You have to be a little careful here because of the limitation on the protocol the Ignition OPC UA driver supports.
To my knowledge, the Ignition OPC UA driver supports only EtherNet/IP to PLC-5E, SLC-5/05, and MicroLogix 1100/1400 controllers.
Ignition's OPC UA server does not have a driver for DF1 Full Duplex, whether with a physical or virtual serial port.
From what I read on the website, the DataLink device cited by FLAEngineer runs as a virtual serial port, providing a DF1 Full Duplex connection over TCP/IP.
The 1761-NET-ENI natively converts the A-B EtherNet/IP protocol to DF1. The client device thinks it is connected to an Ethernet-equipped controller. This works with the Ignition OPC-UA data server.
The Digi One IAP can also do this. It is generally more stable and more powerful than the 1761-NET-ENI, though it is more complicated to configure.
Both the 1761-NET-ENI (Series D and later) and the Digi One IAP have the ability to work like a general-purpose virtual serial port, but they are usually not used for that purpose because they intentionally have the more specialized EtherNet/IP to DF1 conversion functionality.
There may be versions of the DataLink device that truly natively convert EtherNet/IP to DF1 and work with Ignition or with the EtherNet/IP driver in RSLinx Classic.
That DataLink device is sold by two (or more !) different companies using similar brand names and multiple websites with intentionally confusing logos and product descriptions. There's some drama in its history, and the intentional confusion carries over to the technical documentation. I cannot figure out which devices really are aware of the EtherNet/IP protocol, and which ones are implementing a virtual serial port.