sdn: rework introduction and installation and add support status

Provide installation documentation for opt-in features, document the
current support status, and rework the overview and introduction of
the whole chapter.

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

diff --git a/pvesdn.adoc b/pvesdn.adoc
index 43e93399d3fd96146296a685bceebec514a3b26f..719533c91b32e8df75d1d165da4a701f125a3dd7 100644 (file)
--- a/pvesdn.adoc
+++ b/pvesdn.adoc
@@ -5,64 +5,125 @@ ifndef::manvolnum[]
 :pve-toplevel:
 endif::manvolnum[]
 
-The **S**oftware-**D**efined **N**etwork (SDN) feature allows you to create
-virtual networks (VNets) at the datacenter level.
+The **S**oftware-**D**efined **N**etwork (SDN) feature in {pve} enables the
+creation of virtual zones and networks (VNets). This functionality simplifies
+advanced networking configurations and multitenancy setup."
 
-WARNING: SDN is currently an **experimental feature** in {pve}. This
-documentation for it is also still under development. Ask on our
-xref:getting_help[mailing lists or in the forum] for questions and feedback.
+[[pvesdn_overview]]
+Introduction
+------------
+
+The {pve} SDN allows for separation and fine-grained control of virtual guest
+networks, using flexible, software-controlled configurations.
+
+Separation is managed through *zones*, virtual networks (*VNets*), and
+*subnets*.  A zone is its own virtually separated network area.  A VNet is a
+virtual network that belongs to a zone. A subnet is an IP range inside a VNet.
+
+Depending on the type of the zone, the network behaves differently and offers
+specific features, advantages, and limitations.
 
+Use cases for SDN range from an isolated private network on each individual node
+to complex overlay networks across multiple PVE clusters on different locations.
+
+After configuring an VNet in the cluster-wide datacenter SDN administration
+interface, it is available as a common Linux bridge, locally on each node, to be
+assigned to VMs and Containers.
+
+
+[[pvesdn_support_status]]
+Support Status
+--------------
+
+History
+~~~~~~~
+
+The {pve} SDN stack has been available as an experimental feature since 2019 and
+has been continuously improved and tested by many developers and users.
+With its integration into the web interface in {pve} 6.2, a significant
+milestone towards broader integration was achieved.
+During the {pve} 7 release cycle, numerous improvements and features were added.
+Based on user feedback, it became apparent that the fundamental design choices
+and their implementation were quite sound and stable. Consequently, labeling it
+as `experimental' did not do justice to the state of the SDN stack.
+For {pve} 8, a decision was made to lay the groundwork for full integration of
+the SDN feature by elevating the management of networks and interfaces to a core
+component in the {pve} access control stack.
+In {pve} 8.1, two major milestones were achieved: firstly, DHCP integration was
+added to the IP address management (IPAM) feature, and secondly, the SDN
+integration is now installed by default.
+
+Current Status
+~~~~~~~~~~~~~~
+
+The current support status for the various layers of our SDN installation is as
+follows:
+
+- Core SDN, which includes VNet management and its integration with the {pve}
+  stack, is fully supported.
+- IPAM, including DHCP management for virtual guests, is in tech preview.
+- Complex routing via FRRouting and controller integration are in tech preview.
 
 [[pvesdn_installation]]
 Installation
 ------------
 
-To enable the experimental Software-Defined Network (SDN) integration, you need
-to install the `libpve-network-perl` package on every node:
+SDN Core
+~~~~~~~~
+
+Since {pve} 8.1 the core Software-Defined Network (SDN) packages are installed
+by default.
+
+If you upgrade from an older version, you need to install the
+`libpve-network-perl` package on every node:
 
 ----
 apt update
 apt install libpve-network-perl
 ----
 
-NOTE: {pve} version 7 and above have the `ifupdown2` package installed by
+NOTE: {pve} version 7.0 and above have the `ifupdown2` package installed by
 default. If you originally installed your system with an older version, you need
 to explicitly install the `ifupdown2` package.
-
++
 After installation, you need to add the following line to the end of the
 `/etc/network/interfaces` configuration file, so that the SDN configuration gets
 included and activated.
-
++
 ----
 source /etc/network/interfaces.d/*
 ----
 
+DHCP IPAM
+~~~~~~~~~
 
-[[pvesdn_overview]]
-Overview
---------
+The DHCP integration into the IP Address Management stack currently uses
+`dnsmasq` for giving out DHCP leases. This is currently opt-in.
 
-The {pve} SDN allows for separation and fine-grained control of virtual guest
-networks, using flexible, software-controlled configurations.
+To use that feature you need to install the `dnsmasq` package on every node:
 
-Separation is managed through *zones*, virtual networks (*VNets*), and
-*subnets*.  A zone is its own virtually separated network area.  A VNet is a
-virtual network that belongs to a zone. A subnet is an IP range inside a VNet.
+----
+apt update
+apt install dnsmasq
+----
 
-Depending on the type of the zone, the network behaves differently and offers
-specific features, advantages, and limitations.
+FRRouting
+~~~~~~~~~
 
-Use cases for SDN range from an isolated private network on each individual node
-to complex overlay networks across multiple PVE clusters on different locations.
+The {pve} SDN stack uses the https://frrouting.org/[FRRouting] project for
+advanced setups. This is currently opt-in.
 
-After configuring an VNet in the cluster-wide datacenter SDN administration
-interface, it is available as a common Linux bridge, locally on each node, to be
-assigned to VMs and Containers.
+To use the SDN routing integration you need to install the `frr-pythontools`
+package on all nodes:
 
+----
+apt update
+apt install frr-pythontools
+----
 
 [[pvesdn_main_configuration]]
-Main Configuration
-~~~~~~~~~~~~~~~~~~
+Configuration Overview
+----------------------
 
 Configuration is done at the web UI at datacenter level, separated into the
 following sections:
@@ -86,12 +147,11 @@ in your SDN setup.
   guests
 
 * xref:pvesdn_config_dns[DNS]: Define a DNS server integration for registering
-  virtual guests' hostname and IP
-  addresses
+  virtual guests' hostname and IP addresses
 
 [[pvesdn_tech_and_config_overview]]
 Technology & Configuration
-~~~~~~~~~~~~~~~~~~~~~~~~~~
+--------------------------
 
 The {pve} Software-Defined Network implementation uses standard Linux networking
 as much as possible. The reason for this is that modern Linux networking