Option to specify secondary Office server in farm

[robake1]

When using a Microsoft Office Online server with two or more member servers we want to specify primary and secondary server instead of using DNS round robin or a Load Balancer.

An option in the GUI or OCC to add URL to a second Office Online server , to be sure the Office Online app work against both servers in Office Online farm. For example if server 1 is down it connects to server 2.

We have tried with a Load Balancer for our Office Online servers but co editing does not show other users working in the document as shown in screenshot below.

If we specify the Office Online server URL directly to the Office Online server co editing works fine.