Cannot connect to ArcGIS Server via ArcMap

[MKF62]

I'm using ArcGIS Desktop 10.7.1 and AGS 10.9.1. This is a federated server.

I have recently installed enterprise using the builder and messed up when putting in the web adaptor so after it installed fully, I unregistered the adaptor with Server and reconfigured a new one. I restarted the AGS at this point. On the new web adaptor installation I chose to disable administrative access, thus I know I need to use a URL with the port number to connect from ArcMap. I have HTTPS enabled on the server and the web adaptor was published to a site with binding 443 (maybe I should have picked the 80 binding version, I don't know). I have entered my fully qualified domain name, plus the port number when trying to create an administrator connection to the GIS Server in ArcMap, but keep getting either error 504 (Proxy server got bad address from remote server) or 500 (generic internal server error). This is the URL I'm using to connect:

https://fullyqualified.domain.com:6443/arcgis

I then enter the primary site administrator account credentials and try to connect with no luck. I have also tried adding /admin onto the end of the above URL; no dice. I have tried every variation I can think of, including using http, 6080, IP address, and the CNAME of the server, but it can't connect. Any suggestions? I wonder if this could just be as simple as a port problem; we opened 7443 for portal and thought that would be enough, but do we need to open 6443 too? I suppose that could make some sense.

I don't think this is relevant, but I can connect to our rest services using our website domain name, so the web adaptor is working properly in that regard. When logged onto the server machine, I can reach manager, admin panel, rest services, etc. using the FQDN + 6443 too.

[JayantaPoddar]

According to Common questions about version compatibility—ArcGIS Server | Documentation for ArcGIS Enterprise,

Can I connect to ArcGIS Server 10.9.1 from ArcMap?

Yes, you can add a user connection or publisher connection from any currently supported version of ArcMap to any currently supported version of ArcGIS Server.

However, with the deprecation of publishing services from ArcGIS Desktop to ArcGIS Server 10.9.1, it's recommended that you do not publish new services from ArcGIS Desktop and that you begin migrating existing services to the ArcGIS Pro service runtime.

After the 10.9.x release cycle, adding publisher connections from ArcMap will not be supported.

Can I administer ArcGIS Server 10.9.1 using a ArcMap?

No, ArcGIS Server 10.9.1 cannot be administered using ArcMap. This is because the ability to administer ArcGIS Server from ArcMap required the two components be at the same release version. Consider using the ArcGIS Server Manager web app to administer your server site.

Can I publish a service to ArcGIS Server 10.9.1 from ArcGIS Desktop?

Generally, yes.

If you're publishing a geoprocessing service, the ArcGIS Desktop version must match ArcGIS Server.

Learn more about geoprocessing service compatibility

However, publishing GIS services from ArcGIS Desktop to ArcGIS Server 10.9.x is deprecated. After the 10.9.x release cycle, publishing services from ArcGIS Desktop won't be supported. It's recommended that you do not publish new services from ArcGIS Desktop and that you begin migrating existing services to the ArcGIS Pro service runtime.

Editing data store properties during publishing is considered an administrative process, which has compatibility limitations.

[MKF62]

Okay, well, I tried connecting as a user and a publisher and it still doesn't work, so there's obviously still something weird going on.

[DavidHoy · Accepted solution]

Hi Molly,

I would suggest you were correct with your thought about ports. To access port :6443, it does need to be allowed through the firewall protecting your server. (when you are actually logged on to the server, you don't need to traverse the firewall).
By using this port you are bypassing the web adaptor altogether.
You may also find you have SSL problems if your ArcGIS Server has not had a certificate installed that matches your FQDN (or other CNAME address you try to use in the URL).
If only going via Web Adaptor, the binding you made to 443 is for the certificate you installed on IIS. This is not used by the AGS site which has its own certificate (by default a self-signed one)
You can add a CA or Domain signed certificate using Configure ArcGIS Server with an existing CA-signed certificate—ArcGIS Server | Documentation for Arc... The certificate can be the same .pfx you installed to IIS for the Web Adaptors (if on the same machine)