What Should I Do If an ECS Cannot Connect to a GaussDB(for MySQL) Instance?

Perform the following steps to identify the problem:

1. Check whether the ECS and GaussDB(for MySQL) instance are located in the same VPC.
   • If they are in the same VPC, go to 2.
   • If they are in different VPCs, create an ECS in the VPC where the instance is located.

2. Check whether a security group has been created for the ECS.
   • If a security group has been created, check whether its rules are appropriate.

     For details, see the security group description in "Creating an Instance" in the GaussDB(for MySQL) Getting Started. Then, go to 3.

   • If no security group has been created, go to the VPC console from the ECS details page and create a security group.

3. Check whether the ECS can connect to the instance over the instance port.

   The default port of a primary/standby instance is 3306.

   telnet <IP address> {Port number}

   • If the ECS can connect to the instance, no further action is required.
   • If the ECS still cannot connect to the instance port, contact technical support.