Merge pull request #303091 from sushantjrao/break-glass-setup

Update howto-replace-network-devices.md

Author: denrea

articles/operator-nexus/howto-replace-network-devices.md

@@ -9,9 +9,12 @@ ms.date: 08/12/2024
 ms.custom: template-how-to, devx-track-azurecli
 ---
 
-# Replace a device in Azure Operator Nexus Network Fabric (NNF)
+# Replace a network device in Azure Operator Nexus Network Fabric (NNF)
 
-This article describes how to replace a faulty or underperforming device in Azure Operator Nexus Network Fabric (NNF) using the RMA (Return Material Authorization) process which ensures minimal disruption and safe reintegration of the replacement hardware into the fabric.
+This article explains how to replace a faulty or underperforming network device in Azure Operator Nexus Network Fabric (NNF).
+It covers devices such as the Top of Rack (TOR) switch, Customer Edge (CE) switch, Network Packet Broker (NPB), and the Management Switch.
+The replacement is performed using the Return Material Authorization (RMA) process.
+This process is designed to minimize service disruption and safely reintegrate the new hardware into the fabric.
 
 ## Scenarios for device replacement
 
@@ -25,15 +28,20 @@ Device replacement may be required in the following situations:
 
 ## Prerequisites
 
-- Azure CLI installed and configured.
+To ensure a smooth and timely RMA process, verify the following prerequisites before initiating deployment:
 
-- Required permissions to manage Microsoft.ManagedNetworkFabric resources.
+  - Azure CLI is installed and properly configured
 
-- Replacement device powered on and connected physically.
+  - Permissions are granted to manage Microsoft.ManagedNetworkFabric resources
 
-- Replacement device must support Zero Touch Provisioning (ZTP).
+  - Replacement device is powered on and physically connected
 
-- To ensure a smooth and timely RMA process, please verify the following before initiating deployment:
+  - Replacement device supports Zero Touch Provisioning (ZTP)
+
+  - To prevent failure during the device disable action if the device is affected by continuous reboots due to hardware issues, it is advised to power off the device prior to initiating the RMA process. 
+
+  - Before initiating the RMA deployment, perform the following checks:
+    
 
     - Interface Speed Validation
 
@@ -42,14 +50,20 @@ Device replacement may be required in the following situations:
         - If the speed is below 100 Mbps, update it accordingly to prevent delays or potential timeouts during the RMA process.
 
     - Device Storage Check
-        - Ensure the device has a minimum of 2 GB of free space available.
+        - Ensure the device has a minimum of 3 GB of free space available.
 
-        - This is required to successfully download and stage the necessary image files.
+        - This action is required to successfully download and stage the necessary image files.
 
+## Device types supported
+
+- Customer Edge (CE)
+- Top of Rack (TOR)
+- Management Switch (Mgmt Switch)
+- Network Packet Broker (NPB)
 
 ## Steps to replace a device
 
-1. Disable administrative state.
+### Step 1: Disable administrative state
 
 Use the following command to disable the administrative state of the device:
 
@@ -60,19 +74,25 @@ az networkfabric device update-admin-state \
   --resource-group "resource-group-name"
 ```
 
-This action:
+This action sets the following states:
 
-- Moves the device to a degraded state: EnabledDegraded.
+- Device Administrative State: Disabled
 
-- Excludes the device from all control plane actions such as:
+- Fabric Administrative State: EnabledDegraded
 
-    - Certificate rotations
-    
-    - Password rotations
-    
-    - Fabric upgrades
+>[!Note] 
+> This action is not permitted by the service, if any of the following operations are in progress at the fabric level:
+> - Device upgrade
+> - Configuration push
+> - Secret or certificate updates
+> - Administrative lock
+> - Terminal Server (TS) reprovisioning.
+
+### Step 2: Update the serial number
 
-2. Update the serial number.
+Execution conditions:
+- Device Administrative State must be `Disabled`
+- Fabric Administrative State must be `EnabledDegraded`
 
 Once the replacement device is physically installed, update its serial number in the fabric resource:
 
@@ -83,14 +103,26 @@ az networkfabric device update \
   --resource-group "resource-group-name"
 ```
 
-3. Ensure device is in ZTP Mode.
+Error recovery guidance:
+
+- If RMA fails due to an incorrect serial number, repatching is allowed without a support ticket.
+
+- If validation fails after device bootstrap, the system returns the status: Device Unable to Boot Up - Failed.
+
+This action performs the following tasks:
+
+- Update serial number stored in Azure ARM resource
+
+- Keeps the device in `Disabled` state and Fabric Administrative State in `EnabledDegraded`
+
+### Step 3: Ensure device is in ZTP Mode
 
 Verify that the replacement device is in ZTP mode. If not, configure the device for ZTP before continuing.
 
 > [!Note]
 > ZTP enables automatic configuration retrieval during the RMA process.
 
-4. Set RMA State.
+### Step 4: Initiate RMA process
 
 Initiate the RMA process using the following command:
 
@@ -101,23 +133,33 @@ az networkfabric device update-admin-state \
   --resource-group "resource-group-name"
 ```
 
-This will:
+- Network Fabric Controller pushes all required configuration files to the new replaced device. It is advised to retry the operation if there's transient failures until success is confirmed.
+
+- The device boots into its base configuration using the maintenance profile. This condition applies only to TOR and CE device types.
+
+This action sets the following states:
 
-- Trigger the Network Fabric Controller to push all required configuration files to the replacement device.
+- Device Administrative State: UnderMaintenance
 
-- Retry the operation if there is transient failures until success is confirmed.
+- Fabric Administrative State: EnabledDegraded
 
-5. Refresh configuration
+### Step 5: Refresh configuration
 
 This step pushes the latest configuration to the device after it enters maintenance mode (applicable only for CE and TOR).
 
 ```Azure CLI
 az networkfabric device refresh-configuration --resource-name <resource-name> --resource-group <rg-name>
 ```
 
-This will push the latest config to the device.
+This action pushes the latest configuration to the device. 
 
-6. Enable administrative state.
+This action keeps the device in following states:
+
+- Device Administrative State: UnderMaintenance
+
+- Fabric Administrative State: EnabledDegraded
+
+### Step 6: Enable administrative state.
 
 Once configuration is applied successfully, bring the device back into active service:
 
@@ -128,9 +170,14 @@ az networkfabric device update-admin-state \
   --resource-group "resource-group-name"
 ```
 
-This will: 
+This action sets the following state once it's fully healthy and synchronized with the fabric:
+
+- Device Administrative State: `Enabled`
+
+- Fabric Administrative State: `Enabled` 
 
-- Sets device state to Enabled once it's fully healthy and synchronized with the fabric.
+>[!Note]
+> In a given fabric if there are any other device is in Disabled state then the Fabric Administrative State will maintained as : `EnabledDegraded` 
 
 ## Summary