This topic provides the solution to an issue that may occur when you connect a bastion host to a database.
What do I do if my bastion host fails to access an ApsaraDB RDS database?
The reason for the failure may be that you did not add the egress IP address of the bastion host to the IP whitelist of the ApsaraDB RDS database. For more information about how to add the egress IP address of a bastion host to the IP whitelist of an ApsaraDB RDS database, see Configure an IP address whitelist.
To find the egress IP of your Bastionhost instance, log on to the Bastionhost console. On the instance details page, click the Egress IP tab. Then, add the IP to the whitelist of the ApsaraDB RDS instance.