=====
Nodes
=====

**Nodes** represent the physical and virtual devices running the SD-WAN routing
software. All nodes run the same software and can perform the same SD-WAN
functions, regardless of their position in the network. This means that a given
node can act as a client, a concentrator, or both at the same time.

Nodes form tunnel connections to one another via **peers**. Peers consist of
one or more network links and facilitate the bulk of SD-WAN function. More
information on peers can be found in the `peer documentation
<../peers/index.html>`__.

Node configuration is handled solely via the management web UI. Nodes can be
configured with any number of interfaces, addresses, or peers, and can use VRF
to allow multiple routing tables to exist within a single router. Nodes can
also be added to one or more node "groups", allowing for configurations that
apply to multiple nodes at once. Furthermore, access rules can be handled on a
node or node group level. For more information on node groups and access rules,
see the `node group documentation <../node-groups/index.html>`__ and `access rules
documentation <../access-rules/index.html>`__.

Nodes use a local MQTT broker to maintain a connection with the management
server via the orchestration mesh. The local agent is responsible for tracking
and applying any configurations it receives from the manager. More on MQTT and
the node agent can be found in the `architecture documentation
<../architecture.html>`__.

Proceed through the following links to learn about installing and setting up
nodes, managing node records, upgrading nodes, and using node command line
tools.

.. toctree::
    :glob:
    :maxdepth: 1

    installation-and-setup/index
    node-management/index
    upgrading-nodes
    cli