RDP server closed/refused connection: Server refused connection (wrong security type?)

[dell1503]

Describe the issue: First of all, thank you for the great script! However, I'm currently facing an issue. I have an Ubuntu Desktop 24.04 machine that I want to connect to using Guacamole. I added a new connection in Guacamole, specifically for this purpose (I even set up a new Guacamole Server). Unfortunately, I am unable to connect to the Ubuntu machine through Guacamole. However, I can successfully connect to the same target Ubuntu machine from my Windows machine.

Steps to reproduce the issue:

1. Add a new RDP connection in Guacamole.
2. Provide basic information such as the Target, Port, Username, Password, and check "Ignore server certificate."
3. Experiment with different Security Modes (NLA, Any, TLS, etc.), but none seem to work.
4. Attempt to connect.

Log Output:

Aug 23 09:40:20 dc-terminal guacd[37488]: guacd[37488]: WARNING:        FreeRDP initialization may fail: The current user's home directory ("/usr/sbin") is not writable, but FreeRDP generally requires a writable home directory for storage of configuration files and certificates.
Aug 23 09:40:20 dc-terminal guacd[37488]: Security mode: Negotiate (ANY)
Aug 23 09:40:20 dc-terminal guacd[37488]: Resize method: none
Aug 23 09:40:20 dc-terminal guacd[37488]: guacd[37488]: INFO:        Security mode: Negotiate (ANY)
Aug 23 09:40:20 dc-terminal guacd[37488]: guacd[37488]: INFO:        Resize method: none
Aug 23 09:40:20 dc-terminal guacd[37488]: guacd[37488]: INFO:        No clipboard line-ending normalization specified. Defaulting to preserving the format of all line endings.
Aug 23 09:40:20 dc-terminal guacd[37488]: guacd[37488]: INFO:        User "@1c449a77-fe6c-4aa7-af90-7711f22b539b" joined connection "$923db85b-b7db-422b-a815-fab13f52a472" (1 users now present)
Aug 23 09:40:20 dc-terminal guacd[37488]: No clipboard line-ending normalization specified. Defaulting to preserving the format of all line endings.
Aug 23 09:40:20 dc-terminal guacd[37488]: User "@1c449a77-fe6c-4aa7-af90-7711f22b539b" joined connection "$923db85b-b7db-422b-a815-fab13f52a472" (1 users now present)
Aug 23 09:40:20 dc-terminal guacd[37488]: Loading keymap "base"
Aug 23 09:40:20 dc-terminal guacd[37488]: guacd[37488]: INFO:        Loading keymap "base"
Aug 23 09:40:20 dc-terminal guacd[37488]: guacd[37488]: INFO:        Loading keymap "en-us-qwerty"
Aug 23 09:40:20 dc-terminal guacd[37488]: Loading keymap "en-us-qwerty"
Aug 23 09:40:24 dc-terminal guacd[37488]: RDP server closed/refused connection: Server refused connection (wrong security type?)
Aug 23 09:40:24 dc-terminal guacd[37488]: guacd[37488]: INFO:        RDP server closed/refused connection: Server refused connection (wrong security type?)
Aug 23 09:40:24 dc-terminal guacd[37488]: User "@1c449a77-fe6c-4aa7-af90-7711f22b539b" disconnected (0 users remain)
Aug 23 09:40:24 dc-terminal guacd[37488]: guacd[37488]: INFO:        User "@1c449a77-fe6c-4aa7-af90-7711f22b539b" disconnected (0 users remain)
Aug 23 09:40:24 dc-terminal guacd[37488]: guacd[37488]: INFO:        Last user of connection "$923db85b-b7db-422b-a815-fab13f52a472" disconnected
Aug 23 09:40:24 dc-terminal guacd[37488]: Last user of connection "$923db85b-b7db-422b-a815-fab13f52a472" disconnected
Aug 23 09:40:24 dc-terminal guacd[36559]: Connection "$923db85b-b7db-422b-a815-fab13f52a472" removed.
Aug 23 09:40:24 dc-terminal guacd[36559]: guacd[36559]: INFO:        Connection "$923db85b-b7db-422b-a815-fab13f52a472" removed.
Aug 23 09:40:39 dc-terminal guacd[36559]: Creating new client for protocol "rdp"
Aug 23 09:40:39 dc-terminal guacd[36559]: guacd[36559]: INFO:        Creating new client for protocol "rdp"
Aug 23 09:40:39 dc-terminal guacd[36559]: guacd[36559]: INFO:        Connection ID is "$68888d65-a57a-456d-86b2-23441124bab0"
Aug 23 09:40:39 dc-terminal guacd[36559]: Connection ID is "$68888d65-a57a-456d-86b2-23441124bab0"
Aug 23 09:40:39 dc-terminal guacd[37530]: FreeRDP initialization may fail: The current user's home directory ("/usr/sbin") is not writable, but FreeRDP generally requires a writable home directory for storage of configuration files and certificates.

Describe the software environment:

• Freshly installed Ubuntu Server 24.04
• Freshly installed Guacamole
• Target Machine: Freshly installed Ubuntu Desktop 24.04

Logs / screenshots / error outputs:

• See the log output above.

Troubleshooting steps already taken:

• Tried multiple security types

[itiligent]

The logs look like you are attempting to connect to Ubuntu using RDP. RDP is a Windows protocol, or are you trying to get Free rdp or some other Linux RDP client? This can be a can of worms regarding compatibility. If so look into how to ignore the client certificate .. a good place to start maybe

[dell1503]

Thank you for your assistance.

I switched my approach and installed XRDP on the target machine instead of the default option. After that, it was quite easy to establish the connection.

@itiligent, thank you for the quick reply!