TLS handshake failed: An illegal TLS extension was received: Could provide more info?

Local System Description

• Client (OS name and version): xubuntu 18.10
• Remmina version ( remmina --version ): 1.2.31.4
• Installation mean:
  • Distribution package.
  • PPA.
  • Snap.
  • Flatpak. (I think!)
  • Compiled from sources.
  • Other - detail:
• Desktop environment (GNOME, Unity, KDE, ..):
• Plugin:
  • RDP - freerdp version ( xfreerdp --version ):
  • VNC
  • SSH
  • SFTP
  • SPICE
  • EXEC
  • Other (Please specify):
• Gtk Backend (Wayland, Xorg, ??): X11
• Optional: include the output of the following commands at the end of this text:

  • remmina --full-version (remmina:9124): Gtk-WARNING **: 09:45:31.132: Theme parsing error: gtk.css:123:31: The :insensitive pseudo-class is deprecated. Use :disabled instead. [Also gtk.css:124:24 156:27 157:29 177:34 & 199:34] StatusNotifier/Appindicator support: your desktop does support it and libappindicator is compiled in remmina. Good! Remmina - 1.2.31.4 (git n/a) NAME TYPE DESCRIPTION PLUGIN AND LIBRARY VERSION RDP Protocol RDP - Remote Desktop Protocol RDP Plugin: 1.2.31.4 (git n/a), Compiled with FreeRDP lib: 2.0.0-rc2 (n/a), Running with FreeRDP lib: 2.0.0-rc2 (rev n/a), H264: No RDPF File RDP - RDP File Handler RDP Plugin: 1.2.31.4 (git n/a), Compiled with FreeRDP lib: 2.0.0-rc2 (n/a), Running with FreeRDP lib: 2.0.0-rc2 (rev n/a), H264: No RDPS Preference RDP - Preferences RDP Plugin: 1.2.31.4 (git n/a), Compiled with FreeRDP lib: 2.0.0-rc2 (n/a), Running with FreeRDP lib: 2.0.0-rc2 (rev n/a), H264: No SFTP Protocol SFTP - Secure File Transfer 1.2.31.4
    SSH Protocol SSH - Secure Shell 1.2.31.4
    VNC Protocol VNC - VNC viewer 1.2.31.4
    VNCI Protocol VNCI - VNC viewer listen mode 1.2.31.4
    glibsecret Secret GNOME libsecret 1.2.31.4

  • sudo lshw -C video *-display
    description: VGA compatible controller product: 3rd Gen Core processor Graphics Controller vendor: Intel Corporation physical id: 2 bus info: pci@0000:00:02.0 version: 09 width: 64 bits clock: 33MHz capabilities: msi pm vga_controller bus_master cap_list rom configuration: driver=i915 latency=0 resources: irq:30 memory:f0000000-f03fffff memory:e0000000-efffffff ioport:6000(size=64) memory:c0000-dffff

  • uname -a Linux nautilus 4.18.0-21-generic #22-Ubuntu SMP Wed May 15 13:13:21 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

Remote System Description

• Server (OS name and version): xubuntu 19.04
• Special notes regarding the remote system (i.e. gateways, tunnel, etc): DDNS provided by Synology NAS, port forwarding setup correctly.

Problem Description

Hi all, thank you so much for the work you've done on this program. I'm not very good with this stuff but after some wrangling have managed to set it up and it's already been incredibly useful. So: thanks again! I'm trying to dial into my remote machine by booting it up from a command in my NAS which sends a WOL packet to the machine on the same LAN. However, since I'm remote, I don't know with certainty that the WOL worked, so the machine might be off, and I have no way to tell. My Remmina setup has worked before so I presume (but don't know 100%) that the unchanged settings should be correct. I've tried to WOL and Remmina in with VNC but am getting the TLS handshake failed problem. Reading about this here, it occurs to me that some/many of the possible reasons for this error are not likely or even impossible (?) when Remmina is taking care of much of the config. Would it be possible for this error to be more informative regarding the actual problem? Or is that outside of the scope of TLS? If it could instead say:

• The remote computer did not respond
• The remote computer has a different system time
• (etc etc)

That would be incredibly helpful in allowing users to diagnose their problems. For my example, I presume if my machine is off, "An illegal TLS extension was received" actually means "NO TLS extension was received"?

The external tools are informative however. NSlookup: "server can't find myservername:5900: NXDOMAIN". Ping: "myservername:5900: Name or service not known" If I just punch "myservername:5900" into a browser it returns: RFB 003.007 which apparently means unknown server

Thanks in advance.