AI Node as Network Bridge

Connecting AI Node with Skynode while exposing additional Ethernet port

Before proceeding, make sure you have interconnected AI Node and Skynode.

By default, when AI Node is connected to Skynode, Skynode's ethernet port is occupied, and other ethernet peripherials such as radios cannot be connected. In order to bypass that limitation, AI Node may be configured as bridge, allowing its second ethernet port to be used as Skynodes port.

Once AI Node was connected to Skynode via ETH0, connect required peripheral, in this example Microhard radio module, to ETH1 of AI Node. The setup should look like following:

Configuration of the Ethernet Bridge

Refer to the following page for details on how to store Environment Variables in AuterionOS.

Modifying Environment Variables

Login to AI Node via any of the available developers methods. In order to enable bridge mode, a number of Environment variables has to be set on AI Node side:

# Enable the Ethernet bridge
AINODE_ETHERNET_BRIDGE_ENABLE=1
# IP address of bridge interface
AINODE_CONFIGURE_ETHERNET_BRIDGE_IP=172.20.50.50
AINODE_CONFIGURE_ETHERNET_BRIDGE_MASK=255.255.0.0

On older versions of AOS:

• Less than v2.7.3 for Skynode

• Less than ainode-v0.7.0 for AI Node

Environment variables prefixed AINODE_ shall be NVIDIA_ instead

172.20.50.50 represents the IP of AI Node. The IP address has to lie in the same subnet as Skynode. AI Node is accessible from Skynode by this static IP address.

Once configured, AI Node will act like network switch, with IP address forwarding enabled. In this mode, any device attached to ETH1 of AI Node can be accessed directly by its IP from Skynode.

If you added the environment variables to /data/override.env, power-cycle device afterwards for the changes to take effect

Example Configuration with Internet Sharing

The following example configuration works with Skynode's Internet Sharing and provides update capabilities through the local web server.

To achieve that, combine above mentioned configutation, with configurations from Internet sharing with Skynode, and use one of the subnet which can be used for local updates.

Configuration on AI Node:

Following changes are requirerd to enable bridge mode, and receive internet from Skynode

# Enable the Ethernet bridge
AINODE_ETHERNET_BRIDGE_ENABLE=1
# Subnet which is whitelisted for accepting local updates
AINODE_CONFIGURE_ETHERNET_BRIDGE_IP=172.20.50.50
AINODE_CONFIGURE_ETHERNET_BRIDGE_MASK=255.255.0.0

# Use Skynode as the default gateway
DEFAULT_GATEWAY=172.20.110.10

Configuration on Skynode:

Following changes are required to enable internet sharing

# Enable routing
INTERNET_FORWARD=1

# Must match DEFAULT_GATEWAY specified on AI Node
AP_CONFIGURE_ETHERNET_IP=172.20.110.10

# Must match the prefix of AI Node's network configuration
AP_CONFIGURE_ETHERNET_IP_PREFIX=16

# Must match `AINODE_CONFIGURE_ETHERNET_BRIDGE_IP` on AI Node
AINODE_ETH_IP=172.20.50.50

Example Configuration for use with Microhard Radios

If Microhard Radios are being used, the AI Node's IP address must be within the subnet 192.168.168.0/24, as this is the default configuration of the Radios.

Example configuration then could be as following:

Configuration on AI Node:

# Enable the Ethernet bridge
AINODE_ETHERNET_BRIDGE_ENABLE=1
# IP addresss of Microhard subnet, which is not one of the reserved addresses
AINODE_CONFIGURE_ETHERNET_BRIDGE_IP=192.168.168.99
AINODE_CONFIGURE_ETHERNET_BRIDGE_MASK=255.255.255.0

In case of Microhard radios, AI Node IP address cannot be any of the following addresses, as these are reserved for being assigned to air/ground units:

• 192.168.168.1

• 192.168.168.2

• 192.168.168.10

• 192.168.168.20-39

• 192.168.168.100

To confirm successfull setup, make sure the radio is visible from Skynode, eg. by pinging its default IP address of 192.168.168.2. You may now proceed with pairing sequence as usual as described in the Microhard Data Link guide.

The caveat when using this configuration is that installing AuterionOS images via this particular network connection will not be possible. In particular:

• Skynode won't be able to forward AuterionOS updates on this network interface

• You won't be able to install updates by visiting the web UI through this network interface

This limitation can be avoided by using the "standard" IP settings as shown in the next example. Updates via USB, update via Suite are also not affected.