open-consul/website/content/docs/connect/config-entries/terminating-gateway.mdx

---
layout: docs
page_title: Terminating Gateway - Configuration Entry Reference
description: >-
  The terminating gateway configuration entry kind defines behavior to secure outgoing communication between the service mesh and non-mesh services. Use the reference guide to learn about `""terminating-gateway""` config entry parameters and connecting from your service mesh to external or non-mesh services registered with Consul.
---

# Terminating Gateway Configuration Entry

-> **v1.8.4+:** On Kubernetes, the `TerminatingGateway` custom resource is supported in Consul versions 1.8.4+.<br />
**v1.8.0+:** On other platforms, this config entry is supported in Consul versions 1.8.0+.

The `terminating-gateway` config entry kind (`TerminatingGateway` on Kubernetes) allows you to configure terminating gateways
to proxy traffic from services in the Consul service mesh to services registered with Consul that do not have a
[Connect service sidecar proxy](/consul/docs/connect/proxies). The configuration is associated with the name of a gateway service
and will apply to all instances of the gateway with that name.

~> [Configuration entries](/consul/docs/agent/config-entries) are global in scope. A configuration entry for a gateway name applies
across all federated Consul datacenters. If terminating gateways in different Consul datacenters need to route to different
sets of services within their datacenter then the terminating gateways **must** be registered with different names.

See [Terminating Gateway](/consul/docs/connect/gateways/terminating-gateway) for more information.

## TLS Origination

By specifying a path to a [CA file](/consul/docs/connect/config-entries/terminating-gateway#cafile) connections
from the terminating gateway will be encrypted using one-way TLS authentication. If a path to a
[client certificate](/consul/docs/connect/config-entries/terminating-gateway#certfile)
and [private key](/consul/docs/connect/config-entries/terminating-gateway#keyfile) are also specified connections
from the terminating gateway will be encrypted using mutual TLS authentication.

~> Setting the `SNI` field is strongly recommended when enabling TLS to a service. If this field is not set,
Consul will not attempt to verify the Subject Alternative Name fields in the service's certificate.

If none of these are provided, Consul will **only** encrypt connections to the gateway and not
from the gateway to the destination service.

## Wildcard service specification

Terminating gateways can optionally target all services within a Consul namespace by specifying a wildcard "\*"
as the service name. Configuration options set on the wildcard act as defaults that can be overridden
by options set on a specific service name.

Note that if the wildcard specifier is used, and some services in that namespace have a Connect sidecar proxy,
traffic from the mesh to those services will be evenly load-balanced between the gateway and their sidecars.

## Sample Config Entries

### Access an external service

<Tabs>
<Tab heading="Consul OSS">

Link gateway named "us-west-gateway" with the billing service.

Connections to the external service will be unencrypted.

<CodeTabs tabs={[ "HCL", "Kubernetes YAML", "JSON" ]}>

```hcl
Kind = "terminating-gateway"
Name = "us-west-gateway"

Services = [
  {
    Name = "billing"
  }
]
```

```yaml
apiVersion: consul.hashicorp.com/v1alpha1
kind: TerminatingGateway
metadata:
  name: us-west-gateway
spec:
  services:
    - name: billing
```

```json
{
  "Kind": "terminating-gateway",
  "Name": "us-west-gateway",
  "Services": [
    {
      "Name": "billing"
    }
  ]
}
```

</CodeTabs>

</Tab>
<Tab heading="Consul Enterprise">

Link gateway named "us-west-gateway" in the default namespace with the billing service in the finance namespace.

Connections to the external service will be unencrypted.

<CodeTabs tabs={[ "HCL", "Kubernetes YAML", "JSON" ]}>

```hcl
Kind = "terminating-gateway"
Name = "us-west-gateway"
Namespace = "default"

Services = [
  {
    Namespace = "finance"
    Name      = "billing"
  }
]
```

```yaml
apiVersion: consul.hashicorp.com/v1alpha1
kind: TerminatingGateway
metadata:
  name: us-west-gateway
spec:
  services:
    - name: billing
      namespace: finance
```

```json
{
  "Kind": "terminating-gateway",
  "Name": "us-west-gateway",
  "Namespace": "default",
  "Services": [
    {
      "Namespace": "finance",
      "Name": "billing"
    }
  ]
}
```

</CodeTabs>

</Tab>
</Tabs>

### Access an external service over TLS

<Tabs>
<Tab heading="Consul OSS">

Link gateway named "us-west-gateway" with the billing service, and specify a CA
file to be used for one-way TLS authentication.

-> **Note**: When not using destinations in transparent proxy mode, you must specify the `CAFile` parameter
and point to a valid CA bundle in order to properly initiate a TLS
connection to the destination service. For more information about configuring a gateway for destinations, refer to [Register an External Service as a Destination](/consul/docs/k8s/connect/terminating-gateways#register-an-external-service-as-a-destination).

<CodeTabs tabs={[ "HCL", "Kubernetes YAML", "JSON" ]}>

```hcl
Kind = "terminating-gateway"
Name = "us-west-gateway"

Services = [
  {
    Name   = "billing"
    CAFile = "/etc/certs/ca-chain.cert.pem"
    SNI    = "billing.service.com"
  }
]
```

```yaml
apiVersion: consul.hashicorp.com/v1alpha1
kind: TerminatingGateway
metadata:
  name: us-west-gateway
spec:
  services:
    - name: billing
      caFile: /etc/certs/ca-chain.cert.pem
      sni: billing.service.com
```

```json
{
  "Kind": "terminating-gateway",
  "Name": "us-west-gateway",
  "Services": [
    {
      "Name": "billing",
      "CAFile": "/etc/certs/ca-chain.cert.pem"
      "SNI": "billing.service.com"
    }
  ]
}
```

</CodeTabs>

</Tab>
<Tab heading="Consul Enterprise">

Link gateway named "us-west-gateway" in the default namespace with the billing service in the finance namespace,
and specify a CA file to be used for one-way TLS authentication.

-> **Note**: The `CAFile` parameter must be specified _and_ point to a valid CA
bundle in order to properly initiate a TLS connection to the destination service.

<CodeTabs tabs={[ "HCL", "Kubernetes YAML", "JSON" ]}>

```hcl
Kind = "terminating-gateway"
Name = "us-west-gateway"
Namespace = "default"

Services = [
  {
    Namespace = "finance"
    Name      = "billing"
    CAFile    = "/etc/certs/ca-chain.cert.pem"
    SNI       = "billing.service.com"
  }
]
```

```yaml
apiVersion: consul.hashicorp.com/v1alpha1
kind: TerminatingGateway
metadata:
  name: us-west-gateway
spec:
  services:
    - name: billing
      namespace: finance
      caFile: /etc/certs/ca-chain.cert.pem
      sni: billing.service.com
```

```json
{
  "Kind": "terminating-gateway",
  "Name": "us-west-gateway",
  "Namespace": "default",
  "Services": [
    {
      "Namespace": "finance",
      "Name": "billing",
      "CAFile": "/etc/certs/ca-chain.cert.pem",
      "SNI": "billing.service.com"
    }
  ]
}
```

</CodeTabs>

</Tab>
</Tabs>

### Access an external service over mutual TLS

<Tabs>
<Tab heading="Consul OSS">

Link gateway named "us-west-gateway" with the billing service, and specify a CA
file, key file, and cert file to be used for mutual TLS authentication.

-> **Note**: The `CAFile` parameter must be specified _and_ point to a valid CA
bundle in order to properly initiate a TLS connection to the destination service.

<CodeTabs tabs={[ "HCL", "Kubernetes YAML", "JSON" ]}>

```hcl
Kind = "terminating-gateway"
Name = "us-west-gateway"

Services = [
  {
    Name     = "billing"
    CAFile   = "/etc/certs/ca-chain.cert.pem"
    KeyFile  = "/etc/certs/gateway.key.pem"
    CertFile = "/etc/certs/gateway.cert.pem"
    SNI      = "billing.service.com"
  }
]
```

```yaml
apiVersion: consul.hashicorp.com/v1alpha1
kind: TerminatingGateway
metadata:
  name: us-west-gateway
spec:
  services:
    - name: billing
      caFile: /etc/certs/ca-chain.cert.pem
      keyFile: /etc/certs/gateway.key.pem
      certFile: /etc/certs/gateway.cert.pem
      sni: billing.service.com
```

```json
{
  "Kind": "terminating-gateway",
  "Name": "us-west-gateway",
  "Services": [
    {
      "Name": "billing",
      "CAFile": "/etc/certs/ca-chain.cert.pem",
      "KeyFile": "/etc/certs/gateway.key.pem",
      "CertFile": "/etc/certs/gateway.cert.pem",
      "SNI": "billing.service.com"
    }
  ]
}
```

</CodeTabs>

</Tab>
<Tab heading="Consul Enterprise">

Link gateway named "us-west-gateway" in the default namespace with the billing service in the finance namespace.
Also specify a CA file, key file, and cert file to be used for mutual TLS authentication.

-> **Note**: The `CAFile` parameter must be specified _and_ point to a valid CA
bundle in order to properly initiate a TLS connection to the destination service.

<CodeTabs tabs={[ "HCL", "Kubernetes YAML", "JSON" ]}>

```hcl
Kind = "terminating-gateway"
Name = "us-west-gateway"
Namespace = "default"

Services = [
  {
    Namespace = "finance"
    Name      = "billing"
    CAFile    = "/etc/certs/ca-chain.cert.pem"
    KeyFile   = "/etc/certs/gateway.key.pem"
    CertFile  = "/etc/certs/gateway.cert.pem"
    SNI       = "billing.service.com"
  }
]
```

```yaml
apiVersion: consul.hashicorp.com/v1alpha1
kind: TerminatingGateway
metadata:
  name: us-west-gateway
spec:
  services:
    - name: billing
      namespace: finance
      caFile: /etc/certs/ca-chain.cert.pem
      keyFile: /etc/certs/gateway.key.pem
      certFile: /etc/certs/gateway.cert.pem
      sni: billing.service.com
```

```json
{
  "Kind": "terminating-gateway",
  "Name": "us-west-gateway",
  "Namespace": "default",
  "Services": [
    {
      "Namespace": "finance",
      "Name": "billing",
      "CAFile": "/etc/certs/ca-chain.cert.pem",
      "KeyFile": "/etc/certs/gateway.key.pem",
      "CertFile": "/etc/certs/gateway.cert.pem",
      "SNI": "billing.service.com"
    }
  ]
}
```

</CodeTabs>

</Tab>
</Tabs>

### Override connection parameters for a specific service

<Tabs>
<Tab heading="Consul OSS">

Link gateway named "us-west-gateway" with all services in the datacenter, and configure default certificates for mutual TLS.

Override the SNI and CA file used for connections to the billing service.

<CodeTabs tabs={[ "HCL", "Kubernetes YAML", "JSON" ]}>

<CodeBlockConfig highlight="11-15">

```hcl
Kind = "terminating-gateway"
Name = "us-west-gateway"

Services = [
  {
    Name      = "*"
    CAFile    = "/etc/common-certs/ca-chain.cert.pem"
    KeyFile   = "/etc/common-certs/gateway.key.pem"
    CertFile  = "/etc/common-certs/gateway.cert.pem"
  },
  {
    Name      = "billing"
    CAFile    = "/etc/billing-ca/ca-chain.cert.pem"
    SNI       =  "billing.service.com"
  }
]
```

</CodeBlockConfig>

<CodeBlockConfig highlight="11-13">

```yaml
apiVersion: consul.hashicorp.com/v1alpha1
kind: TerminatingGateway
metadata:
  name: us-west-gateway
spec:
  services:
    - name: '*'
      caFile: /etc/common-certs/ca-chain.cert.pem
      keyFile: /etc/common-certs/gateway.key.pem
      certFile: /etc/common-certs/gateway.cert.pem
    - name: billing
      caFile: /etc/billing-ca/ca-chain.cert.pem
      sni: billing.service.com
```

</CodeBlockConfig>

<CodeBlockConfig highlight="11-15">

```json
{
  "Kind": "terminating-gateway",
  "Name": "us-west-gateway",
  "Services": [
    {
      "Name": "*",
      "CAFile": "/etc/common-certs/ca-chain.cert.pem",
      "KeyFile": "/etc/common-certs/gateway.key.pem",
      "CertFile": "/etc/common-certs/gateway.cert.pem"
    },
    {
      "Name": "billing",
      "CAFile": "/etc/billing-ca/ca-chain.cert.pem",
      "SNI": "billing.service.com"
    }
  ]
}
```

</CodeBlockConfig>

</CodeTabs>

</Tab>
<Tab heading="Consul Enterprise">

Link gateway named "us-west-gateway" in the default namespace with all services in the finance namespace,
and configure default certificates for mutual TLS.

Override the SNI and CA file used for connections to the billing service:

<CodeTabs tabs={[ "HCL", "Kubernetes YAML", "JSON" ]}>

<CodeBlockConfig highlight="13-18">

```hcl
Kind = "terminating-gateway"
Name = "us-west-gateway"
Namespace = "default"

Services = [
  {
    Namespace = "finance"
    Name      = "*"
    CAFile    = "/etc/common-certs/ca-chain.cert.pem"
    KeyFile   = "/etc/common-certs/gateway.key.pem"
    CertFile  = "/etc/common-certs/gateway.cert.pem"
  },
  {
    Namespace = "finance"
    Name      = "billing"
    CAFile    = "/etc/billing-ca/ca-chain.cert.pem"
    SNI       =  "billing.service.com"
  }
]
```

</CodeBlockConfig>

<CodeBlockConfig highlight="12-15">

```yaml
apiVersion: consul.hashicorp.com/v1alpha1
kind: TerminatingGateway
metadata:
  name: us-west-gateway
spec:
  services:
    - name: '*'
      namespace: finance
      caFile: /etc/common-certs/ca-chain.cert.pem
      keyFile: /etc/common-certs/gateway.key.pem
      certFile: /etc/common-certs/gateway.cert.pem
    - name: billing
      namespace: finance
      caFile: /etc/billing-ca/ca-chain.cert.pem
      sni: billing.service.com
```

</CodeBlockConfig>

<CodeBlockConfig highlight="13-18">

```json
{
  "Kind": "terminating-gateway",
  "Name": "us-west-gateway",
  "Namespace": "default",
  "Services": [
    {
      "Namespace": "finance",
      "Name": "*",
      "CAFile": "/etc/common-certs/ca-chain.cert.pem",
      "KeyFile": "/etc/common-certs/gateway.key.pem",
      "CertFile": "/etc/common-certs/gateway.cert.pem"
    },
    {
      "Namespace": "finance",
      "Name": "billing",
      "CAFile": "/etc/billing-ca/ca-chain.cert.pem",
      "SNI": "billing.service.com"
    }
  ]
}
```

</CodeBlockConfig>

</CodeTabs>

</Tab>
</Tabs>

## Available Fields

<ConfigEntryReference
  keys={[
    {
      name: 'apiVersion',
      description: 'Must be set to `consul.hashicorp.com/v1alpha1`',
      hcl: false,
    },
    {
      name: 'Kind',
      description: {
        hcl: 'Must be set to `terminating-gateway`',
        yaml: 'Must be set to `TerminatingGateway`',
      },
    },
    {
      name: 'Name',
      description: 'Set to the name of the gateway being configured.',
      type: 'string: <required>',
      yaml: false,
    },
    {
      name: 'Namespace',
      type: `string: "default"`,
      enterprise: true,
      description:
        'Specifies the namespace to which the configuration entry will apply. This must match the namespace in which the gateway is registered.' +
        ' If omitted, the namespace will be inherited from [the request](/consul/api-docs/config#ns)' +
        ' or will default to the `default` namespace.',
      yaml: false,
    },
    {
      name: 'Partition',
      type: `string: "default"`,
      enterprise: true,
      description:
        'Specifies the admin partition to which the configuration entry will apply. This must match the partition in which the gateway is registered.' +
        ' If omitted, the partition will be inherited from [the request](/consul/api-docs/config)' +
        ' or will default to the `default` partition.',
      yaml: false,
    },
    {
      name: 'Meta',
      type: 'map<string|string>: nil',
      description:
        'Specifies arbitrary KV metadata pairs. Added in Consul 1.8.4.',
      yaml: false,
    },
    {
      name: 'metadata',
      children: [
        {
          name: 'name',
          description: 'Set to the name of the gateway being configured.',
        },
        {
          name: 'namespace',
          description:
            'If running Consul Open Source, the namespace is ignored (see [Kubernetes Namespaces in Consul OSS](/consul/docs/k8s/crds#consul-oss)). If running Consul Enterprise see [Kubernetes Namespaces in Consul Enterprise](/consul/docs/k8s/crds#consul-enterprise) for more details.',
        },
      ],
      hcl: false,
    },
    {
      name: 'Services',
      type: 'array<LinkedService>: <optional>',
      description: `A list of services or destinations to link
                      with the gateway. The gateway will proxy traffic to these services. These linked services
                      must be registered with Consul for the gateway to discover their addresses. They must also
                      be registered in the same Consul datacenter as the terminating gateway.
                      Destinations are an exception to this requirement, and only need to be defined as a service-defaults configuration entry in the same datacenter.
                      If Consul ACLs are enabled, the Terminating Gateway's ACL token must grant <code>service:write</code> for all linked services.`,
      children: [
        {
          name: 'Name',
          type: 'string: ""',
          description:
            'The name of the service to link with the gateway. If the wildcard specifier, `*`, is provided, then ALL services within the namespace will be linked with the gateway.',
        },
        {
          name: 'Namespace',
          enterprise: true,
          type: 'string: ""',
          description:
            'The namespace of the service. If omitted, the namespace will be inherited from the config entry.',
        },
        {
          name: 'CAFile',
          type: 'string: ""',
          description: `A file path to a PEM-encoded certificate authority.
                            The file must be present on the proxy's filesystem.
                            The certificate authority is used to verify the authenticity of the service linked with the gateway.
                            It can be provided along with a CertFile and KeyFile for mutual TLS authentication, or on its own
                            for one-way TLS authentication. If none is provided the gateway <b>will not</b> encrypt the traffic to the destination.`,
        },
        {
          name: 'CertFile',
          type: 'string: ""',
          description: {
            hcl: `A file path to a PEM-encoded certificate.
                            The file must be present on the proxy's filesystem.
                            The certificate is provided servers to verify the gateway's authenticity. It must be provided if a \`KeyFile\` was specified.`,
            yaml: `A file path to a PEM-encoded certificate.
                            The file must be present on the proxy's filesystem.
                            The certificate is provided servers to verify the gateway's authenticity. It must be provided if a \`keyFile\` was specified.`,
          },
        },
        {
          name: 'KeyFile',
          type: 'string: ""',
          description: {
            hcl: `A file path to a PEM-encoded private key.
                      The file must be present on the proxy's filesystem.
                      The key is used with the certificate to verify the gateway's authenticity. It must be provided along if a \`CertFile\` was specified.`,
            yaml: `A file path to a PEM-encoded private key.
                      The file must be present on the proxy's filesystem.
                      The key is used with the certificate to verify the gateway's authenticity. It must be provided along if a \`certFile\` was specified.`,
          },
        },
        {
          name: 'SNI',
          type: 'string: ""',
          description:
          `An optional hostname or domain name to specify during the TLS handshake. This option will also configure [strict SAN matching](https://www.envoyproxy.io/docs/envoy/latest/api-v3/extensions/transport_sockets/tls/v3/common.proto#envoy-v3-api-field-extensions-transport-sockets-tls-v3-certificatevalidationcontext-match-typed-subject-alt-names), which requires
            the external services to have certificates with SANs, not having which will result in \`CERTIFICATE_VERIFY_FAILED\` error.`,
        },
      ],
    },
  ]}
/>

## ACLs

Configuration entries may be protected by [ACLs](/consul/docs/security/acl).

Reading a `terminating-gateway` config entry requires `service:read` on the `Name`
field of the config entry.

Creating, updating, or deleting a `terminating-gateway` config entry requires
`operator:write`.