Multi OS swarm cannot manage/connect

Hi All,

I’ve got swarm configured with 3 windows hosts and 2 linux hosts. Swarm appears to be healthy. I’m trying to manage this swarm cluster via an external portainer instance. However when I connect I get

Get https://X.X.X.X:2377/_ping: net/http: HTTP/1.x transport connection broken: malformed HTTP response “\x00\x00\x00\x04\x00\x00\x00\x00\x00”

OR

An error relating to EOF

Has anyone setup a basic swarm cluster with external management and come across this issue?