Tair (Redis® OSS-Compatible):Enable direct connection

Prerequisites

Before you begin, make sure your instance meets all of the following requirements.

The instance must:

• Use the cluster architecture with Deployment Mode set to Classic

• Be compatible with Redis 5.0 and updated to the latest minor version

• Have Transport Layer Security (TLS) disabled — see TLS encryption

• Have the vSwitch with enough available IP addresses: direct connection allocates one IP address to the primary node of each shard, plus one for the endpoint itself. For an 8-shard instance, the vSwitch needs at least 9 available IP addresses. To check, see Query the number of available IP addresses for the vSwitch of an instance

The instance must not:

• Use the cloud-native cluster architecture in proxy mode — direct connection mode cannot be enabled for this configuration

For a cloud-native cluster instance already in direct connection mode, a direct connection endpoint is provided by default and does not need to be enabled.

Connection modes

Limitations

• Reduced per-shard connections: Because the proxy is bypassed, the maximum number of connections per shard drops to 10,000 (Redis Open-Source Edition cluster) or 30,000 (Tair (Enterprise Edition) cluster). If data skew occurs — where one shard is heavily accessed while others are mostly idle — connections to that shard may be exhausted, causing new connection requests to fail. To diagnose data skew caused by hot spot keys or large keys, see Top Key statistics and Offline full key analysis.

• Major version upgrades and zone changes blocked: After enabling direct connection mode, you cannot upgrade the major version or change the zone of the instance. Release the private endpoint first, then perform the upgrade or zone change. See Upgrade the major version, Migrate an instance across zones, and Release a private endpoint.

• Configuration changes limited: When changing the configuration of an instance with direct connection enabled, change only the number of shards or shard specifications, and only one at a time. See Why am I unable to change the configurations of a classic (local disk-based) cluster instance?

Enable direct connection

Enabling direct connection does not interrupt your service.

1. Log on to the console and go to the Instances page. In the top navigation bar, select the region of the instance. Find the instance and click its ID.

2. In the Connection Information section, click Apply for Endpoint next to Private Endpoint.

3. In the panel that appears, configure the endpoint and port.

   Configuration	Description
   Endpoint	Only the prefix can be modified. The default prefix is the instance ID. A custom prefix must start with a lowercase letter and contain only lowercase letters and digits, 8–40 characters in length.
   Port Number	Must be between 1024 and 65535. You can change the port number when you modify the endpoint.

4. Click OK.

For a connection example, see Connect to an instance in direct connection mode.

FAQ

I meet all the prerequisites, but I cannot find the Apply for Endpoint button. What should I do?

Update the instance to the latest minor version. See Update the minor version and proxy version.

Can I use the direct connection endpoint and the proxy endpoint at the same time?

For a classic cluster architecture, yes — both modes can be active simultaneously. For a cloud-native cluster architecture, only one mode can be active at a time.

API reference

What's next

• Release a private endpoint (optional)