This page gives an overview of multiple VPC networking for Memorystore for Redis Cluster. In situations where you only need one VPC network, we recommend (but don't require) using a service connection policy to provision your network, as explained in Networking overview.
Setting up networking for multiple VPC networks requires Memorystore users to configure and register up Private Service Connect connections.
For a tutorial on setting up multiple VPCs using only user-registered connections, see Provision a new instance to use multiple VPC networks.
For a tutorial on setting up multiple VPCs for instances provisioned with automatically registered connections, see Configure an existing instance to use multiple VPC networks.
Private Service Connect connections
This section explains essential information about Private Service Connect connections for Memorystore.
Private Service Connect connection basics
For Memorystore, a Private Service Connect connection consists of two fundamental items:
- An IP address
- An established connection between a Private Service Connect endpoint and a Memorystore instance's service attachment
Private Service Connect connection types
When using Memorystore for Redis Cluster, Private Service Connect connections fall into two categories: automatically registered and user-registered. A Memorystore for Redis Cluster instance is compatible with both types.
User-registered Private Service Connect connections: These are self-created and self-registered connections. For Memorystore, user-registered connections are needed for multiple VPC networking setups.
Self-managing these connections has the benefit of giving you control over the subnets, IP addresses, and forwarding rules used to create them. For these connections, you are responsible for their lifecycle (including creating, registering, and deleting them).
Automatically registered Private Service Connect connections: These are connections created and registered by Private Service Connect service connectivity automation for your Memorystore instance. When you create or delete a Memorystore instance, your service connection policy manages the lifecycle of the associated connection by creating, registering, or deleting the connection automatically.
If you already have a Memorystore instance that you've been using, and you want to connect additional VPC networks, you probably have automatically registered connections. If you want to keep these connections because your existing application uses them, you can keep them and only add user-registered connections for new VPCs.
Application connection requirements
To connect your application using a multiple VPC networking setup, Memorystore has networking requirements you must meet.
Each VPC network you connect to your Memorystore instance needs to have two Private Service Connect connections (either user-registered or automatically registered). One connection is the discovery connection used for your client to establish connection to the cluster. The other connection is reserved for internal usage by the Memorystore backend.
For information about connecting your client for an instance that uses only user-registered connections, see Set up a client connection.
For information about connecting your client for an instance that uses an automatically registered connection, see Set up a client connection.
For more general information about setting up connections to services through Private Service Connect endpoints, see Access published services through endpoints.
Limitations
- You can have between 1 and 20 VPC networks connected to a single Memorystore instance, and no more than 40 Private Service Connect connections in total
- To delete a Memorystore instance connected with user-registered Private Service Connect connections, you must delete and deregister the connections first.