Connection failures to an ApsaraDB RDS for PostgreSQL instance often result from network configuration problems. The self-service diagnostics feature tests connectivity between the connection initiator and the RDS instance, identifies common causes of failure such as missing IP address whitelist entries, and works for both Internet and internal network connections.
How it works
The diagnostics feature checks whether the connection initiator can reach the RDS instance. A common failure cause is that the IP address of the connection initiator is not in the IP address whitelist of the RDS instance. Whitelist detection supports CIDR block matching. If an IP address falls within a CIDR block in the instance whitelist, it passes detection.
VPC connectivity requirement
If the RDS instance is deployed in a virtual private cloud (VPC), only Elastic Compute Service (ECS) instances in the same VPC can connect over an internal network. ECS instances in a different VPC cannot connect, even if the ECS IP address is in the whitelist of the RDS instance. To enable internal network communication between two VPCs, create a VPC peering connection.
Run a connectivity test
Log on to the ApsaraDB RDS console and go to the Instances page. In the top navigation bar, select the region where the RDS instance resides. Find the RDS instance and click the instance ID.
In the left-side navigation pane, click Database Connection.
In the Connection Troubleshooting section, add the IP address to test.
Internal network connection Click the Intranet Troubleshooting tab, and then click Add intranet ECS IP. In the dialog box, select the ECS instance, add it to the Selected ECS instances section, and then click OK.
Internet connection Click the Extranet Troubleshooting tab, and then click Add Extranet IP. In the dialog box, enter the public IP address, or click Load Local Public IP Address (If there is a network proxy on your PC, please turn it off first). to auto-fill the address. Then, click OK.
NoteOne-click IP address detection works only when the network proxy is disabled on the computer.
Click Start Check.
View the diagnostic results and take the appropriate action.
Status
Action
OK
No action required.
IP is not in the instance whitelist
Click Configure Whitelist in the Action column to add the IP address to the whitelist. For more information, see Configure an IP address whitelist for an ApsaraDB RDS for PostgreSQL instance.
Abnormal
Click Submit Ticket in the Action column to submit a ticket for further assistance.