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Tair (Redis® OSS-Compatible):Apply for a public endpoint for an instance

Last Updated:Mar 28, 2026

By default, Tair (Redis OSS-compatible) assigns only a Virtual Private Cloud (VPC) endpoint to each instance. To connect from outside a VPC—such as from a local development machine or an application not hosted on Alibaba Cloud—apply for a public endpoint first.

Warning

Public endpoints may expose your instance to security risks. Proceed with caution. To accelerate and secure data transmission, migrate your application to an Elastic Compute Service (ECS) instance in the same region and VPC as your Tair instance to connect over VPC.

Limitations

  • Cloud-native cluster instances in direct connection mode do not support public endpoints. To use a public endpoint with this instance type, see Why can't I find the option to apply for a public endpoint? in the FAQ.

  • Password-free access is only available over VPC. When connecting over a public endpoint, you must provide a password even if password-free access is enabled on the instance.

How it works

Each Tair instance has a total bandwidth shared across all connection types. Public and VPC connections draw from the same pool.

Example: An instance with 96 Mbit/s total bandwidth is already using 70 Mbit/s over VPC connections. Public endpoint connections are limited to the remaining 26 Mbit/s.

Billing

Applying for a public endpoint is free. Traffic over public endpoints is also free.

Prerequisites

Before you begin, make sure that:

  • A whitelist is configured for the instance. If no whitelist exists, the Connection Information section does not display a VPC endpoint, and the Apply for Endpoint button is unavailable. To configure a whitelist, see

  • The instance is not a cloud-native cluster instance in direct connection mode. This instance type does not support public endpoints

Procedure

  1. Log on to the console and go to the Instances page. In the top navigation bar, select the region in which the instance that you want to manage resides. Then, find the instance and click the instance ID.

  2. In the Connection Information section, click Apply for Endpoint to the right of Internet Access.

    Note

    If the instance is a cloud-native cluster instance in direct connection mode, the Apply for Endpoint button is not displayed or is dimmed.

  3. In the panel that appears, enter an endpoint and a port number.

    Parameter

    Description

    Endpoint

    • You can modify only the prefix of the endpoint. By default, the prefix is the instance ID.

    • The prefix must be 8 to 40 characters in length and can contain lowercase letters and digits. It must start with a lowercase letter.

    Port

    When you modify the endpoint, you can also modify the port number. Valid values for this parameter: 1024 to 65535.

  4. Click OK.

    After the application is submitted, the public endpoint is displayed in the Connection Information section.

API reference

API operationDescription
AllocateInstancePublicConnectionApplies for a public endpoint for an instance.

FAQ

Why can't I find the option to apply for a public endpoint?

Two situations prevent the Apply for Endpoint button from appearing:

  • No whitelist configured. If the Connection Information section does not show a VPC endpoint, the instance has no whitelist. Configure a whitelist first.

  • Direct connection mode. Cloud-native cluster instances in direct connection mode do not support public endpoints. If your application is outside the instance's VPC and you need public access, switch the instance to proxy mode. A direct-connection cloud-native cluster cannot switch modes in place—use the instance restoration feature to restore a backup to a new instance and select Proxy as the connection mode. For details, see Restore data from a backup set to a new instance. To check whether an instance runs in direct connection mode, see How do I know whether an instance is a cloud-native cluster instance that runs in direct connection mode?

    Warning

    After the new instance is created, update your connection code to use the new endpoint and connection mode. Failing to do so prevents connections to the new instance.

Is there a charge for a public endpoint?

No. Applying for a public endpoint is free, and traffic over public endpoints is not billed.

Can I use password-free access over a public endpoint?

No. Password-free access works only over VPC. When connecting over a public endpoint, authenticate with a password.

What does the "Current engine version does not support operations" error mean?

The instance is running an outdated minor engine version. Update to a supported version and try again. See Update the minor version of an instance.

What to do next

Use a public endpoint to connect to an instance