Configuring TLS and mTLS on the Istio ingress

This topic explains how to enable on-way TLS and mTLS on the Istio ingress.

Configuring one-way TLS

Use one-way TLS to secure API proxy endpoints on the Istio ingress. To enable one-way TLS, you configure the ingress with TLS cert/key pairs or with a Kubernetes Secret, as explained in the following options.

Option 1: key/cert pair

Provide SSL cert and key files in the virtualhosts property in your overrides file:

virtualhosts:
  - name: $ENVIRONMENT_GROUP_NAME
    sslCertPath: "$CERT_FILE"
    sslKeyPath: "$KEY_FILE"

Where $ENVIRONMENT_GROUP_NAME is the name of an environment group with corresponding host aliases, and $CERT_FILE and $KEY_FILE are TLS key and certificate files. See Create TLS certificates.

Option 2: Kubernetes Secret

Create a Kubernetes Secret in the istio-system namespace and add the Secret name to your overrides file:

Create the Secret:

kubectl create -n istio-system secret generic $SECRET_NAME  \
--from-file=key=$KEY_FILE \
--from-file=cert=$CERT_FILE

Configure the virtualhosts property in your overrides file:

virtualhosts:
  - name: $ENVIRONMENT_GROUP_NAME
    tlsMode: SIMPLE  # Note: SIMPLE is the default, so it is optional.
    sslSecret: $SECRET_NAME

Configuring mTLS

Instead of one-way TLS, you can configure mTLS on the Istio ingress. There are two options for configuring mTLS, as explained below.

Option 1: key/cert pair and CA file

Provide a Certificate Authority (CA) certificate with SSL cert and key files in the virtualhosts property in your overrides file:

virtualhosts:
  - name: $ENVIRONMENT_GROUP_NAME
    tlsMode: MUTUAL
    caCertPath: "$CA_FILE"
    sslCertPath: "$CERT_FILE"
    sslKeyPath: "$KEY_FILE"

Where $ENVIRONMENT_GROUP_NAME is the name of an environment group with corresponding host aliases, $CA_FILE is an authorized certificate, and $CERT_FILE and $KEY_FILE are TLS key and certificate files. See Create TLS certificates.

Option 2: Kubernetes Secrets

Create two Kubernetes secrets in the istio-system namespace. The first secret is for the CA and the second is for the SSL cert/key pair. Then, add them to your overrides file.

Create two Kubernetes secrets in the istio-system namespace. The first secret is for the CA and the second is for the SSL cert/key pair:
```
kubectl create -n istio-system secret generic $SECRET_NAME  \
--from-file=key=$KEY_FILE \
--from-file=cert=$CERT_FILE
```

Create a secret for the CA:

kubectl create -n istio-system secret generic $SECRET_NAME-cacert  \
--from-file=cacert=$CA_FILE

Configure the virtualhosts property in your overrides file:

virtualhosts:
  - name: $ENVIRONMENT_GROUP_NAME
    tlsMode: MUTUAL  # Note: Be sure to specify MUTUAL
    sslSecret: $SECRET_NAME