, see configuring routes. For details about how to configure security group rules, see configuring security group rules. The MRS cluster and the DataArts Studio workspace belong to the same enterprise project. If they do not, you can modify the enterprise project of the workspace.
Connection Type	Yes	Connection type. Proxy connection is recommended. Proxy connection: An agent (CDM cluster) is used to access MRS clusters. This method supports all versions of MRS clusters. MRS API connection: MRS APIs are used to access MRS clusters. This method supports only MRS clusters of the 2.X or a later version. When you select MRS API connection, pay attention to the following restrictions: Tables and fields cannot be viewed. When the SQL editor is used to run SQL statements, the execution results can be displayed only in logs. This method is not supported by data governance functions such as DataArts Architecture, DataArts Quality, and DataArts Catalog. If a cluster managed by MRS is connected, disable OBS for DataArts Factory. When OBS is disabled, some functions (such as backup management and resource management) are restricted. NOTE: Select Proxy connection for Connection Type so that the DataArts Architecture, DataArts Quality, DataArts Catalog, and DataArts DataService components can use the MRS connection.
Username	No	The username of the MRS cluster. This parameter is mandatory when Connection Type is set to Proxy connection. If a new MRS user is used for connection, you need to log in to Manager and change the initial password. You cannot create a data connection for an MRS security cluster as user admin. User admin is the management page user by default and cannot be used as the authentication user of a security cluster. You can create an MRS user by referring to Creating a Kerberos Authentication User for an MRS Security Cluster. When creating an MRS data connection, set Username and Password to the new MRS username and password. NOTE: For clusters of MRS 3.1.0 or later, the user must at least have permissions of the Manager_viewer role to create data connections in Management Center. To perform database, table, and data operations on components, the user must also have user group permissions of the components. For clusters earlier than MRS 3.1.0, the user must have permissions of the Manager_administrator or System_administrator role to create data connections in Management Center. A user with only the Manager_tenant or Manager_auditor permission cannot create connections.
Password	No	The password for accessing the MRS cluster. This parameter is mandatory when Connection Type is set to Proxy connection.
KMS Key	No	The name of the KMS key. This parameter is mandatory when Connection Type is set to Proxy connection.
Agent	No	This parameter is mandatory when Connection Type is set to Proxy connection. MRS is not a fully managed service and cannot be directly connected to DataArts Studio. A CDM cluster can provide an agent for DataArts Studio to communicate with non-fully-managed services. Therefore, you need to select a CDM cluster when creating an MRS data connection. If no CDM cluster is available, create one through the DataArts Migration incremental package. As a network proxy, the CDM cluster must be able to communicate with the MRS cluster. To ensure network connectivity, the CDM cluster must be in the same region, AZ, VPC, and subnet as the MRS cluster. The security group rule must also allow the CDM cluster communicate with the MRS cluster.

**Table 6** RDS data connection
Parameter	Mandatory	Description
Data Connection Name	Yes	The name of the data connection to create. Data connection names can contain 1 to 50 characters. They can include only letters, numbers, underscores (_), and hyphens (-).
Tag	No	The attribute of the data connection to create. Tags make management easier. You can set a tag or select a tag created in Tags from the drop-down list. NOTE: The name of the tag. Only letters, numbers, and underscores (_) are allowed. Tag names cannot start with underscores (_). Enter up to 100 characters.
IP Address	Yes	The address for accessing RDS. If the data source is RDS, you can obtain the address from the RDS console. Log in to the management console using the account. In the Service List, choose Relational Database Service. In the left navigation pane, choose Instances. Click the name of an instance. The basic information page of the instance is displayed. You can obtain the IP address on the Connection Information tab.
Port	Yes	The port for accessing RDS. If the data source is RDS, you can obtain the port from the RDS console. Log in to the management console using the account. In the Service List, choose Relational Database Service. In the left navigation pane, choose Instances. Click the name of an instance. The basic information page of the instance is displayed. You can obtain the database port on the Connection Information tab.
Driver Name	Yes	The name of the driver. The following values are available: com.mysql.jdbc.Driver org.postgresql.Driver
Driver File Path	Yes	Path of the driver file in the OBS bucket. You need to download the .jar driver file from the corresponding official website and upload it to the OBS bucket. MySQL driver: Download it from https://downloads.mysql.com/archives/c-j/. The 5.1.48 version is recommended. PostgreSQL driver: Download it from https://mvnrepository.com/artifact/org.postgresql/postgresql. The 42.1.4 version is recommended. NOTE: To update the driver, you must restart the CDM cluster in DataArts Migration and then edit the data connection to upload the driver.
Username	Yes	The username of the database. The username is required for creating a cluster.
Password	Yes	The password for accessing the database. The password is required for creating a cluster.
KMS Key	Yes	The name of the KMS key. To obtain the key: Log in to the management console using the account. Click Key Management Service and select Key Management Service from the list on the left. You can obtain the key name from the key list.
Agent	Yes	RDS is not a fully managed service and cannot be directly connected to DataArts Studio. A CDM cluster can provide an agent for DataArts Studio to communicate with non-fully-managed services. Therefore, you need to select a CDM cluster when creating an RDS data connection. If no CDM cluster is available, create one through the DataArts Migration incremental package. As a network proxy, the CDM cluster must be able to communicate with RDS. To ensure network connectivity, the CDM cluster must be in the same region, AZ, VPC, and subnet as RDS. The security group rule must also allow the CDM cluster to communicate with RDS.

**Table 7** DWS data connection
Parameter	Mandatory	Description
Data Connection Name	Yes	The name of the data connection to create. Data connection names can contain 1 to 50 characters. They can include only letters, numbers, underscores (_), and hyphens (-).
Tag	No	The attribute of the data connection to create. Tags make management easier. You can set a tag or select a tag created in Tags from the drop-down list. NOTE: The name of the tag. Only letters, numbers, and underscores (_) are allowed. Tag names cannot start with underscores (_). Enter up to 100 characters.
Manual	Yes	You can click to disable or enable the Manual function. When Manual is disabled, you do not need to enter the IP address and port. When Manual is enabled, you must enter the IP address and port.
IP Address	No	The IP address for accessing the cluster database through the internal network. This parameter is mandatory when Manual is enabled. The private network address is automatically generated when you create a cluster.
Port	No	The database port specified during DWS cluster creation. This parameter is mandatory when Manual is enabled. Ensure that you have enabled this port in the security group rule so that the DataArts Studio instance can connect to the database in the DWS cluster through this port.
SSL Connection	Yes	DWS supports SSL encryption and certificate authentication for communication between the client and server. You can use SSL Connection to set the communication mode. If SSL Connection is enabled, only SSL encryption can be used. If SSL Connection is disabled, both modes can be used. SSL Connection is disabled by default.
Cluster Name	No	This parameter is mandatory when Manual is disabled. Select a DWS cluster. All the DWS clusters with the same project ID and enterprise project are displayed.
Username	Yes	The database username, which is specified when the DWS cluster is created.
Password	Yes	The password for accessing the database, which is specified when the DWS cluster is created.
KMS Key	Yes	Name of the KMS key.
Agent	No	This parameter is mandatory when Connection Type is set to Proxy connection. Data Warehouse Service (DWS) is not a fully managed service and thus cannot be directly connected to DataArts Studio. A CDM cluster can provide an agent for DataArts Studio to communicate with non-fully-managed services. Therefore, you need to select a CDM cluster when creating a DWS data connection. If no CDM cluster is available, create one through the DataArts Migration incremental package. As a network proxy, the CDM cluster must be able to communicate with the DWS cluster. To ensure network connectivity, the CDM cluster must be in the same region, AZ, VPC, and subnet as the DWS cluster. The security group rule must also allow the CDM cluster communicate with the DWS cluster.

**Table 8** DLI data connection
Parameter	Mandatory	Description
Data Connection Name	Yes	The name of the data connection to create. Data connection names can contain 1 to 50 characters. They can include only letters, numbers, underscores (_), and hyphens (-).
Tag	No	The attribute of the data connection to create. Tags make management easier. You can set a tag or select a tag created in Tags from the drop-down list. NOTE: The name of the tag. Only letters, numbers, and underscores (_) are allowed. Tag names cannot start with underscores (_). Enter up to 100 characters.

**Table 9** Oracle data connection
Parameter	Mandatory	Description
Data Connection Name	Yes	The name of the data connection to create. Data connection names can contain 1 to 50 characters. They can include only letters, numbers, underscores (_), and hyphens (-).
Tag	No	The attribute of the data connection to create. Tags make management easier. You can set a tag or select a tag created in Tags from the drop-down list. NOTE: The name of the tag. Only letters, numbers, and underscores (_) are allowed. Tag names cannot start with underscores (_). Enter up to 100 characters.
ip	Yes	The IP address of the database to connect. Both public and private IP addresses are supported.
Port	Yes	The port of the database to connect.
Username	Yes	The username of the account for accessing the database. This account must have the permissions required to read and write data tables and metadata. NOTE: If you have the CONNECT permission (read-only permission) and are trying to create a connection, a message is displayed indicating that the table or schema does not exist. In this case, perform the following operations to grant permissions: Log in to the Oracle node as user root. Run the following command to switch to user oracle: su oracle Run the following command to log in to the database: sqlplus /nolog Run the following command to log in as user sys: connect sys as sysdba; Enter the password of user sys. . Run the following SQL statement to grant permissions: *GRANT SELECT ON GV_$INSTANCE to xxx;* In the preceding command, xxx indicates the name of the user to which the permissions will be granted.
Password	Yes	The user password.
Connection type	Yes	Select a connection type. SID SID indicates the ID of the Oracle database instance. One instance corresponds to only one database, but one database can correspond to multiple instances. Service Name It was introduced since Oracle8i and indicates the external service name of the Oracle database.
SID	No	This parameter is mandatory when Connection type is set to SID. SID indicates the ID of the Oracle database instance. One instance corresponds to only one database, but one database can correspond to multiple instances.
Service Name	No	This parameter is mandatory when Connection type is set to Service Name. It was introduced since Oracle8i and indicates the external service name of the Oracle database.
KMS Key	Yes	The name of the KMS key. To obtain the key: Log in to the management console using the created account. Click Key Management Service and select Key Management Service from the list on the left. You can obtain the key name from the key list.
Agent	Yes	Oracle is not a fully managed service and cannot be directly connected to DataArts Studio. A CDM cluster can provide an agent for DataArts Studio to communicate with non-fully-managed services. Therefore, you need to select a CDM cluster when creating an Oracle data connection. If no CDM cluster is available, create one through the DataArts Migration incremental package. As a network proxy, the CDM cluster must be able to communicate with Oracle.

**Table 10** MRS Ranger data connection
Parameter	Mandatory	Description
Data Connection Name	Yes	The name of the data connection to create. Data connection names can contain 1 to 50 characters. They can include only letters, numbers, underscores (_), and hyphens (-).
Tag	No	The attribute of the data connection to create. Tags make management easier. You can set a tag or select a tag created in Tags from the drop-down list. NOTE: The name of the tag. Only letters, numbers, and underscores (_) are allowed. Tag names cannot start with underscores (_). Enter up to 100 characters.
Cluster Name	Yes	The name of the MRS cluster. Select an MRS cluster that Hive belongs to. Only MRS clusters are supported. A Hadoop cluster can be selected only after it is managed by MRS. All the MRS clusters with the same project ID and enterprise project are displayed. If the connection fails after you select a cluster, check whether the MRS cluster can communicate with the CDM instance which functions as the agent. They can communicate with each other in the following scenarios: If the CDM cluster in the DataArts Studio instance and the MRS cluster are in different regions, a public network or a dedicated connection is required. If the Internet is used for communication, ensure that an EIP has been bound to the CDM cluster, and the MRS cluster can access the Internet and the port has been enabled in the firewall rule. If the CDM cluster in the DataArts Studio instance and the MRS cluster are in the same region, VPC, subnet, and security group, they can communicate with each other by default. If they are in the same VPC but in different subnets or security groups, you must configure routing rules and security group rules. For details about how to configure routing rules, see configuring routes. For details about how to configure security group rules, see configuring security group rules. The MRS cluster and the DataArts Studio workspace belong to the same enterprise project. If they do not, you can modify the enterprise project of the workspace. NOTE: Currently, DataArts Studio only supports connections to MRS Ranger in a cluster in security mode.
Username	Yes	The username of the MRS cluster. This parameter is mandatory when Connection Type is set to Proxy connection. If a new MRS user is used for connection, you need to log in to Manager and change the initial password. You cannot create a data connection for an MRS security cluster as user admin. User admin is the management page user by default and cannot be used as the authentication user of a security cluster. You can create an MRS user by referring to Creating a Kerberos Authentication User for an MRS Security Cluster. When creating an MRS data connection, set Username and Password to the new MRS username and password. NOTE: For clusters of MRS 3.1.0 or later, the user must at least have permissions of the Manager_viewer role to create data connections in Management Center. To perform database, table, and data operations on components, the user must also have user group permissions of the components. For clusters earlier than MRS 3.1.0, the user must have permissions of the Manager_administrator or System_administrator role to create data connections in Management Center. A user with only the Manager_tenant or Manager_auditor permission cannot create connections.
Password	Yes	Password for accessing the MRS cluster.
KMS Key	Yes	Name of the KMS key.
Agent	Yes	MRS is not a fully managed service and cannot be directly connected to DataArts Studio. A CDM cluster can provide an agent for DataArts Studio to communicate with non-fully-managed services. Therefore, you need to select a CDM cluster when creating an MRS data connection. If no CDM cluster is available, create one through the DataArts Migration incremental package. As a network proxy, the CDM cluster must be able to communicate with the MRS cluster. To ensure network connectivity, the CDM cluster must be in the same region, AZ, VPC, and subnet as the MRS cluster. The security group rule must also allow the CDM cluster communicate with the MRS cluster.

**Table 11** MRS Presto data connection
Parameter	Mandatory	Description
Data Connection Name	Yes	The name of the data connection to create. Data connection names can contain 1 to 50 characters. They can include only letters, numbers, underscores (_), and hyphens (-).
Tag	No	The attribute of the data connection to create. Tags make management easier. You can set a tag or select a tag created in Tags from the drop-down list. NOTE: The name of the tag. Only letters, numbers, and underscores (_) are allowed. Tag names cannot start with underscores (_). Enter up to 100 characters.
Cluster Name	Yes	The name of the MRS cluster. Select an MRS cluster that Hive belongs to. Only MRS clusters are supported. A Hadoop cluster can be selected only after it is managed by MRS. All the MRS clusters with the same project ID and enterprise project are displayed. If the connection fails after you select a cluster, check whether the MRS cluster can communicate with the CDM instance which functions as the agent. They can communicate with each other in the following scenarios: If the CDM cluster in the DataArts Studio instance and the MRS cluster are in different regions, a public network or a dedicated connection is required. If the Internet is used for communication, ensure that an EIP has been bound to the CDM cluster, and the MRS cluster can access the Internet and the port has been enabled in the firewall rule. If the CDM cluster in the DataArts Studio instance and the MRS cluster are in the same region, VPC, subnet, and security group, they can communicate with each other by default. If they are in the same VPC but in different subnets or security groups, you must configure routing rules and security group rules. For details about how to configure routing rules, see configuring routes. For details about how to configure security group rules, see configuring security group rules. The MRS cluster and the DataArts Studio workspace belong to the same enterprise project. If they do not, you can modify the enterprise project of the workspace.
Description	No	You can enter the description of the connection.

**Table 12** Host Connection
Parameter	Mandatory	Description
Data Connection Name	Yes	Name of the host connection. The value can contain only letters, digits, hyphens (-), and underscores (_).
Tag	No	The attribute of the data connection to create. Tags make management easier. You can set a tag or select a tag created in Tags from the drop-down list. NOTE: The tag name can contain letters, digits, and underscores (_), and cannot start with underscores (_). It can contain up to 100 characters.
Host Address	Yes	IP address of the Linux host For details, see Viewing Details About an ECS.
Agent	Yes	Agents provided by the CDM cluster, which is required if Proxy connection is selected for Connection Type.
Port	Yes	SSH port number of the host
Username	Yes	Username of the host
Login Mode	Yes	Mode for logging in to the host Key pair Password
Key Pair	Yes	If you select Key pair for Login Mode, you need to obtain the private key file, upload it to OBS, and select the OBS path. This parameter is available only when Login Mode is set to Key pair. NOTE: The uploaded private key file must be in PEM format, and the uploaded private key file and the public key configured on the host must be in the same key pair.
Key Pair Password	No	If no password is set for the key pair, you do not need to set this parameter.
Password	Yes	Password for logging in to the host.
KMS Key	Yes	Key created on Key Management Service (KMS) and used for encrypting and decrypting user passwords and key pairs. You can select a created key from KMS.
Host Connection Description	No	Description of the host connection

Creating a Kerberos Authentication User for an MRS Security Cluster

You cannot create a data connection for an MRS security cluster as user admin. User admin is the management page user by default and cannot be used as the authentication user of a security cluster. To create an MRS user, perform the following steps:

For clusters of MRS 3.x:

Log in to MRS Manager as user admin.
Choose System > Permission > User. On the page displayed, click Create to add a dedicated user as the Kerberos authentication user. Select the user group superGroup for the user, and assign all roles to the user.
- For clusters of MRS 3.1.0 or later, the user must at least have permissions of the Manager_viewer role to create data connections in Management Center. To perform database, table, and data operations on components, the user must also have user group permissions of the components.
- For clusters earlier than MRS 3.1.0, the user must have permissions of the Manager_administrator or System_administrator role to create data connections in Management Center.
- A user with only the Manager_tenant or Manager_auditor permission cannot create connections.
Log in to Manager as the new user and change the initial password. Otherwise, the connection fails to be created.
Synchronize IAM users.
1. Log in to the MRS management console.
2. Choose Clusters > Active Clusters, select a running cluster, and click its name to go to its details page.
3. In the Basic Information area of the Dashboard page, click Synchronize on the right side of IAM User Sync to synchronize IAM users.
  - When the policy of the user group to which the IAM user belongs changes from MRS ReadOnlyAccess to MRS CommonOperations, MRS FullAccess, or MRS Administrator, wait for 5 minutes until the new policy takes effect after the synchronization is complete because the SSSD (System Security Services Daemon) cache of cluster nodes needs time to be updated. Then, submit a job. Otherwise, the job may fail to be submitted.
  - When the policy of the user group to which the IAM user belongs changes from MRS CommonOperations, MRS FullAccess, or MRS Administrator to MRS ReadOnlyAccess, wait for 5 minutes until the new policy takes effect after the synchronization is complete because the SSSD cache of cluster nodes needs time to be updated.

For clusters of MRS 2.x or earlier:

Log in to MRS Manager as user admin.
Choose System > Manage User. On the page displayed, add a dedicated user as the Kerberos authentication user. Select the user group superGroup for the user, and assign all roles to the user.
- For clusters of MRS 2.x or earlier, the user must have permissions of the Manager_administrator or System_administrator role to create data connections in Management Center.
- A user with only the Manager_tenant or Manager_auditor permission cannot create connections.
Log in to MRS Manager as the new user and change the initial password. Otherwise, the connection fails to be created.
Synchronize IAM users.
1. Log in to the MRS management console.
2. Choose Clusters > Active Clusters, select a running cluster, and click its name to go to its details page.
3. In the Basic Information area of the Dashboard page, click Synchronize on the right side of IAM User Sync to synchronize IAM users.
  - When the policy of the user group to which the IAM user belongs changes from MRS ReadOnlyAccess to MRS CommonOperations, MRS FullAccess, or MRS Administrator, wait for 5 minutes until the new policy takes effect after the synchronization is complete because the SSSD (System Security Services Daemon) cache of cluster nodes needs time to be updated. Then, submit a job. Otherwise, the job may fail to be submitted.
  - When the policy of the user group to which the IAM user belongs changes from MRS CommonOperations, MRS FullAccess, or MRS Administrator to MRS ReadOnlyAccess, wait for 5 minutes until the new policy takes effect after the synchronization is complete because the SSSD cache of cluster nodes needs time to be updated.

Editing a Data Connection

Log in to Management Center and click Data Connection Management.
In the data connection list, locate the data connection you want to edit and click Edit in the Operation column.
In the Edit Data Connection dialog box, modify connection parameters as required. For parameter details, see Data Connection Parameter Description.
Click Test to test whether the data connection is valid. If the connection is normal, click Yes.
If the test connection is invalid, the data connection cannot be created. Modify the connection parameters as prompted and try again.

Deleting a Data Connection

If a data connection is deleted, the data table information of the data connection will also be deleted. Exercise caution when performing this operation. If the data connection you want to delete has been referenced, it cannot be deleted.

Log in to Management Center and click Data Connection Management.
In the data connection list, locate the data connection you want to delete and click Delete in the Operation column.
In the dialog box displayed, confirm the data connection information, and click Yes.