Change the wording on the Licenser.Enforce when the endpoint is not r…

…eachable. (elastic#13771)

* Change the wording on the Licenser.Enforce when the endpoint is not
reachable.

The original wrapped errors did not make it clear what was our intend to
call the _xpack api.

CHANGELOG.next.asciidoc

@@ -103,8 +103,8 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d
 - Fix mapping for kubernetes.labels and kubernetes.annotations in add_kubernetes_metadata. {issue}12638[12638] {pull}13226[13226]
 - Fix case insensitive regular expressions not working correctly. {pull}13250[13250]
 - Disable `add_kubernetes_metadata` if no matchers found. {pull}13709[13709]
+- Better wording for xpack beats when the _xpack endpoint is not reachable. {pull}13771[13771]
 - Recover from panics in the javascript process and log details about the failure to aid in future debugging. {pull}13690[13690]
-
 *Auditbeat*
 
 - Process dataset: Fixed a memory leak under Windows. {pull}12100[12100]

x-pack/libbeat/licenser/es_callback.go

@@ -6,6 +6,7 @@ package licenser
 
 import (
 	"fmt"
+	"strings"
 
 	"github.com/pkg/errors"
 
@@ -16,12 +17,16 @@ import (
 // Enforce setups the corresponding callbacks in libbeat to verify the license on the
 // remote elasticsearch cluster.
 func Enforce(log *logp.Logger, name string, checks ...CheckFunc) {
+	name = strings.Title(name)
+
 	cb := func(client *elasticsearch.Client) error {
 		fetcher := NewElasticFetcher(client)
 		license, err := fetcher.Fetch()
 
 		if err != nil {
-			return errors.Wrapf(err, "cannot retrieve the elasticsearch license")
+			return errors.Wrapf(err, "cannot retrieve the elasticsearch license from the /_xpack endpoint, "+
+				"%s requires the default distribution of Elasticsearch. Please make the endpoint accessible "+
+				"to %s so it can verify the license.", name, name)
 		}
 
 		if license == OSSLicense {