Just to add some weight to this setup, the following technote outlines the intended usage of the 1769-AENTR Ethernet adapter...
569101 - 1769-AENTR: Features & Firmware Requirements
Access Level: Everyone
As with all the AENT(R) adapters, they may be used to add standalone distributed I/O as an extension of an existing system, or they may be used to replace an existing processor of the same architecture in order to convert the chassis into distributed I/O for another controller.
Simple example:
A 1769-L32E CompactLogix chassis with several digital I/O modules. In order to convert this standalone chassis configuration, and bring the I/O under the direct control of another Logix processor, such as a 1756-L72 ControlLogix, the 1769-L32E processor may be replaced by a 1769-AENTR Ethernet adapter. This way, we can leave all the I/O on the 1769 CompactLogix architecture intact. To reiterate Ken's comment, the 1769-AENTR may then be added to the I/O Configuration of any v20 or newer supported Logix 5000 controller.
The 1769-AENTR also supports up to 30 I/O modules over 3 x I/O banks and, as far as I am aware, supports all 1769 I/O and third party modules.
For Device Level Ring, they are of course fully compatible in a DLR topology with any Logix 5000 controller, including the 1756 ControlLogix architecture...
If I had to answer the original question at the simplest level, and if I did not know that much about the 1769-AENTR Ethernet adapter, I would be pointing out the fact that the much older 1768-ENBT (1769-L4x) Ethernet adapter is fully supported on the 1756 ControlLogix platform. As such, I would be wagering heavily that the newer 1769-AENTR adapter would likewise be also fully supported.
One caveat - you can have only one Owner Connection from a controller to the 1769-AENTR. It does not support Listen Only Connections to multiple controllers.
On the Connections side of things, the 1769-AENTR supports up to 96 TCP Connections. As the adapter does not support Rack Optimization, each module, up to a maximum of 30 I/O modules, will consume one Connection each back to the Owner controller. Here, the adapter itself has plenty of Connections to handle this, but you must make sure the Owner controller also has enough Connections. For most newer Logix 5000 controllers this should not be an issue as they all have increased Connection counts. But still, it should be checked.
If using an older Logix 5000 controller as the Owner controller, such as a 1769-L32E CompactLogix; it supports 100 Connections in total (I'll explain that if somebody wishes) but only 32 TCP "remote" Connections. A full compliment of 30 x 1769 distributed I/O modules under a 1769-AENTR adapter would essentially max out this controllers TCP Connection count, leaving it "nearly" impossible to connect a workstation computer to go online. So I would not say this adapter, when used with a large I/O module count, is suitable for distributed use back to any of these older and Connection limited controllers.
In a modern Logix 5000 controller system though, it should work with little to no problems.
Regards,
George