Merge pull request #173 from jiwonhu/main

Elaborate on API_SERVER_URL in agent-initiated cluster reg

docs/cluster-registration.md

@@ -73,23 +73,17 @@ CLUSTER_LABELS="--set-string labels.example=true --set-string labels.env=dev"
 Third, set variables with the Fleet cluster's API Server URL and CA, for the downstream cluster to use for connecting.
 
 ```shell
-API_SERVER_URL=https://...
+API_SERVER_URL=https://<API_URL>:6443
 API_SERVER_CA_DATA=...
 ```
 
+If the API server is not listening on the https port (443), the `API_SERVER_URL` should include the port, e.g. `https://<API_URL>:6443`. The URL can be found in the `.kube/config` file.
 Value in `API_SERVER_CA_DATA` can be obtained from a `.kube/config` file with valid data to connect to the upstream cluster
 (under the `certificate-authority-data` key). Alternatively it can be obtained from within the upstream cluster itself,
 by looking up the default ServiceAccount secret name (typically prefixed with `default-token-`, in the default namespace),
 under the `ca.crt` key.
 
 
-:::caution
-
-__Use proper namespace and release name__:
-For the agent chart the namespace must be `cattle-fleet-system` and the release name `fleet-agent`
-
-:::
-
 :::warning Kubectl Context
 
 __Ensure you are installing to the right cluster__:
@@ -107,6 +101,14 @@ Add Fleet's Helm repo.
 {`helm repo add fleet https://rancher.github.io/fleet-helm-charts/`}
 </CodeBlock>
 
+:::caution
+
+__Use proper namespace and release name__:
+For the agent chart the namespace must be `cattle-fleet-system` and the release name `fleet-agent`
+
+:::
+
+
 Finally, install the agent using Helm.
 <Tabs>
   <TabItem value="helm" label="Install" default>