nptv6: move into dedicated chapter

3 files changed, 67 insertions, 64 deletions

diff --git a/docs/index.rst b/docs/index.rst
index f6b3d595..c0922088 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -39,6 +39,7 @@ VyOS User Guide
    firewall
    routing/index
    nat
+   nptv6
    qos
    high-availability
    vpn/index
diff --git a/docs/nat.rst b/docs/nat.rst
index f4602913..ae0f8ca2 100644
--- a/docs/nat.rst
+++ b/docs/nat.rst
@@ -559,70 +559,6 @@ one external interface:
 Firewall rules are written as normal, using the internal IP address as the
 source of outbound rules and the destination of inbound rules.
 
-NPTv6
------
-
-NPTv6 stands for Network Prefix Translation. It's a form of NAT for IPv6. It's
-described in :rfc:`6296`. NPTv6 is supported in linux kernel since version 3.13.
-
-**Usage**
-
-NPTv6 is very useful for IPv6 multihoming. It is also commonly used when the
-external IPv6 prefix is dynamic, as it prevents the need for renumbering of
-internal hosts when the extern prefix changes.
-
-Let's assume the following network configuration:
-
-* eth0 : LAN
-* eth1 : WAN1, with 2001:db8:e1::/48 routed towards it
-* eth2 : WAN2, with 2001:db8:e2::/48 routed towards it
-
-Regarding LAN hosts addressing, why would you choose 2001:db8:e1::/48 over
-2001:db8:e2::/48? What happens when you get a new provider with a different
-routed IPv6 subnet?
-
-The solution here is to assign to your hosts ULAs_ and to prefix-translate
-their address to the right subnet when going through your router.
-
-* LAN Subnet : fc00:dead:beef::/48
-* WAN 1 Subnet : 2001:db8:e1::/48
-* WAN 2 Subnet : 2001:db8:e2::/48
-
-* eth0 addr : fc00:dead:beef::1/48
-* eth1 addr : 2001:db8:e1::1/48
-* eth2 addr : 2001:db8:e2::1/48
-
-VyOS Support
-^^^^^^^^^^^^
-
-NPTv6 support has been added in VyOS 1.2 (Crux) and is available through
-`nat nptv6` configuration nodes.
-
-.. code-block:: none
-
-  set rule 10 inside-prefix 'fc00:dead:beef::/48'
-  set rule 10 outside-interface 'eth1'
-  set rule 10 outside-prefix '2001:db8:e1::/48'
-  set rule 20 inside-prefix 'fc00:dead:beef::/48'
-  set rule 20 outside-interface 'eth2'
-  set rule 20 outside-prefix '2001:db8:e2::/48'
-
-Resulting in the following ip6tables rules:
-
-.. code-block:: none
-
-  Chain VYOS_DNPT_HOOK (1 references)
-   pkts bytes target   prot opt in   out   source              destination
-      0     0 DNPT     all    eth1   any   anywhere            2001:db8:e1::/48  src-pfx 2001:db8:e1::/48 dst-pfx fc00:dead:beef::/48
-      0     0 DNPT     all    eth2   any   anywhere            2001:db8:e2::/48  src-pfx 2001:db8:e2::/48 dst-pfx fc00:dead:beef::/48
-      0     0 RETURN   all    any    any   anywhere            anywhere
-  Chain VYOS_SNPT_HOOK (1 references)
-   pkts bytes target   prot opt in   out   source              destination
-      0     0 SNPT     all    any    eth1  fc00:dead:beef::/48 anywhere          src-pfx fc00:dead:beef::/48 dst-pfx 2001:db8:e1::/48
-      0     0 SNPT     all    any    eth2  fc00:dead:beef::/48 anywhere          src-pfx fc00:dead:beef::/48 dst-pfx 2001:db8:e2::/48
-      0     0 RETURN   all    any    any   anywhere            anywhere
-
-
 NAT before VPN
 --------------
 
diff --git a/docs/nptv6.rst b/docs/nptv6.rst
new file mode 100644
index 00000000..6fdddb72
--- /dev/null
+++ b/docs/nptv6.rst
@@ -0,0 +1,66 @@
+.. _nptv6:
+
+#####
+NPTv6
+#####
+
+:abbr:`NPTv6 (Network Prefix Translation)` is a form of NAT for IPv6. It's
+described in :rfc:`6296`.
+
+**Usage**
+
+NPTv6 is very useful for IPv6 multihoming. It is also commonly used when the
+external IPv6 prefix is dynamic, as it prevents the need for renumbering of
+internal hosts when the extern prefix changes.
+
+Let's assume the following network configuration:
+
+* eth0 : LAN
+* eth1 : WAN1, with 2001:db8:e1::/48 routed towards it
+* eth2 : WAN2, with 2001:db8:e2::/48 routed towards it
+
+Regarding LAN hosts addressing, why would you choose 2001:db8:e1::/48 over
+2001:db8:e2::/48? What happens when you get a new provider with a different
+routed IPv6 subnet?
+
+The solution here is to assign to your hosts ULAs_ and to prefix-translate
+their address to the right subnet when going through your router.
+
+* LAN Subnet : fc00:dead:beef::/48
+* WAN 1 Subnet : 2001:db8:e1::/48
+* WAN 2 Subnet : 2001:db8:e2::/48
+
+* eth0 addr : fc00:dead:beef::1/48
+* eth1 addr : 2001:db8:e1::1/48
+* eth2 addr : 2001:db8:e2::1/48
+
+VyOS Support
+^^^^^^^^^^^^
+
+NPTv6 support has been added in VyOS 1.2 (Crux) and is available through
+`nat nptv6` configuration nodes.
+
+.. code-block:: none
+
+  set rule 10 inside-prefix 'fc00:dead:beef::/48'
+  set rule 10 outside-interface 'eth1'
+  set rule 10 outside-prefix '2001:db8:e1::/48'
+  set rule 20 inside-prefix 'fc00:dead:beef::/48'
+  set rule 20 outside-interface 'eth2'
+  set rule 20 outside-prefix '2001:db8:e2::/48'
+
+Resulting in the following ip6tables rules:
+
+.. code-block:: none
+
+  Chain VYOS_DNPT_HOOK (1 references)
+   pkts bytes target   prot opt in   out   source              destination
+      0     0 DNPT     all    eth1   any   anywhere            2001:db8:e1::/48  src-pfx 2001:db8:e1::/48 dst-pfx fc00:dead:beef::/48
+      0     0 DNPT     all    eth2   any   anywhere            2001:db8:e2::/48  src-pfx 2001:db8:e2::/48 dst-pfx fc00:dead:beef::/48
+      0     0 RETURN   all    any    any   anywhere            anywhere
+  Chain VYOS_SNPT_HOOK (1 references)
+   pkts bytes target   prot opt in   out   source              destination
+      0     0 SNPT     all    any    eth1  fc00:dead:beef::/48 anywhere          src-pfx fc00:dead:beef::/48 dst-pfx 2001:db8:e1::/48
+      0     0 SNPT     all    any    eth2  fc00:dead:beef::/48 anywhere          src-pfx fc00:dead:beef::/48 dst-pfx 2001:db8:e2::/48
+      0     0 RETURN   all    any    any   anywhere            anywhere
+