Remove username/password from elastic-agent (#1423) (#1433)

* Remove username/password from elastic-agent

* Remove broken references, add es-username/password for k8s

* Update to specify new behaviour

* fix swp file

* add k8s env vars

(cherry picked from commit 44d199c)

Co-authored-by: Michel Laterman <82832767+michel-laterman@users.noreply.github.com>

docs/en/ingest-management/elastic-agent/configuration/env/container-envs.asciidoc

@@ -42,10 +42,6 @@ include::shared-env.asciidoc[tag=elasticsearch-ca]
 
 include::shared-env.asciidoc[tag=kibana-host]
 
-include::shared-env.asciidoc[tag=kibana-username]
-
-include::shared-env.asciidoc[tag=kibana-password]
-
 include::shared-env.asciidoc[tag=kibana-ca]
 
 |===
@@ -93,10 +89,6 @@ include::shared-env.asciidoc[tag=fleet-server-enable]
 
 include::shared-env.asciidoc[tag=fleet-server-elasticsearch-host]
 
-include::shared-env.asciidoc[tag=fleet-server-elasticsearch-username]
-
-include::shared-env.asciidoc[tag=fleet-server-elasticsearch-password]
-
 include::shared-env.asciidoc[tag=fleet-server-elasticsearch-ca]
 
 include::shared-env.asciidoc[tag=fleet-server-service-token]

docs/en/ingest-management/elastic-agent/configuration/env/shared-env.asciidoc

@@ -54,8 +54,8 @@ Overrides `FLEET_HOST` when set.
 [id="env-{type}-kibana-fleet-username"]
 `KIBANA_FLEET_USERNAME`
 
-| (string) The basic authentication username used to connect to {kib} and enable {fleet}.
-Overrides `KIBANA_USERNAME` when set.
+| (string) The basic authentication username used to connect to {kib} and retrieve a `service_token` to enable {fleet}.
+Overrides `ELASTICSEARCH_USERNAME` when set.
 
 *Default:* `elastic`
 
@@ -68,8 +68,8 @@ Overrides `KIBANA_USERNAME` when set.
 [id="env-{type}-kibana-fleet-password"]
 `KIBANA_FLEET_PASSWORD`
 
-| (string) The basic authentication password used to connect to {kib} and enable {fleet}.
-Overrides `KIBANA_PASSWORD` when set.
+| (string) The basic authentication password used to connect to {kib} and retrieve a `service_token` to enable {fleet}.
+Overrides `ELASTICSEARCH_PASSWORD` when set.
 
 *Default:* `changeme`
 
@@ -125,37 +125,6 @@ Overrides `ELASTICSEARCH_HOST` when set.
 
 // =============================================================================
 
-// tag::fleet-server-elasticsearch-username[]
-|
-[id="env-{type}-fleet-server-elasticsearch-username"]
-`FLEET_SERVER_ELASTICSEARCH_USERNAME`
-
-| (string) The basic authentication username used to connect to {es}.
-Overrides `ELASTICSEARCH_USERNAME` when set.
-This user needs the privileges required to publish events to {es}.
-
-// To do: link to required privileges
-
-*Default:* `elastic`
-
-// end::fleet-server-elasticsearch-username[]
-
-// =============================================================================
-
-// tag::fleet-server-elasticsearch-password[]
-|
-[id="env-{type}-fleet-server-elasticsearch-password"]
-`FLEET_SERVER_ELASTICSEARCH_PASSWORD`
-
-| (string) The basic authentication password used to connect to {es}.
-Overrides `ELASTICSEARCH_PASSWORD` when set.
-
-*Default:* `changeme`
-
-// end::fleet-server-elasticsearch-password[]
-
-// =============================================================================
-
 // tag::fleet-server-elasticsearch-ca[]
 |
 [id="env-{type}-fleet-server-elasticsearch-ca"]
@@ -412,8 +381,7 @@ Setting this to `true` is not recommended.
 [id="env-{type}-elasticsearch-username"]
 `ELASTICSEARCH_USERNAME`
 
-| (string) The basic authentication username used to connect to {es}.
-This user needs the privileges required to publish events to {es}.
+| (string) The basic authentication username used to connect to {kib} and retrieve a `service_token` for {fleet}.
 
 // To do: link to required privileges
 
@@ -444,7 +412,7 @@ This user needs the privileges required to publish events to {es}.
 [id="env-{type}-elasticsearch-password"]
 `ELASTICSEARCH_PASSWORD`
 
-| (string) The basic authentication password used to connect to {es}.
+| (string) The basic authentication password used to connect to {kib} and retrieve a `service_token` for {fleet}.
 
 *Default:* `changeme`
 
@@ -497,32 +465,6 @@ contains your CA's certificate.
 
 // =============================================================================
 
-// tag::kibana-username[]
-|
-[id="env-{type}-kibana-username"]
-`KIBANA_USERNAME`
-
-| (string) The basic authentication username used to connect to {kib}.
-
-*Default:* `elastic`
-
-// end::kibana-username[]
-
-// =============================================================================
-
-// tag::kibana-password[]
-|
-[id="env-{type}-kibana-password"]
-`KIBANA_PASSWORD`
-
-| (string) The basic authentication password used to connect to {kib}.
-
-*Default:* `changeme`
-
-// end::kibana-password[]
-
-// =============================================================================
-
 // tag::kibana-ca[]
 |
 [id="env-{type}-kibana-ca"]