Note: Doc team updates the current version of the documentation and the
two previous versions (n-2), but we address *only high-priority, or
customer-reported issues* for -2 releases in support.
Describe the changes in the doc and link to your dev story:

1. - [x] Mandatory: Add the required version to the Fix version/s field.

2. - [x] Mandatory: Choose the type of documentation change or review.

• [ ] We need to update to an existing topic

• [ ] We need to add a new document to an existing section

• [x] We need a whole new section; this is a function not
  documented before and doesn't belong in any current section

• [ ] We need an Operator Advisory review and approval

• [ ] We need a z-Stream (Errata) Advisory and Release note
  for MCE and/or ACM

3. - [ ] *Mandatory: *Use the following link to open the doc and find where the
documentation update should go. Note: As the feature and doc is
understood and developed, this placement decision may change:

• Published doc: https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_management_for_kubernetes/2.10
• Source: https://github.com/stolostron/rhacm-docs

Add a new section called Installing Multicluster Global Hub in an existing ACM Hub Cluster

in https://github.com/stolostron/rhacm-docs/blob/2.13_stage/global_hub/global_hub_overview.adoc

the content can be:

Follow the following instruction to install Global hub operator.

• Installing Multicluster Global Hub in a connected environment

• Installing Multicluster Global Hub in a disconnected environment

When you create the MulticlusterGlobalHub CR, you need to set `installAgentOnLocal` as true. Once completed the deployment, you can see the global hub agent is installed in multicluster-global-hub-agent namespace.

Here is the explanation for `installAgentOnLocal` field:

InstallAgentOnLocal determines whether deploy the Global Hub Agent on the local hub cluster or not.
If set to true, the Global Hub Agent will be installed on the local hub cluster only.
If set to false, the Global Hub Agent will not be installed on the local hub cluster.
Currently, switching the value of this field is not supported after the Global Hub is installed.

When you access the global hub grafana, you can see all the managed clusters and policies are shown in dashboards and the hub cluster name is local-cluster.

4. - [ ] Mandatory for GA content:

• [ ] Add steps, the diff, known issue, and/or other important
  conceptual information in the following space:

• [ ] *Add Required access level *(example, *Cluster
  Administrator*) for the user to complete the task:

• [ ] Add verification at the end of the task, how does the user
  verify success (a command to run or a result to see?)

• [ ] Add link to dev story here:

5. - [ ] Mandatory for bugs: What is the diff? Clearly define what the
problem is, what the change is, and link to the current documentation. Only
use this for a documentation bug.