Connectivity

Private network connectivity for namespaces

Temporal Cloud supports private connectivity to Namespaces via AWS PrivateLink or GCP Private Service Connect, in addition to the default public internet endpoints.

Namespace access is always securely authenticated via API keys or mTLS, regardless of how you choose to connect.

For information about IP address stability and allowlisting, see IP addresses.

Required steps

Setting up private connectivity is a three-step process — and it's important to understand that private connectivity (the network path) and Connectivity Rules (Temporal's enforcement layer) are related but separate concepts:

1. Set up the private connection from your VPC to the region where your Temporal Namespace is located.
2. Update your private DNS and/or client configuration to actually use the private connection. Activating private connectivity does not change your Namespace Endpoint or Regional Endpoint automatically — clients keep resolving the public addresses until you do this step.
3. (GCP PSC: required. AWS PrivateLink: optional.) Create a Connectivity Rule for the private connection and attach it to the target Namespace(s). This blocks all access to the Namespace that does not arrive over a configured connection. You can mix private and public rules to also allow internet connectivity.

For steps 1 and 2, follow the guide for your Namespace's cloud provider:

• AWS PrivateLink creation and private DNS setup
• Google Cloud Private Service Connect creation and private DNS setup

Finish client setup (complete step 2)

After creating a private connection, you must set up private DNS or update the configuration of all clients you want to use the private connection.

We recommend using private DNS.

Without this step, your clients may connect to the Namespace over the internet if they were previously using public connectivity, or they will not be able to connect at all.

If that's not an option for you, refer to our guide for updating the server and TLS settings on your clients.

For step 3, keep reading for details on Connectivity Rules.

Connectivity rules

Web UI Connectivity

The Temporal Cloud Web UI is not currently subject to connectivity rule enforcement. Even if a namespace is configured with private connectivity rules, the Web UI for that namespace remains accessible over the public internet.

Definition

Connectivity Rules are Temporal Cloud's mechanism for restricting the network paths that can reach a Namespace. They are enforced by Temporal Cloud — they do not create or modify the underlying network connection.

By default, a Namespace has zero Connectivity Rules and is reachable over (1) the public internet and (2) any private connections you've already configured to the region containing the Namespace. Namespace access is always securely authenticated via API keys or mTLS, regardless of Connectivity Rules.

When you attach one or more Connectivity Rules to a Namespace, Temporal Cloud immediately blocks any traffic that does not match a rule on that Namespace. A Namespace can have multiple Connectivity Rules, and you can mix public and private rules.

Each Connectivity Rule specifies either generic public (internet) access or a specific private connection.

When you need a Connectivity Rule

Provider	Connectivity Rule for private access	Why
AWS PrivateLink	Optional. Add one only if you want to enforce private-only access (block internet traffic to that Namespace).	AWS PrivateLink connections become usable as soon as the VPC endpoint is Available. Adding a Connectivity Rule restricts access; it does not establish it.
GCP Private Service Connect	Required. The PSC endpoint stays in Pending until a matching Connectivity Rule is created.	The Connectivity Rule is what tells Temporal Cloud to accept the PSC connection.

A public Connectivity Rule takes no parameters.

An AWS PrivateLink (PL) private Connectivity Rule requires:

• connection-id: The VPC endpoint identifier of the PL connection — the vpce-… value from your AWS account, not the endpoint service or DNS name (ex: vpce-00939a7ed9EXAMPLE).
• region: The region of the PL connection, prefixed with aws- (ex: aws-us-east-1). Must be the same region as the Namespace. Refer to the Temporal Cloud region list for supported regions.

A GCP Private Service Connect (PSC) private Connectivity Rule requires:

• connection-id: The PSC connection identifier of the endpoint (ex: 1234567890123456789). Find it on the endpoint's detail page in the Google Cloud console.
• region: The region of the PSC connection, prefixed with gcp- (ex: gcp-us-east1). Must be the same region as the Namespace. Refer to the Temporal Cloud region list for supported regions.
• gcp-project-id: The identifier of the GCP project where you created the PSC connection (ex: my-example-project-123).

Connectivity Rules can be created and managed with tcld, Terraform, the Web UI (under Connectivity in your account settings), or the Cloud Ops API.

Connectivity Rules give Temporal visibility into your private connections

Without a Connectivity Rule, Temporal Cloud has no record that your PrivateLink or PSC endpoint exists. If you open a support ticket about a private-connectivity issue, having a Connectivity Rule attached to the affected Namespace lets us correlate the connection on our side and is the fastest path to debugging.

Permissions and limits

Only Account Admins and Account Owners can create and manage connectivity rules. Connectivity rules are visible to Account Developers, Account Admins, and Account Owners.

By default each namespace is limited to 5 private connectivity rules, and each account is limited to 50 private connectivity rules. You can contact support to request a higher limit.

There is only one public rule allowed per account, because it's generic and can be reused for all namespaces that you want to be available on the internet. Trying to create more than one public rule will throw an error.

Creating a connectivity rule

Temporal Cloud CLI (tcld)

Create private connectivity rule (AWS):

tcld connectivity-rule create --connectivity-type private --connection-id "vpce-abcde" --region "aws-us-east-1"

Create private connectivity rule (GCP):

tcld connectivity-rule create --connectivity-type private --connection-id "1234567890" --region "gcp-us-central1" --gcp-project-id "my-project-123"

Create public connectivity rule (you only need to do this once ever in your account):

tcld connectivity-rule create --connectivity-type public

The cr alias works the same way:

Private connectivity rule:

tcld cr create --connectivity-type private --connection-id "vpce-abcde" --region "aws-us-east-1"

tcld cr create --connectivity-type public

Terraform

Examples in the Terraform repo

Attach connectivity rules to a namespace

Be careful! When any connectivity rules are set on a namespace, that namespace is ONLY accessible via the connections defined in those rules. If you remove a connectivity rule that your workers are using, your traffic will be interrupted.

If you already have workers using a namespace, adding both a public rule and any private rules simultaneously can help you avoid unintended loss of access. You can then ensure all workers are using private connections, and then remove the public rule.

Temporal Cloud CLI (tcld)

Setting the connectivity rules on a namespace:

tcld namespace set-connectivity-rules --namespace "my-namespace.abc123" --connectivity-rule-ids "rule-id-1" --connectivity-rule-ids "rule-id-2"

Or using aliases:

tcld n scrs -n "my-namespace.abc123" --ids "rule-id-1" --ids "rule-id-2"

Connectivity rules are attached as a set, so if rules rule-a, rule-b, and rule-c were attached to a namespace and you wanted to detach rule-c only, you'd make one call attaching both rule-a and rule-b:

tcld namespace set-connectivity-rules --namespace "my-namespace.abc123 --ids rule-a --ids rule-b

Remove all connectivity rules (this will make the namespace public):

tcld namespace set-connectivity-rules --namespace "my-namespace.abc123" --remove-all

Terraform

Example in the Terraform repo

View the connectivity rules for a namespace

You have two ways to view the connectivity rules attached to a particular namespace.

Get namespace

Connectivity rules are included in the namespace details returned by the namespace get command.

tcld namespace get -n "my-namespace.abc123"

List connectivity rules by namespace

To see only the connectivity rules for a specific namespace (without other namespace details), use the connectivity-rule list command with a namespace argument.

tcld connectivity-rule list -n "my-namespace.abc123"

Update DNS or clients to use private connectivity

We strongly recommend using private DNS instead of updating client server and TLS settings:

• How to set up private DNS in AWS
• How to set up private DNS in GCP

If you are unable to configure private DNS, you must update two settings in your Temporal clients:

1. Set the endpoint server address to the PrivateLink or Private Service Connect endpoint (e.g. vpce-0123456789abcdef-abc.us-east-1.vpce.amazonaws.com:7233 or <GCP PSC IP address>:7233).
2. Set TLS configuration to override the TLS server name (the Namespace Endpoint, e.g., my-namespace.my-account.tmprl.cloud).

The TLS server name override depends on your authentication method:

Authentication	TLS server name to use
mTLS (single-region Namespace)	The Namespace Endpoint, e.g. my-namespace.my-account.tmprl.cloud
API key (single-region Namespace)	The regional API endpoint, e.g. us-east-1.aws.api.temporal.io or us-central1.gcp.api.temporal.io
Multi-region Namespace (mTLS or API key)	The active region endpoint, e.g. aws-us-east-1.region.tmprl.cloud

If you authenticate with an API key over PrivateLink/PSC and use the wrong server name, the TLS handshake will fail with errors such as connection reset by peer even though nc reports the port as open.

Updating these settings depends on the client you're using.

temporal CLI

TEMPORAL_ADDRESS=vpce-0123456789abcdef-abc.us-east-1.vpce.amazonaws.com:7233
TEMPORAL_NAMESPACE=my-namespace.my-account
TEMPORAL_TLS_CERT=<path/to/cert.pem>
TEMPORAL_TLS_KEY=<path/to/cert.key>
TEMPORAL_TLS_SERVER_NAME=my-namespace.my-account.tmprl.cloud

temporal workflow count -n $TEMPORAL_NAMESPACE

grpcurl

grpcurl \
    -servername my-namespace.my-account.tmprl.cloud \
    -cert path/to/cert.pem \
    -key path/to/cert.key \
    vpce-0123456789abcdef-abc.us-east-1.vpce.amazonaws.com:7233 \
    temporal.api.workflowservice.v1.WorkflowService/GetSystemInfo

Temporal SDKs

Go

c, err := client.Dial(client.Options{
	HostPort:  "vpce-0123456789abcdef-abc.us-east-1.vpce.amazonaws.com:7233",
	Namespace: "namespace-name.accId",
	ConnectionOptions: client.ConnectionOptions{
		TLS: &tls.Config{
			Certificates: []tls.Certificate{cert},
			ServerName:   "my-namespace.my-account.tmprl.cloud",
		},
	},
})

Java

WorkflowServiceStubs service =
        WorkflowServiceStubs.newServiceStubs(
            WorkflowServiceStubsOptions.newBuilder()
                .setSslContext(sslContext)
                .setTarget("vpce-0123456789abcdef-abc.us-east-1.vpce.amazonaws.com:7233")
                .setChannelInitializer(
                    c -> c.overrideAuthority("my-namespace.my-account.tmprl.cloud"))
                .build());

Python

client_config["tls"] = TLSConfig(
    client_cert=bytes(crt, "utf-8"),
    client_private_key=bytes(key, "utf-8"),
    domain="my-namespace.my-account.tmprl.cloud",
)

client = await Client.connect("vpce-0123456789abcdef-abc.us-east-1.vpce.amazonaws.com:7233")

TypeScript

const connection = await NativeConnection.connect({
  address: "vpce-0123456789abcdef-abc.us-east-1.vpce.amazonaws.com:7233",
  tls: {
    serverNameOverride: "my-namespace.my-account.tmprl.cloud",
    //serverRootCACertificate,
    // See docs for other TLS options
    clientCertPair: {
      crt: fs.readFileSync(clientCertPath),
      key: fs.readFileSync(clientKeyPath),
    },
  },
});

PHP

PHP example coming soon.

.NET

// Create client 
var client = await TemporalClient.ConnectAsync(
  new(ctx.ParseResult.GetValueForOption(targetHostOption)!)
  {
    Namespace = ctx.ParseResult.GetValueForOption (namespaceOption)!,
    // Set TLS options with client certs. Note, more options could 
    // be added here for server CA (i.e. "ServerRootCACert") or SNI 
    // override (i.e. "Domain") for self-hosted environments with 
    // self-signed certificates. 
    Tls = new() 
    {
      ClientCert = 
        await File.ReadAllBytesAsync(ctx.ParseResult.GetValueForOption(clientCertOption) !.FullName), 
      ClientPrivateKey = 
        await File.ReadAllBytesAsync(ctx.ParseResult.GetValueFor0ption(clientKey0ption)!.FullName), Domain = "my-namespace.my-account.tmprl.cloud",
  },
});

// dotnet run --target-host "vpce-0123456789abcdef-abc.us-east-1.vpce.amazonaws.com:7233"

Ruby

Ruby example coming soon.

To check whether your client has network connectivity to the private endpoint in question, run:

nc -zv vpce-0123456789abcdef-abc.us-east-1.vpce.amazonaws.com 7233

Control plane connectivity

Using the Temporal Cloud web UI, Terraform provider, tcld CLI, or Cloud Ops APIs requires network access to the Temporal Cloud control plane.

Control plane hostnames

Different hostnames are used for different parts of the service.

• saas-api.tmprl.cloud (required for Terraform, tcld, and Cloud Ops APIs)
• web.onboarding.tmprl.cloud (required for Web UI)
• web.saas-api.tmprl.cloud (required for Web UI)

AWS PrivateLink connectivity to Temporal Cloud control plane

Temporal Cloud supports AWS PrivateLink connections to the control plane, which allows access from applications running in VPCs that cannot egress to the public internet. Temporal Cloud does not support restricting an account so that private connectivity is the sole connectivity method to the control plane; the control plane is always accessible via public internet.

Control plane access is always securely authenticated via API keys or JWT tokens, regardless of how you choose to connect.

To set up a PrivateLink connection to the Temporal Cloud control plane, follow these instructions, but use the control plane endpoint information below:

Hostname	Region	Control Plane PrivateLink Service Name
saas-api.tmprl.cloud	us-west-2	com.amazonaws.vpce.us-west-2.vpce-svc-0c57a5930b6f6be0e

The control plane PrivateLink endpoint includes a private DNS name, which lets your clients use the PrivateLink connection without having to set up private DNS or having to override client configuration. To use the DNS name, make sure your VPC has the Enable DNS hostnames and Enable DNS support options enabled. If you cannot use the DNS name, you can also manually set up private DNS or override the server and TLS settings on your clients.

Finish client setup

After creating a private connection, you must use the provided DNS name, set up private DNS, or update the configuration of all clients you want to use the private connection.

Without this step, your clients may connect to the control plane over the internet if they were previously using public connectivity, or they will not be able to connect at all.

The control plane is also accessible via the PrivateLink endpoint in AWS us-west-2 that can be used for namespace traffic, but we strongly recommend using the control-plane specific endpoint for control plane traffic.