Merge pull request #67910 from AedinC/OSDOCS-8725

OSDOCS#8725:QE and Style Revisions of MOBB Content for Deploying the External DNS Operator on ROSA

Author: EricPonvelle

cloud_experts_tutorials/cloud-experts-external-dns.adoc

@@ -20,25 +20,27 @@ toc::[]
 
 Configuring the xref:../applications/deployments/osd-config-custom-domains-applications.adoc[Custom Domain Operator] requires a wildcard CNAME DNS record in your Amazon Route 53 hosted zone. If you do not want to use a wildcard record, you can use the `External DNS` Operator to create individual entries for routes.
 
-This tutorial guides you through deploying and configuring the External DNS Operator with a custom domain in {product-title} (ROSA).
+Use this tutorial to deploy and configure the `External DNS` Operator with a custom domain in {product-title} (ROSA).
 
 [IMPORTANT]
 ====
-The External DNS Operator does not support IRSA/STS and uses long-lived IAM credentials. This tutorial will be updated once STS is supported.
+The `External DNS` Operator does not support STS using IAM Roles for Service Accounts (IRSA) and uses long-lived Identity Access Management (IAM) credentials instead. This tutorial will be updated when the Operator supports STS.
 ====
 
 [id="cloud-experts-external-dns-prerequisites"]
 == Prerequisites
 
 * A ROSA cluster
-* You have access to the OpenShift CLI (`oc`)
-* You have access to the AWS CLI (`aws`)
-* A unique domain, such as *.apps.<company_name>.io
+* A user account with `dedicated-admin` privileges
+* The OpenShift CLI (`oc`)
+* The Amazon Web Services (AWS) CLI (`aws`)
+* A unique domain, such as `*.apps.<company_name>.io`
 * An Amazon Route 53 public hosted zone for the above domain
 
-=== Environment setup
+[id="cloud-experts-external-dns-environment-setup"]
+== Setting up your environment
 
-* Prepare the environment variables:
+. Configure the following environment variables, replacing `CLUSTER_NAME` with the name of your cluster:
 +
 [source,terminal]
 ----
@@ -49,14 +51,19 @@ $ export REGION=$(oc get infrastructure cluster -o=jsonpath="{.status.platformSt
 $ export AWS_ACCOUNT_ID=$(aws sts get-caller-identity --query Account --output text)
 $ export SCRATCH="/tmp/${CLUSTER_NAME}/external-dns"
 $ mkdir -p ${SCRATCH}
-$ echo "Cluster: ${CLUSTER_NAME}, Region: ${REGION}, AWS Account ID: ${AWS_ACCOUNT_ID}"
 ----
 <1> The custom domain.
+. Ensure all fields output correctly before moving to the next section:
++
+[source,terminal]
+----
+$ echo "Cluster: ${CLUSTER_NAME}, Region: ${REGION}, AWS Account ID: ${AWS_ACCOUNT_ID}"
+----
 
 [id="cloud-experts-external-dns-custom-domain-setup"]
-== Custom domain setup
+== Setting up your custom domain
 
-ROSA manages secondary Ingress Controllers using the Custom Domain Operator. The following procedure outlines how to deploy a secondary Ingress Controller using a custom domain.
+ROSA manages secondary Ingress Controllers using the `Custom Domain` Operator. Use the following procedure to deploy a secondary Ingress Controller using a custom domain.
 
 .Prerequisites
 
@@ -65,16 +72,15 @@ ROSA manages secondary Ingress Controllers using the Custom Domain Operator. The
 
 .Procedure
 
-. Create a new project
+. Create a new project:
 +
 [source,terminal]
 ----
 $ oc new-project external-dns-operator
 ----
 
-. Create a new TLS secret from a private key and a public certificate, where `fullchain.pem` is your full wildcard certificate chain (including any intermediaries) and `privkey.pem` is your wildcard certificate's private key.
+. Create a new TLS secret from a private key and a public certificate, where `fullchain.pem` is your full wildcard certificate chain (including any intermediaries) and `privkey.pem` is your wildcard certificate's private key:
 +
-.Example
 [source,terminal]
 ----
 $ oc -n external-dns-operator create secret tls external-dns-tls --cert=fullchain.pem --key=privkey.pem
@@ -101,13 +107,12 @@ spec:
 
 . Apply the CR:
 +
-.Example
 [source,terminal]
 ----
 $ oc apply -f external-dns-custom-domain.yaml
 ----
 
-. Verify that your custom domain Ingress Controller has been deployed and is `Ready`:
+. Verify that your custom domain Ingress Controller has been deployed and has a `Ready` status:
 +
 [source,terminal]
 ----
@@ -122,7 +127,7 @@ external-dns       xxrywp.<company_name>.cluster-01.opln.s1.openshiftapps.com  *
 ----
 
 [id="cloud-experts-external-dns-prepare-aws-account"]
-== Prepare AWS account
+== Preparing your AWS account
 
 . Retrieve the Amazon Route 53 public hosted zone ID:
 +
@@ -132,7 +137,7 @@ $ export ZONE_ID=$(aws route53 list-hosted-zones-by-name --output json \
   --dns-name "${DOMAIN}." --query 'HostedZones[0]'.Id --out text | sed 's/\/hostedzone\///')
 ----
 +
-. Create an AWS IAM Policy document that allows the External DNS Operator to update _only_ the custom domain public hosted zone:
+. Create an AWS IAM Policy document that allows the `External DNS` Operator to update _only_ the custom domain public hosted zone:
 +
 [source,terminal]
 ----
@@ -208,9 +213,9 @@ EOF
 ----
 
 [id="cloud-experts-external-dns-install-external-dns-operator"]
-== Install the External DNS Operator
+== Installing the External DNS Operator
 
-. Install the External DNS Operator from OperatorHub:
+. Install the `External DNS` Operator from OperatorHub:
 +
 [source,terminal]
 ----
@@ -238,7 +243,7 @@ spec:
 EOF
 ----
 +
-. Wait until the External DNS Operator is running:
+. Wait until the `External DNS` Operator is running:
 +
 [source,terminal]
 ----
@@ -252,7 +257,7 @@ $ oc rollout status deploy external-dns-operator --timeout=300s
 $ oc -n external-dns-operator create secret generic external-dns \
   --from-file "${SCRATCH}/credentials"
 ----
-. Deploy the ExternalDNS controller:
+. Deploy the `ExternalDNS` controller:
 +
 [source,terminal]
 ----
@@ -287,9 +292,11 @@ $ oc rollout status deploy external-dns-${DOMAIN} --timeout=300s
 ----
 
 [id="cloud-experts-external-dns-deploy-a-sample-application"]
-== Deploy a sample application
+== Deploying a sample application
 
-. Create a new project for our sample application:
+Now that the `ExternalDNS` controller is running, you can deploy a sample application to confirm that the custom domain is configured and trusted when you expose a new route.
+
+. Create a new project for your sample application:
 +
 [source,terminal]
 ----
@@ -305,8 +312,6 @@ $ oc new-app -n hello-world --image=docker.io/openshift/hello-openshift
 +
 . Create a route for the application specifying your custom domain name:
 +
-.Example
-+
 [source,terminal]
 ----
 $ oc -n hello-world create route edge --service=hello-openshift hello-openshift-tls \
@@ -324,14 +329,14 @@ It can take a few minutes for the record to appear in Amazon Route 53.
 $ aws route53 list-resource-record-sets --hosted-zone-id ${ZONE_ID} \
    --query "ResourceRecordSets[?Type == 'CNAME']" | grep hello-openshift
 ----
-. You can also view the TXT records that indicate they were created by ExternalDNS:
+. Optional: You can also view the TXT records that indicate they were created by ExternalDNS:
 +
 [source,terminal]
 ----
 $ aws route53 list-resource-record-sets --hosted-zone-id ${ZONE_ID} \
    --query "ResourceRecordSets[?Type == 'TXT']" | grep ${DOMAIN}
 ----
-. Navigate to your custom console domain in the browser where you see the OpenShift login.
+. Navigate to your custom console domain in the browser where you see the OpenShift login:
 +
 [source,terminal]
 ----