My 2016 SharePoint farm, among other servers/services, runs two Front Ends and has Business Data Connectivity setup. I have created an external data source to a SQL server database and an External Content Type via SharePoint Designer. With that, I have created an External List on a site. The two front ends are load balanced.
On one FrontEnd, I can access the external list data by navigating to it in the browser. However, when I am load-balanced to the other Front End, I get the error “A connection was successfully established with the server, but then an error occurred during the login process.” with a further message in the ULS logs saying “The certificate chain was issued by an authority that is not trusted”. I have compared the certificates, trusted and otherwise on both front ends and the SQL servers. Everything appears in order. I have ensured both front end’s bindings are correct to the appropriate sites.
I can’t seem to figure out why when load-balanced to one front end it works, but refuses to work on the other. I’m wondering if there is some web.config item that is off or if there is a registry setting messed up somewhere. Has anyone see this or had experience with this in general?