====== Accel-ppp Support in RADIUSdesk ======
===== Introduction =====
  * As of November 2023, RADIUSdesk can centrally manage Accel-ppp on Ubuntu and Raspberry Pi based devices.
  * This is done by a lightweight agent that interacts with RADIUSdesk.
  * Each device now has the ability to be configured though a web applet on RADIUSdesk.
  * The agent also reports back to RADIUSdesk on the status of the service and any active sessions.
  * The following graphic shows how everything fits together.
{{:technical:pppoe:acell-radiusdesk.jpg|}}

===== Accel-ppp Servers Applet =====
  * The Accel-ppp Server applet can be found under the **Other** grouping.
  * It has three sub tabs
        * The **Servers** tab displays all of the Accel-ppp servers which are managed centrally.
        * The **Profiles** tab is used to define various profiles which are associated with one of more servers.
        * The **New Arrivals** lists Accel-ppp servers which reported to RADIUSdesk but which require on-boarding.
==== Profiles ====
  * We will cover Profiles first although it is the second sub-tab since it is required to have a profile ready in order to define a server.
  * Profiles are used to manage the major part of the settings which will be applied to a server.
  * Settings are dynamically formulated in the reply when the RADISUdesk Accel-ppp agent contacts RADIUSdesk.
  * The settings for each Accel-ppp server can be divided into three categories.
        * **Common** settings which hardly differ between servers. (This is the bulk of them)
        * **Unique** settings which you might want to tweak should the need arise.
        * **Specific** settings which are required to differentiate one Accel-ppp server from another.
=== Common Settings (Base Configs) ===
  * Common settings are stored inside a CakePHP config file. (///var/www/rdcore/cake4/rd_cake/config/AccelPresets.php//)

  * One can define various sets of these common settings, giving each a **unique name**.
<code php>
<?php
//Default settings for accel-ppp

$config['AccelPresets']['Default'] = [

    'modules'   => [
        'log_file',
        'pppoe',
        'auth_pap',
        'radius',
        'ippool',
        'shaper',   
    ],  
    'core'      => [
        'log-error' => '/var/log/accel-ppp/core.log',
        'thread-count'  => 4,
    ],
</code>
  * We refer to them as **Base Configs**.
  * There is one already called **Default**.
  * The keys of these configs maps to sections of the **/etc/accel-ppp.conf** file.
  * Should you wish to add or modify these configs; it can be done by editing /var/www/rdcore/cake4/rd_cake/config/AccelPresets.php.
  * The various configs will then appear as a select-able Base Config list when managing profiles.
  * When one select a Base Config from the list; the values in the GUI are populated from the selected Base Config.
  * You can then edit those populated values so they are **unique** to the profile you are managing.
  * See screenshot below.
{{:technical:pppoe:acell-profiles.png|}}

=== Unique Settings (Profiles) ===
  * Profiles allow you to override certain values which were specified in the Base Config so that they become unique to that profile.
  * These include items which might need tweaking for certain environments.
  * Each of the sections inside the GUI maps to a section in the **/etc/accel-ppp.conf** file.

=== Specific Settings (Server) ===
  * This is the final category and one that is specific to an Accel-ppp server in the applet.
  * An Accel-ppp server needs a mandatory Profile (Unique settings) and then two items which are specific.
        * **Interface** This is the interface name on the server where we want to run the PPPoE servie on.
        * **NAS Identifier** This is the specific identifier used to identify the Accel-ppp server on RADIUS.
{{:technical:acell-specific.png|}}



==== Servers ====
  * Although the Servers tab is first we started with the Profiles tab since we need to have a Profile available which we can associate with a server.
  * Each server has the following mandatory fields.
        * **Name** A unique name to identify the server with.
        * **MAC Address** This has to match the MAC Address of the interface on the device running Accel-ppp and is used as a identity field.
        * **Server Profile** This was covered earlier in this document.
        * **Interface** The name of the interface on which you plan to run the PPPoE service on (using Accel-ppp)
        * **NAS Identifier** Used to identify the server when interacting with the RADIUS server.

=== Servers GUI ===
{{:technical:pppoe:acell-server.png|}}
  * The screenshot above is from the Accel-ppp server applet. 
  * Let's look at some key points
        * The Refresh button has an option to automatically refresh at fixed intervals. This is handy if you want to see when an Accel-ppp server comes online without having to hit the refresh button the whole time.
        * Next to it is a toggle button which allows you to see either all defined server or only those servers which are currently online.
        * The Add, Delete and Edit buttons should be self explanatory.
        * The **Restart Service** button is used to set the restart service flag on a selected server. 
        * If it is set (indicated visually with a gears icon prepended to the name) and the next heartbeat arrives from the RADIUSdesk Accel-ppp agent. the agent will detect the flag and restart the Accel-ppp service.
        * The visual indication will also be cleared.
        * The final button is used to launch a new tab which will list all the active sessions.

{{:technical:pppoe:acell-sessions.png|}}
  * The final button on the active sessions tab in turn will allow you to terminate selected sessions.
  * It works is a similar way to the **Restart Service** button for the server itself where a flag is set and there is a visual indication that a session is marked for disconnect until the next heartbeat where it will be cleared and the RADIUSdesk Accel-ppp agent will terminate the user's session.

==== New Arrivals ====
{{:technical:pppoe:acell-arrival.png|}}
  * Any of the Accel-ppp servers that still needs on-boarding will be listed under **New Arrivals**.
  * Simply select the one you want to on-board and provide the required information to allow it to become part of the managed servers.
  * Reboot the device after on-boarding and the configuration will be applied through the RADIUSdesk Accel-ppp agent.

==== Next Steps ====
  * Be sure to check out the steps to follow on the Ubuntu or Raspberry Pi to install the RADIUSdesk Accel-ppp agent so it can be managed by RADIUSdesk.