Hi and welcome to Dig Forum!
This would depend on the firmware you currently have on the device. On the old firmware versions, ETH bonding was supported for load balance and network failover: (https://www.digi.com/resources/documentation/digidocs/90002294/default.htm#tasks/t_ethnert_network_bonding.htm?Highlight=bonding).
Now, starting from the new DAL firmware 188.8.131.52 or later, the ETH behavior is changed and the has not been implemented yet currently.
Basically ETH 1 and ETH2 on the old firmware were sharing 1 MAC and 1 IP, instead now, they are independent, each with its MAC and its IP.
The bonding feature will be re-implemented (planned for 20.8 firmware) for any DAL device with 2 or more ETH ports, so that the ports can be bonded and combined into a bonded "device", which can be selected as the target device when creating a network interface.
With that change, the same MAC address and IP address is shared across multiple Ethernet ports, allowing the entire network stack to remain the same regardless of which Ethernet port is utilized to communicate with the device.
In the meantime, one option to achieve Network failover on the new DAL firmware is explained below:
-Enable both ETH1 and ETH2 interfaces under Network→Interfaces
-Under the IPv4 and IPv6 sections of both ETH1 and ETH2 interfaces, set the Metric to the two different values between the two interfaces. The closer the metric value is to zero, the higher priority the Interface has. For example, setting ETH1 with a metric of 1 and ETH2 with a metric of 2 would mean that ETH1 is the primary/active Internet connection and ETH2 is the backup Internet connection that is only utilized if ETH1 is down
-From the user point of view, what will happen is that the AWUSB manager automatically discover the IP of the hub (by default in Preferences > setup > Autofind Hubs is enabled). If you use this, as soon as, for example, ETH 1 interface has a failure, the manager will reconnect to the same hub detecting the secondary IP.
- When the ETH1 goes back into service, as from the manager point of view there is not a connection loss, the manager will keep the connection to the hub using the secondary IP until a failure happens on ETH2 or for example until a reboot occurs
I hope this helps, for any further queries please contact us at firstname.lastname@example.org and/or review our support options https://www.digi.com/support.
Digi Technical Support Team