Update docs for KAS in Omnibus

Closes https://gitlab.com/gitlab-org/gitlab/-/issues/270133

doc/development/architecture.md

@@ -236,7 +236,7 @@ Table description links:
 | [GitLab Geo Node](#gitlab-geo)                        | Geographically distributed GitLab nodes |       ⚙        |       ⚙      |        ❌         |     ✅      |   ❌    |  ⚙  | EE Only |
 | [GitLab Managed Apps](#gitlab-managed-apps)           | Deploy Helm, Ingress, Cert-Manager, Prometheus, GitLab Runner, JupyterHub, or Knative to a cluster |  ⤓  |  ⤓  |      ⤓       |     ⤓      |   ⤓    |  ⤓  | CE & EE |
 | [GitLab Pages](#gitlab-pages)                         | Hosts static websites                                                |       ⚙        |      ❌       |        ❌         |     ✅      |   ⚙    |  ⚙  | CE & EE |
-| [GitLab Kubernetes Agent](#gitlab-kubernetes-agent)   | Integrate Kubernetes clusters in a cloud-native way                  |       ❌       |      ⚙        |        ❌         |     ❌      |   ⤓    |  ⚙   | EE Only |
+| [GitLab Kubernetes Agent](#gitlab-kubernetes-agent)   | Integrate Kubernetes clusters in a cloud-native way                  |       ⚙        |      ⚙       |        ❌         |     ❌      |   ⤓    |  ⚙   | EE Only |
 | [GitLab self-monitoring: Alertmanager](#alertmanager) | Deduplicates, groups, and routes alerts from Prometheus              |       ⚙        |      ✅       |        ⚙         |     ✅      |   ❌    |  ❌  | CE & EE |
 | [GitLab self-monitoring: Grafana](#grafana)           | Metrics dashboard                                                    |       ✅        |      ⚙       |        ⤓         |     ✅      |   ❌    |  ❌  | CE & EE |
 | [GitLab self-monitoring: Jaeger](#jaeger)             | View traces generated by the GitLab instance                         |       ❌        |      ⚙       |        ❌         |     ❌      |   ⤓    |  ⚙  | CE & EE |
@@ -387,6 +387,7 @@ GitLab Exporter is a process designed in house that allows us to export metrics
 
 - [Project page](https://gitlab.com/gitlab-org/cluster-integration/gitlab-agent)
 - Configuration:
+  - [Omnibus](https://gitlab.com/gitlab-org/omnibus-gitlab/blob/master/files/gitlab-config-template/gitlab.rb.template)
   - [Charts](https://docs.gitlab.com/charts/charts/gitlab/kas/index.html)
 
 [GitLab Kubernetes Agent](../user/clusters/agent/index.md) is an active in-cluster

doc/user/clusters/agent/index.md

@@ -59,7 +59,7 @@ There are several components that work in concert for the Agent to accomplish Gi
 
 The setup process involves a few steps to enable GitOps deployments:
 
-1. Installing the Agent server via GitLab Helm chart.
+1. Installing the Agent server.
 1. Defining a configuration directory.
 1. Creating an Agent record in GitLab.
 1. Generating and copying a Secret token used to connect to the Agent.
@@ -68,13 +68,24 @@ The setup process involves a few steps to enable GitOps deployments:
 
 ### Install the Agent server
 
-The GitLab Kubernetes Agent can only be deployed through our
-[Helm chart](https://gitlab.com/gitlab-org/charts/gitlab). If you don't already
-have GitLab installed via Helm, please refer to our
-[installation documentation](https://docs.gitlab.com/charts/installation/).
+The GitLab Kubernetes Agent can be deployed using [Omnibus
+GitLab](https://docs.gitlab.com/omnibus/) or the [GitLab
+chart](https://gitlab.com/gitlab-org/charts/gitlab). If you don't already have
+GitLab installed, please refer to our [installation
+documentation](https://docs.gitlab.com/ee/install/README.html).
 
 NOTE: **Note:**
-GitLab plans to include the Agent in the [official Linux Package](https://gitlab.com/gitlab-org/gitlab/-/issues/223060) and on [GitLab.com](https://gitlab.com/groups/gitlab-org/-/epics/3834).
+GitLab plans to include the Agent on [GitLab.com](https://gitlab.com/groups/gitlab-org/-/epics/3834).
+
+When using the [Omnibus GitLab](https://docs.gitlab.com/omnibus/) package:
+
+1. Edit `/etc/gitlab/gitlab.rb`:
+
+```plaintext
+gitlab_kas['enable'] = true
+```
+
+1. [Reconfigure GitLab](../../../administration/restart_gitlab.md#omnibus-gitlab-reconfigure).
 
 When installing or upgrading the GitLab Helm chart, consider the following Helm 2 example.
 (If you're using Helm 3, you must modify this example.) You must set `global.kas.enabled=true`