migrated multiple agent page (#26646)

## Summary & Motivation

Found a link we dont have in the new docs for Dagster Agent. Created
linear
[ticket](https://linear.app/dagster-labs/issue/DOC-649/add-dagster-instance).
## How I Tested These Changes

![image](https://github.com/user-attachments/assets/6a10f53a-c517-4055-8751-3024a5d531d4)

## Changelog

docs/docs-beta/docs/dagster-plus/deployment/deployment-types/hybrid/multiple.md

@@ -2,7 +2,218 @@
 title: Running multiple agents
 sidebar_position: 60
 sidebar_label: Multiple agents
-unlisted: true
 ---
 
-{/* TODO copy from https://docs.dagster.io/dagster-plus/deployment/agents/running-multiple-agents */}
+:::note
+This guide is applicable to Dagster+.
+:::
+
+Each Dagster+ full deployment (e.g., `prod`) needs to have at least one agent running. A single agent is adequate for many use cases, but you may want to run multiple agents to provide redundancy if a single agent goes down.
+
+---
+
+## Running multiple agents in the same environment
+
+To run multiple agents in the same environment (e.g., multiple Kubernetes agents in the same namespace), you can set the number of replicas in the configuration for your particular agent type:
+
+<Tabs groupId="same environment">
+<TabItem value="docker" label="Docker">
+
+### In Docker
+
+In Docker, you can set the number of replicas for a service in the `docker-compose.yaml` file if the deployment mode is set to `replicated` (which is the default):
+
+```yaml
+services:
+  dagster-cloud-agent:
+    ...
+    deploy:
+      mode: replicated
+      replicas: 2
+```
+
+</TabItem>
+<TabItem value="Kubernetes" label="Kubernetes">
+
+### In Kubernetes
+
+In Kubernetes, the number of replicas is set in the Helm chart. You can set the number of replicas in the Helm command:
+
+```shell
+helm upgrade \
+    ...
+    --set replicas=2
+```
+
+or if using a `values.yaml` file:
+
+```yaml
+dagsterCloudAgent:
+  ...
+  replicas: 2
+```
+
+</TabItem>
+<TabItem value="Amazon ECS" label="Amazon ECS">
+
+### In Amazon ECS
+
+In Amazon ECS, the number of replicas can be set via the CloudFormation template:
+
+```yaml
+DagsterCloudAgent:
+  Type: AWS::ECS::Service
+  Properties:
+    ...
+    DesiredCount: 2
+```
+
+If using the CloudFormation template provided by Dagster, the number of replicas can be set via the `NumReplicas` parameter in the Amazon Web Services (AWS) UI.
+
+</TabItem>
+</Tabs>
+
+---
+
+## Running multiple agents in different environments
+
+To run multiple agents in an environment where each agent can not access the others' resources (for example, multiple Kubernetes namespaces or different clusters), enable the `isolated_agents` option. This is supported for all agent types.
+<Tabs groupId="multipleAgentsDifferentEnvironment">
+<TabItem value="Docker" label="Docker">
+
+### In Docker
+
+Add the following to the `dagster.yaml` file:
+
+```yaml
+isolated_agents:
+  enabled: true
+
+dagster_cloud_api:
+  # <your other config>
+  agent_label: "My agent" # optional
+```
+
+</TabItem>
+<TabItem value="Kubernetes" label="Kubernetes">
+
+### In Kubernetes
+
+Add the following options to your Helm command:
+
+```shell
+helm upgrade \
+    ...
+    --set isolatedAgents.enabled=true \
+    --set dagsterCloud.agentLabel="My agent" # optional, only supported on 0.13.14 and later
+```
+
+Or if you're using a `values.yaml` file:
+
+```yaml
+isolatedAgents:
+  enabled: true
+
+dagsterCloud:
+  agentLabel: "My agent" # optional, only supported on 0.13.14 and later
+```
+
+</TabItem>
+<TabItem value="Amazon ECS" label="Amazon ECS">
+
+### In Amazon ECS
+
+The `isolated_agents` option can be set as per-deployment configuration on the `dagster.yaml` file used by your agent. See the [ECS configuration reference](/dagster-plus/deployment/deployment-types/hybrid/amazon-ecs/configuration-reference) guide for more information.
+
+</TabItem>
+</Tabs>
+---
+
+## Routing requests to specific agents
+
+:::note
+Agent queues are a Dagster+ Pro feature.
+:::
+
+Every Dagster+ agent serves requests from one or more queues. By default, requests for each code location are placed on a default queue and your agent will read requests only from that default queue.
+
+In some cases, you might want to route requests for certain code locations to specific agents. For example, routing requests for one code location to an agent running in an on-premise data center, but then routing requests for all other code locations to an agent running in AWS.
+
+To route requests for a code location to a specific agent, annotate the code locations with the name of a custom queue and configure an agent to serve only requests for that queue.
+
+### Step 1: Define an agent queue for the code location
+
+First, set an agent queue for the code location in your [`dagster_cloud.yaml`](/dagster-plus/deployment/code-locations/dagster-cloud-yaml):
+
+```yaml
+# dagster_cloud.yaml
+
+locations:
+  - location_name: data-eng-pipeline
+    code_source:
+      package_name: quickstart_etl
+    executable_path: venvs/path/to/dataengineering_spark_team/bin/python
+    agent_queue: special-queue
+```
+
+### Step 2: Configure an agent to handle the agent queue
+
+Next, configure an agent to handle your agent queue.
+<Tabs groupId="agentQueue">
+<TabItem value="Docker" label="Docker">
+
+#### In Docker
+
+Add the following to your project's [`dagster.yaml`](/todo.md) file:
+{/* [lDagster Instance](https://docs.dagster.io/deployment/dagster-instance) */}
+
+```yaml
+agent_queues:
+  include_default_queue: True # Continue to handle requests for code locations that aren't annotated with a specific queue
+  additional_queues:
+    - special-queue
+```
+
+</TabItem>
+<TabItem value="Kubernetes" name="Kubernetes">
+
+#### In Kubernetes
+
+Add the following options to your Helm command:
+
+```shell
+helm upgrade \
+    ...
+    --set dagsterCloud.agentQueues.additionalQueues={"special-queue"}
+```
+
+Or if you're using a `values.yaml` file:
+
+```yaml
+dagsterCloud:
+  agentQueues:
+    # Continue to handle requests for code locations that aren't
+    # assigned to a specific agent queue
+    includeDefaultQueue: true
+    additionalQueues:
+      - special-queue
+```
+
+</TabItem>
+<TabItem value="Amazon ECS" label="Amazon ECS">
+
+#### In Amazon ECS
+
+Modify your ECS Cloud Formation template to add the following configuration to the `config.yaml` passed to the agent:
+
+```yaml
+agent_queues:
+  # Continue to handle requests for code locations that aren't
+  # assigned to a specific agent queue
+  include_default_queue: true
+  additional_queues:
+    - special-queue
+```
+
+</TabItem>
+</Tabs>