I got the exact error when I turned on SSL for NIFI. In NIFI - Cluster, it shows the nifi service on 9090 port and on 9091 port. The 9090 connection is not able to connect because this port is switched to 9091. There is a button to delete the connection, but I haven't tried it yet so far. Did you make any progress on this issue? Thanks a lot! ... View more