added vpn steps for ubuntu22

source/adminguide/networking/remote_access_vpn.rst

@@ -25,8 +25,8 @@ a network offering that offers the Remote Access VPN service, the
 virtual router (based on the System VM) is used to provide the service.
 CloudStack provides a L2TP-over-IPsec-based remote access VPN service to
 guest virtual networks. Since each network gets its own virtual router,
-VPNs are not shared across the networks. VPN clients native to `Windows,
-Mac OS X <networking/using_remote_access.html>`_ and iOS can be used to connect to the guest networks. The
+VPNs are not shared across the networks. VPN clients native to `Mac OS X <networking/using_remote_access.html#mac-osx>`_,
+`Windows <networking/using_remote_access.html#microsoft-windows-8>`_, `Linux-Ubuntu <networking/using_remote_access.html#ubuntu-22-04-lts>`_ and iOS can be used to connect to the guest networks. The
 account owner can create and manage users for their VPN. CloudStack does
 not use its account database for this purpose but uses a separate table.
 The VPN user database is shared across all the VPNs created by the

source/adminguide/networking/using_remote_access.rst

@@ -146,3 +146,68 @@ Following instruction have been perform using Windows 8.1 using Native VPN clien
    .. image:: /_static/images/vpn/win14.png
       :align: center 
       :width: 400 px
+
+
+Ubuntu 22.04 LTS
+-------
+
+Ubuntu 22.04 LTS does not provide native IPsec VPN client via Network Manager.
+
+#. Install the following packages to enable L2TP over IPsec VPN support:
+
+   ```
+   add-apt-repository universe
+   apt update
+   apt install network-manager-l2tp-gnome network-manager-l2tp strongswan xl2tpd
+   ```
+
+#. Restart Network Manager service to load the new plugins:
+
+   ```
+   systemctl restart NetworkManager
+   ```
+
+#. Navigate to Settings -> Network
+
+   .. image:: /_static/images/vpn/ubuntuvpn1.png
+      :align: center 
+      :width: 400 px
+
+
+#. Click "+" button and add a select Layer 2 Tunneling Protocol (L2TP):
+
+
+   .. image:: /_static/images/vpn/ubuntuvpn2.png
+      :align: center 
+      :width: 400 px
+
+#. Provide the VPN connection information:
+
+.. image:: /_static/images/vpn/ubuntuvpn3.png
+      :align: center
+      :width: 400 px
+
+#. Click on IpSec Settings and configure the following:
+
+   .. image:: /_static/images/vpn/ubuntuvpn4.png
+      :align: center
+      :width: 400 px
+
+#. Click on PPP Settings and select use MPPE encryption:
+
+   .. image:: /_static/images/vpn/ubuntuvpn5.png
+      :align: center
+      :width: 400 px 
+
+#. Connect into VPN
+
+   #. Enable the cloudstack vpn connection.
+   #. verify the connection by checking the ip address assigned on the ppp0 interface
+
+   .. image:: /_static/images/vpn/ubuntuvpn6.png
+      :align: center
+      :width: 400 px 
+
+   .. image:: /_static/images/vpn/ubuntuvpn7.png
+      :align: center
+      :width: 400 px