When testing remote.phar at the command line for connectivity (with the --test action), I get the following error message:
"Error #36 - We cannot find a way to connect to your server. It seems that your server is incompatible with Akeeba Remote Control CLI."
I tested with Remote CLI 1.2 and 2.1.1 and the behavior was the same for both.
My Joomla sites are running on a couple of webservers behind a load balancer, and my initial thought was someone in our IT department changed a setting without letting me know. But, upon checking, they confirmed they did not make any networking or other kinds of changes to the load balancer. I also tested on my Dev server and, strangely, am getting the same error message there too - it was working there previously like prod. Seems odd that it would suddenly stop working after working well for a couple of years.
Information about my setup:
PHP 7.2.25
PHP-CLI 7.2.25
Apache 2.4.6
Akeeba Backup 7.1.0
I read several, previous tickets submitted about this error message, but the resolutions did not seem applicable. For example, I haven't installed any SEF plugins.