Rewritten the L2TP documentation

Rewritten the L2TP documentation
Added the example 'PPPoE over L2TP' to blueprints

2 files changed, 170 insertions, 0 deletions

diff --git a/docs/configexamples/index.rst b/docs/configexamples/index.rst
index 7134e14c..d5973eb2 100644
--- a/docs/configexamples/index.rst
+++ b/docs/configexamples/index.rst
@@ -17,6 +17,7 @@ This chapter contains various configuration examples:
    wan-load-balancing
    pppoe-ipv6-basic
    l3vpn-hub-and-spoke
+   lac-lns
    inter-vrf-routing-vrf-lite
    qos
    segment-routing-isis
diff --git a/docs/configexamples/lac-lns.rst b/docs/configexamples/lac-lns.rst
new file mode 100644
index 00000000..b246c4d3
--- /dev/null
+++ b/docs/configexamples/lac-lns.rst
@@ -0,0 +1,169 @@
+:lastproofread: 2024-02-21
+
+.. _examples-lac-lns:
+
+###############
+PPPoE over L2TP
+###############
+
+This document is to describe a basic setup using PPPoE over L2TP.
+LAC and LNS are components of the broadband topology.
+LAC - L2TP access concentrator
+LNS -  L2TP Network Server
+LAC and LNS forms L2TP tunnel. LAC receives packets from PPPoE clients and
+forward them to LNS. LNS is the termination point that comes from PPP packets
+from the remote client.
+
+In this example we use VyOS 1.5 as LNS and Cisco IOS as LAC.
+All users with domain **vyos.io** will be tunneled to LNS via L2TP.
+
+Network Topology
+================
+
+.. image:: /_static/images/lac-lns-diagram.jpg
+   :width: 60%
+   :align: center
+   :alt: Network Topology Diagram
+
+Configurations
+==============
+
+LAC
+---
+
+.. code-block:: none
+
+    aaa new-model
+    !
+    aaa authentication ppp default local
+    !
+    vpdn enable
+    vpdn aaa attribute nas-ip-address vpdn-nas
+    !
+    vpdn-group LAC
+     request-dialin
+      protocol l2tp
+      domain vyos.io
+     initiate-to ip 192.168.139.100
+     source-ip 192.168.139.101
+     local name LAC
+     l2tp tunnel password 0 test123
+    !
+    bba-group pppoe MAIN-BBA
+     virtual-template 1
+    !
+    interface GigabitEthernet0/0
+     description To LNS
+     ip address 192.168.139.101 255.255.255.0
+     duplex auto
+     speed auto
+     media-type rj45
+    !
+    interface GigabitEthernet0/1
+     description To PPPoE clients
+     no ip address
+     duplex auto
+     speed auto
+     media-type rj45
+     pppoe enable group MAIN-BBA
+    !
+
+LNS
+---
+
+.. code-block:: none
+
+    set interfaces ethernet eth0 address '192.168.139.100/24'
+    set nat source rule 100 outbound-interface name 'eth0'
+    set nat source rule 100 source address '10.0.0.0/24'
+    set nat source rule 100 translation address 'masquerade'
+    set protocols static route 0.0.0.0/0 next-hop 192.168.139.2
+    set vpn l2tp remote-access authentication mode 'radius'
+    set vpn l2tp remote-access authentication radius server 192.168.139.110 key 'radiustest'
+    set vpn l2tp remote-access client-ip-pool TEST-POOL range '10.0.0.2-10.0.0.100'
+    set vpn l2tp remote-access default-pool 'TEST-POOL'
+    set vpn l2tp remote-access gateway-address '10.0.0.1'
+    set vpn l2tp remote-access lns host-name 'LAC'
+    set vpn l2tp remote-access lns shared-secret 'test123'
+    set vpn l2tp remote-access name-server '8.8.8.8'
+    set vpn l2tp remote-access ppp-options disable-ccp
+
+.. note:: This setup requires the Compression Control Protocol (CCP)
+          being disabled, the command ``set vpn l2tp remote-access ppp-options disable-ccp``
+          accomplishes that.
+
+Client
+------
+
+In this lab we use Windows PPPoE client.
+
+.. image:: /_static/images/lac-lns-winclient.jpg
+   :width: 100%
+   :align: center
+   :alt: Window PPPoE Client Configuration
+
+Monitoring
+----------
+
+Monitoring on LNS side
+
+.. code-block:: none
+
+    vyos@vyos:~$ show l2tp-server sessions
+     ifname |   username   |    ip    | ip6 | ip6-dp |   calling-sid   | rate-limit | state  |  uptime  | rx-bytes  | tx-bytes
+    --------+--------------+----------+-----+--------+-----------------+------------+--------+----------+-----------+----------
+     l2tp0  | test@vyos.io | 10.0.0.2 |     |        | 192.168.139.101 |            | active | 00:00:35 | 188.4 KiB | 9.3 MiB
+
+Monitoring on LAC side
+
+.. code-block:: none
+
+    Router#show pppoe session
+         1 session  in FORWARDED (FWDED) State
+         1 session  total
+    Uniq ID  PPPoE  RemMAC          Port                    VT  VA         State
+               SID  LocMAC                                      VA-st      Type
+          1      1  000c.290b.20a6  Gi0/1                    1  N/A        FWDED
+                    0c58.88ac.0001
+
+    Router#show l2tp
+    L2TP Tunnel and Session Information Total tunnels 1 sessions 1
+
+    LocTunID   RemTunID   Remote Name   State  Remote Address  Sessn L2TP Class/
+                                                               Count VPDN Group
+    23238      2640       LAC           est    192.168.139.100 1     LAC
+
+    LocID      RemID      TunID      Username, Intf/      State  Last Chg Uniq ID
+                                     Vcid, Circuit
+    25641      25822      23238      test@vyos.io, Gi0/1  est    00:05:36 1
+
+Monitoring on RADIUS Server side
+
+.. code-block:: none
+
+    root@Radius:~# cat /var/log/freeradius/radacct/192.168.139.100/detail-20240221
+    Wed Feb 21 13:37:17 2024
+            User-Name = "test@vyos.io"
+            NAS-Port = 0
+            NAS-Port-Id = "l2tp0"
+            NAS-Port-Type = Virtual
+            Service-Type = Framed-User
+            Framed-Protocol = PPP
+            Calling-Station-Id = "192.168.139.101"
+            Called-Station-Id = "192.168.139.100"
+            Acct-Status-Type = Start
+            Acct-Authentic = RADIUS
+            Acct-Session-Id = "45c731e169d9a4f1"
+            Acct-Session-Time = 0
+            Acct-Input-Octets = 0
+            Acct-Output-Octets = 0
+            Acct-Input-Packets = 0
+            Acct-Output-Packets = 0
+            Acct-Input-Gigawords = 0
+            Acct-Output-Gigawords = 0
+            Framed-IP-Address = 10.0.0.2
+            NAS-IP-Address = 192.168.139.100
+            Event-Timestamp = "Feb 21 2024 13:37:17 UTC"
+            Tmp-String-9 = "ai:"
+            Acct-Unique-Session-Id = "ea6a1089816f19c0d0f1819bc61c3318"
+            Timestamp = 1708522637