Tair (Redis® OSS-Compatible):How do I troubleshoot connection issues in Tair?

Before you connect to a Tair or Redis Open-Source Edition instance, check the network environment of your client. The following figure shows the procedure.

Procedure:

1. Check the network environment of your client.

   • VPC: If the client is hosted on an Elastic Compute Service (ECS) instance that resides in a virtual private cloud (VPC), make sure that the ECS instance and the Tair instance to which you want to connect reside in the same VPC.

     • If the ECS instance and the Tair instance reside in the same VPC, the client can connect to the Tair instance over the VPC.

     • If the ECS instance resides in a different VPC than the Tair instance, the ECS instance and the Tair instance may reside in different regions or belong to different Alibaba Cloud accounts.

   • Internet.

2. Obtain the endpoint that is used to connect to the Tair instance. For more information, see View endpoints.

   Make sure that you obtain the correct endpoint for your instance. If you plan to connect to the Tair instance over the Internet but you obtain the VPC endpoint, the connection cannot be established.

3. Prepare to establish a connection.

Follow the instructions shown in the following figure to troubleshoot connection settings.

Procedure:

1. Check whether the IP address or CIDR block of your client is added to a whitelist of the Tair instance. For more information, see Configure whitelists.

2. Run the PING command to test whether the network connection between the ECS instance and the Tair instance is normal. For more information, see Run the PING command to check the connection between an ECS instance and a Tair instance.

3. Check whether the credentials that you use to connect to the Tair instance are valid. For more information, see Connect to an instance.

4. If you cannot connect to the Tair instance after you troubleshoot the preceding issues, check the logs and error codes of the client. For more information, see Common errors and troubleshooting.

If connection issues occur during the runtime of the Tair instance, follow the instructions shown in the following figure for troubleshooting.

Procedure:

1. Check whether the Tair instance is undergoing a master-replica switchover. For more information, see Master-replica switchovers.

   During a master-replica switchover, it is normal for the instance to experience transient connections that last for a few seconds. The connection will automatically recover without human intervention.

2. Perform diagnostics on the instance. For more information about how to interpret diagnostic reports, see Analyze a diagnostic report.