.. _reference-network-comms-in-cluster:

Network Communications between Nodes within the Cluster
-------------------------------------------------------

The cluster contains multiple nodes which can be contained in separate firewalled networks.
Network ports need to be opened on firewalls to allow inter-node communication.

All communication between nodes is encrypted.

The following details are all based on the default settings. These
can vary depending on the application setup and network design (such as
NAT) of the solution, so may need adjustment accordingly. Where a dependant
is noted, this is fully dependant on the configuration with no default.

These communications are all related to communications between
application nodes within the cluster. There are a few different
deployment models so the details below cover the different models and
relevant ports. So review and implement according to the deployment
model in use.

Note that Standalone is only a single node so this section is not relevant
for that deployment model.

* Proxy to Proxy Node

  This is relevant if the proxy node is present in the system.

  +------------------------+----------+-------------------------+
  | Communication          | Protocol | Port                    |
  +========================+==========+=========================+
  | Cluster Communications | HTTPS    | TCP 8443 bi-directional |
  +------------------------+----------+-------------------------+

* Proxy to Unified/Application Node

  This is relevant if the proxy node is present in the system.

  +------------------------+----------+-------------------------+
  | Communication          | Protocol | Port                    |
  +========================+==========+=========================+
  | User access            | HTTPS    | TCP 443                 |
  +------------------------+----------+-------------------------+
  | Cluster Communications | HTTPS    | TCP 8443 bi-directional |
  +------------------------+----------+-------------------------+

* Unified Node to Unified node

  This is relevant to the communications between the unified nodes
  (application and database combined). If the application and database
  nodes are split, then see the relevant application and database node
  details below. Database arbiters run on port 27030.

  +------------------------+----------+------------------------------------+
  | Communication          | Protocol | Port                               |
  +========================+==========+====================================+
  | Database access        | database | TCP 27020 and 27030 bi-directional |
  +------------------------+----------+------------------------------------+
  | Cluster Communications | HTTPS    | TCP 8443                           |
  +------------------------+----------+------------------------------------+

* Application node to Application node

  This is relevant to the communications between application nodes nodes
  in the system. This is only relevant where the database node is
  separate from the application node (in other words, not Unified node).

  +------------------------+----------+-------------------------+
  | Communication          | Protocol | Port                    |
  +========================+==========+=========================+
  | Cluster communications | HTTPS    | TCP 8443 bi-directional |
  +------------------------+----------+-------------------------+

* Application Node to Database node

  This is relevant to the communications between the application node and
  the database node. This is relevant if the database node is separate
  from the application node. Database arbiters run on port 27030.


  +------------------------+----------+------------------------------------+
  | Communication          | Protocol | Port                               |
  +========================+==========+====================================+
  | Database access        | database | TCP 27020 and 27030 bi-directional |
  +------------------------+----------+------------------------------------+
  | Cluster Communications | HTTPS    | TCP 8443                           |
  +------------------------+----------+------------------------------------+

* Database Node to Database node

  This is relevant to the communications between the application node and
  the database node.  This is relevant if the database node is separate
  from the application node. Database arbiters run on port 27030.

  +------------------------+----------+------------------------------------+
  | Communication          | Protocol | Port                               |
  +========================+==========+====================================+
  | Database access        | database | TCP 27020 and 27030 bi-directional |
  +------------------------+----------+------------------------------------+
  | Cluster Communications | HTTPS    | TCP 8443                           |
  +------------------------+----------+------------------------------------+