Document RHEL 9 to RHEL 10.1 upgrade process

Added upgrade path information from RHEL 9 to RHEL 10.1 and updated prerequisites for the upgrade process.

Author: Mauricio

support/azure/virtual-machines/linux/leapp-upgrade-process-rhel-7-and-8.md

@@ -25,6 +25,8 @@ For more information about performing a Leapp upgrade on custom, golden, or PAYG
 
 - [Upgrading from RHEL 8 to RHEL 9](https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/9/html/upgrading_from_rhel_8_to_rhel_9/index)
 
+- [Upgrading from RHEL 9 to RHEL 10](https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/10/html/upgrading_from_rhel_9_to_rhel_10/index)
+
 ## Prerequisites
 
 - Make a backup of the Linux VM or a snapshot of the OS disk.
@@ -141,6 +143,56 @@ You can perform an in-place upgrade from RHEL 8 to the following RHEL 9 minor ve
 
 8. RHEL 9 no longer supports the legacy network-scripts package, which was deprecated in RHEL 8. Before upgrading, migrate your custom network scripts and create a NetworkManager dispatcher script to run your existing custom scripts. For more information, see [Migrating custom network scripts to NetworkManager dispatcher scripts](https://access.redhat.com/solutions/6900331).
 
+### [RHEL 9.7 to RHEL 10.1](#tab/rhel9-rhel10)
+
+You can perform an in-place upgrade from RHEL 9 to the following RHEL 10 minor versions.
+
+| Source OS version| Target version     |
+|------------------|--------------------|
+| RHEL 9.7         | RHEL 10.1          |     
+
+> [!NOTE]  
+> For more information, see [Supported in-place upgrade paths for Red Hat Enterprise Linux](https://access.redhat.com/articles/4263361).
+
+
+> [!NOTE]  
+>  If you locked the VM to a minor release, remove the version lock. For more information, see [Switch a RHEL 9.x VM back to non-EUS](/azure/virtual-machines/workloads/redhat/redhat-rhui#switch-a-rhel-server-to-non-eus-repositories).
+
+
+
+1. If you restricted packages to a specific version using the `dnf-command(versionlock)` command, remove the restriction:
+
+    ```bash
+    sudo dnf versionlock clear
+    ```
+
+2. To ensure your system is ready for the upgrade, enable required RHUI repositories and install required RHUI packages:
+
+    ```bash
+    sudo dnf config-manager --set-enabled rhui-microsoft-azure-rhel9
+    sudo dnf -y install rhui-azure-rhel9 leapp-rhui-azure
+    ```
+3. Install the Leapp utility:
+
+    ```bash
+    sudo dnf install leapp-upgrade
+    ```
+4. Update all packages to the latest RHEL 8 version:
+
+    ```bash
+    sudo dnf update
+    ```
+5. Reboot the VM:
+
+    ```bash
+    sudo reboot
+    ```
+6. To prevent upgrade failures, temporarily disable your antivirus software.
+
+7. Before running the `leapp preupgrade` command, disable any configuration management systems with a client-server architecture (such as Puppet, Salt, or Chef) or an agentless architecture (such as Ansible).
+
+8. If the system has been previously upgraded from RHEL 8 to RHEL 9, ensure that all required post-upgrade steps have been completed. For more information, see Performing post-upgrade tasks in the Upgrading from RHEL 8 to RHEL 9 guide[Performing post-upgrade](https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/9/html-single/upgrading_from_rhel_8_to_rhel_9/index#performing-post-upgrade-tasks-on-the-rhel-9-system_upgrading-from-rhel-8-to-rhel-9)
+
 ---
 
 ## Leapp pre-upgrade process
@@ -168,6 +220,20 @@ sudo leapp preupgrade --target <target_os_version> --no-rhsm
 
 Replace `<target_os_version>` with the target OS version, for example, `9.4` or `9.5`. 
 
+### [RHEL 9.7to RHEL 10.1](#tab/rhel9-rhel10)
+
+> [!NOTE]  
+> If you use the sudo command, you must use the `-r unconfined_r -t unconfined_t` options when entering each leapp command.
+
+Run the following `leapp preupgrade` command:
+
+```bash
+sudo leapp preupgrade --target <target_os_version> --no-rhsm
+```
+
+Replace `<target_os_version>` with the target OS version, for example, `10.1`. 
+
+
 ---
 
 Check the report located in the `/var/log/leapp/leapp-report.txt` file and resolve any identified issues manually. Some problems come with recommended fixes. Inhibitor issues must be resolved before you can proceed with the upgrade. For detailed information about the various issues that might appear in the report, see [Troubleshooting Red Hat OS upgrade issues](troubleshoot-red-hat-os-upgrade-issues.md).
@@ -229,6 +295,33 @@ Continue the Leapp upgrade process after the Leapp pre-upgrade report shows no e
     sudo reboot
     ```
 
+### [RHEL 9.7to RHEL 10.1](#tab/rhel9-rhel10)
+
+
+1. Run the following `leapp upgrade` command:
+
+    ```bash
+    sudo leapp upgrade --target <target_os_version> --no-rhsm
+    ```
+    
+    > [!NOTE]
+    > - Replace `<target_os_version>` with the target OS version, for example, `10.1`.
+    > - If you want to perform an automatic reboot, which is needed during the upgrade process, add the `--reboot` option to the `leapp upgrade` command.
+
+2. If the `--reboot` option wasn't included in the previous command, monitor the Serial Console. Once the upgrade process shows that a reboot is required to continue the process as follows, manually reboot the VM:
+
+
+    ```output
+    ====> * add_upgrade_boot_entry
+            Add new boot entry for Leapp provided initramfs.
+    A reboot is required to continue. Please reboot your system.
+    ```
+    
+    ```bash
+    sudo reboot
+    ```
+
+
 ---
 
 Once the upgrade is finished, check if the system is in the desired state.
@@ -401,8 +494,49 @@ Once the VM is successfully upgraded, perform the following tasks:
         > [!IMPORTANT]  
         > Removing this data might limit Microsoft and Red Hat Support's ability to investigate and troubleshoot post-upgrade problems.
 
+
+### [RHEL 9.7to RHEL 10.1](#tab/rhel9-rhel10)
+
+
+1. Delete all remaining Leapp packages, including the *`snactor`* package, from the exclude list in the */etc/dnf/dnf.conf* configuration file. These Leapp packages are installed during the in-place upgrade.
+
+    ```bash
+    sudo dnf config-manager --save --setopt exclude=''
+    ```
+
+2. Remove all remaining RHEL 8 packages, including any remaining Leapp packages.
+
+   1. Locate remaining RHEL 8 packages.
+
+       ```bash
+       sudo rpm -qa | grep -e '\.el[789]' | grep -vE '^(gpg-pubkey|libmodulemd|katello-ca-consumer)' | sort
+       ```
+
+   2. Remove remaining RHEL 8 packages from your RHEL 9 VM:
+
+       ```bash
+       sudo dnf remove $(rpm -qa | grep \.el[789] | grep -vE 'gpg-pubkey|libmodulemd|katello-ca-consumer')
+       ```
+
+   3. Remove remaining Leapp dependency packages:
+
+       ```bash
+       sudo dnf remove leapp-deps-el10 leapp-repository-deps-el10
+       ```
+
+   4. (Optional) Remove all remaining upgrade-related data from the system:
+
+       ```bash
+       sudo rm -rf /var/log/leapp /root/tmp_leapp_py3 /var/lib/leapp
+       ```
+
+        > [!IMPORTANT]  
+        > Removing this data might limit Microsoft and Red Hat Support's ability to investigate and troubleshoot post-upgrade problems.
+
+
 ---
 
 [!INCLUDE [Third-party disclaimer](../../../includes/third-party-disclaimer.md)]
 
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+