@girish many thanks for the advice I did as you asked and I could not telnet to the server via the terminal app, so I then went to the cloudron server and tried it from there it would also not work, which lead me down a bit of rabbit hole 
Eventually I managed to find and issue with the virtual nic on the server itself and managed to resolve that, and now it is working perfectly.
Not sure how I missed it but you helped me find so many thanks.
Kind Regards
Scott
If this help here is a snippet of the log file as I am connecting to one of my machines:
Nov 23 10:49:52 guacd[20]: INFO: Creating new client for protocol "rdp"
Nov 23 10:49:52 guacd[20]: INFO: Connection ID is "$917240f9-15a6-42da-b0ac-6c1079935e71"
Nov 23 10:49:52 guacd[294]: DEBUG: Processing instruction: size
Nov 23 10:49:52 guacd[294]: DEBUG: Processing instruction: audio
Nov 23 10:49:52 guacd[294]: DEBUG: Processing instruction: video
Nov 23 10:49:52 guacd[294]: DEBUG: Processing instruction: image
Nov 23 10:49:52 guacd[294]: DEBUG: Processing instruction: timezone
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "console" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "console-audio" omitted. Using default value of 0.
Nov 23 10:49:52 10:49:52.582 [http-nio-8080-exec-3] INFO o.a.g.tunnel.TunnelRequestService - User "guacadmin" connected to connection "7".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "disable-auth" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: INFO: Security mode: NLA
Nov 23 10:49:52 guacd[294]: DEBUG: User resolution is 2560x1287 at 96 DPI
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "dpi" omitted. Using default value of 96.
Nov 23 10:49:52 guacd[294]: DEBUG: Using resolution of 2560x1287 at 96 DPI
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "read-only" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "client-name" omitted. Using default value of "Guacamole RDP".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "enable-wallpaper" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "enable-theming" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "enable-font-smoothing" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "enable-full-window-drag" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "enable-desktop-composition" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "enable-menu-animations" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "disable-bitmap-caching" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "disable-offscreen-caching" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "disable-glyph-caching" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "color-depth" omitted. Using default value of 16.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "disable-audio" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "enable-printing" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "printer-name" omitted. Using default value of "Guacamole Printer".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "enable-drive" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "drive-name" omitted. Using default value of "Guacamole Filesystem".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "drive-path" omitted. Using default value of "".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "create-drive-path" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "disable-download" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "disable-upload" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "timezone" omitted. Using default value of "Europe/London".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "enable-sftp" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "sftp-hostname" omitted. Using default value of "[ip of machine]".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "sftp-port" omitted. Using default value of "22".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "sftp-username" omitted. Using default value of "[username]".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "sftp-password" omitted. Using default value of "".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "sftp-passphrase" omitted. Using default value of "".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "sftp-root-directory" omitted. Using default value of "/".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "sftp-server-alive-interval" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "sftp-disable-download" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "sftp-disable-upload" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "recording-name" omitted. Using default value of "recording".
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "recording-exclude-output" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "recording-exclude-mouse" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "recording-include-keys" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "create-recording-path" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: INFO: Resize method: none
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "enable-audio-input" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "gateway-port" omitted. Using default value of 443.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "disable-copy" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "disable-paste" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: DEBUG: Parameter "wol-send-packet" omitted. Using default value of 0.
Nov 23 10:49:52 guacd[294]: INFO: User "@352f1f87-cfe2-467d-970a-ce83867f6d11" joined connection "$917240f9-15a6-42da-b0ac-6c1079935e71" (1 users now present)
Nov 23 10:49:52 guacd[294]: DEBUG: Client is using protocol version "VERSION_1_3_0"
Nov 23 10:49:52 guacd[294]: INFO: Loading keymap "base"
Nov 23 10:49:52 guacd[294]: INFO: Loading keymap "en-us-qwerty"
Nov 23 10:49:52 guacd[294]: DEBUG: freerdp_connect:freerdp_set_last_error_ex resetting error state
Nov 23 10:49:52 guacd[294]: DEBUG: Support for CLIPRDR (clipboard redirection) registered. Awaiting channel connection.
Nov 23 10:49:52 guacd[294]: DEBUG: Support for static channel "rdpdr" loaded.
Nov 23 10:49:52 guacd[294]: DEBUG: Support for static channel "rdpsnd" loaded.
Nov 23 10:49:52 guacd[294]: DEBUG: Local framebuffer format PIXEL_FORMAT_BGRX32
Nov 23 10:49:52 guacd[294]: DEBUG: Remote framebuffer format PIXEL_FORMAT_RGB16
Nov 23 10:49:52 guacd[294]: DEBUG: primitives autodetect, using optimized
Nov 23 10:49:52 guacd[294]: DEBUG: freerdp_tcp_is_hostname_resolvable:freerdp_set_last_error_ex resetting error state
Nov 23 10:49:52 guacd[294]: DEBUG: freerdp_tcp_connect:freerdp_set_last_error_ex resetting error state
Nov 23 10:50:07 guacd[294]: DEBUG: freerdp_tcp_connect:freerdp_set_last_error_ex ERRCONNECT_CONNECT_FAILED [0x00020006]
Nov 23 10:50:07 guacd[294]: DEBUG: failed to connect to [IP Address of Machine]
Nov 23 10:50:07 guacd[294]: DEBUG: SVC "rdpdr" disconnected.
Nov 23 10:50:07 guacd[294]: DEBUG: SVC "rdpsnd" disconnected.
Nov 23 10:50:07 guacd[294]: INFO: RDP server closed/refused connection: Connection failed (server unreachable?)
Nov 23 10:50:07 guacd[294]: INFO: User "@352f1f87-cfe2-467d-970a-ce83867f6d11" disconnected (0 users remain)
Nov 23 10:50:07 guacd[294]: INFO: Last user of connection "$917240f9-15a6-42da-b0ac-6c1079935e71" disconnected
Nov 23 10:50:07 guacd[294]: DEBUG: Requesting termination of client...
Nov 23 10:50:07 10:50:07.991 [http-nio-8080-exec-4] INFO o.a.g.tunnel.TunnelRequestService - User "guacadmin" disconnected from connection "7". Duration: 15409 milliseconds
Nov 23 10:50:07 guacd[294]: DEBUG: Client terminated successfully.
Nov 23 10:50:07 Exception in thread "Thread-18" java.lang.IllegalStateException: Message will not be sent because the WebSocket session has been closed
Nov 23 10:50:07 at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.writeMessagePart(WsRemoteEndpointImplBase.java:430)
Nov 23 10:50:07 at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendMessageBlock(WsRemoteEndpointImplBase.java:309)
Nov 23 10:50:07 at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendMessageBlock(WsRemoteEndpointImplBase.java:250)
Nov 23 10:50:07 at org.apache.tomcat.websocket.WsRemoteEndpointImplBase.sendString(WsRemoteEndpointImplBase.java:191)
Nov 23 10:50:07 at org.apache.tomcat.websocket.WsRemoteEndpointBasic.sendText(WsRemoteEndpointBasic.java:37)
Nov 23 10:50:07 at org.apache.guacamole.websocket.GuacamoleWebSocketTunnelEndpoint.sendInstruction(GuacamoleWebSocketTunnelEndpoint.java:152)
Nov 23 10:50:07 at org.apache.guacamole.websocket.GuacamoleWebSocketTunnelEndpoint.access$200(GuacamoleWebSocketTunnelEndpoint.java:53)
Nov 23 10:50:07 at org.apache.guacamole.websocket.GuacamoleWebSocketTunnelEndpoint$2.run(GuacamoleWebSocketTunnelEndpoint.java:253)
Nov 23 10:50:07 guacd[20]: INFO: Connection "$917240f9-15a6-42da-b0ac-6c1079935e71" removed.
I have ommited the IP address and username from the snippet for security. but hopefully this should give you some clue perhaps as to what might be happening.
Kind Regards
Scott
@girish hi many thanks for your reply, I am connecting via IP, so not to involve DNS in the equation, because I thought that might cause an issue.
Hello all,
first and foremeost thank you for the amazing app you have provided on the clouron platform.
I have just one annoying issue, and that is I can RDP to some of my machines, but others I cannot, the machines are on the same network so I am not sure what is going on. The machine that I cannot connect to just timeout.
I have checked all the obvious things on the machines themselves but they are fine I can RDP them normally not using Guac so I am at a loss.
The only thing pattern I can see is that the clouron is installed on my VMWare host, and the machines I can RDP on to are also on that host, where as the machines I cannot are physical machines, not virtual machines.
I would not have thought that would be an issue but one of you amazing guru's maybe will know if it is.
Any help will be gratefully received.
Many thanks in advance
Scott