An error "Could not resolve hostname (null) to IPv4" occurs, preventing connection to the server with the IPv6 address.
I have a server with an IPv6 address, and I always connect to the server using IPv6. I use the SSH tunnel function's 'tunnel via loopback address' to connect to the VNC server that I am running. I hadn't been using Remmina for a while, but when I tried to connect to the server today after a long time, I noticed that I couldn't connect to the server because an error message 'Could not resolve hostname (null) to IPv4' was displayed. I should have been able to connect successfully until a little while ago.
The IPv6 addresses are entered as follows. Additionally, for security reasons, the port of the SSH server has been changed from port 22.
VNC Server: [1:2:3:4:5:6]:5900
SSH Server: [1:2:3:4:5:6]:789
I am running Remmina 1.4.35 (git 2a455ead) on Ubuntu 22.04. Remmina was installed from Flatpak.
However, this issue does not occur with the official Ubuntu package version 1.4.25 (git n/a).
What is the expected correct behavior?
Even if I enter an IPv6 address, Remmina should still be able to connect to the server successfully.
Remote System Description
- Server (OS name and version): Debian 12
- Special notes regarding the remote system (i.e. gateways, tunnel, etc.): I am running a VNC server on port 5901, allowing access only from the local machine. I am connecting to VNC via an SSH tunnel.
Relevant logs and/or screenshots
I am replacing the server's IP address in the debug logs with the IPv6 address [1:2:3:4:5:6] and changing the port number to 789.
このウィンドウは接続問題の原因を探すためのものです。
On/Offスイッチでいつでもログの出力を入/切できます。
統計ボタン (Ctrl+T) は、バグ報告で共有するシステム情報の取得に便利です。
https://gitlab.com/Remmina/Remmina/-/wikis/Usage/Remmina-debugging に Remminaのデバッグについて説明されています。
(DEBUG) - (rcw_map_event) - Mapping: RemminaConnectionWindow
(DEBUG) - (remmina_protocol_widget_map_event) - Map plugin function not implemented
(DEBUG) - (remmina_protocol_widget_open_connection_real) - Opening connection
(DEBUG) - (remmina_plugin_vnc_init) - Disable smooth scrolling is set to 0
(DEBUG) - (remmina_plugin_vnc_init) - Adding GDK_SMOOTH_SCROLL_MASK
(DEBUG) - (remmina_protocol_widget_open_connection_real) - Have SSH
(DEBUG) - (remmina_protocol_widget_start_direct_tunnel) - SSH tunnel initialization…
(DEBUG) - (remmina_plugin_vnc_open_connection) - [2024-04-16T02:01:53.572343+09] - clientpc - user - VNC で 1:2:3:4:5:6:5900 に接続
(DEBUG) - (remmina_protocol_widget_start_direct_tunnel) - Calling remmina_public_get_server_port
(DEBUG) - (remmina_protocol_widget_start_direct_tunnel) - Calling remmina_public_get_server_port (tunnel)
(DEBUG) - (remmina_protocol_widget_start_direct_tunnel) - server: 1:2:3:4:5:6, port: 5900
(DEBUG) - (remmina_ssh_init_from_file) - We are initializing an SSH tunnel session
(DEBUG) - (remmina_ssh_init_from_file) - Calling remmina_public_get_server_port
(DEBUG) - (remmina_ssh_init_from_file) - server:port = 1:2:3:4:5:6:789, server = 1:2:3:4:5:6:1234, port = 22
(DEBUG) - (remmina_ssh_init_from_file) - Initialized SSH struct from file with ssh->server = 1:2:3:4:5:6:1234 and SSH->port = 22
(DEBUG) - (remmina_ssh_init_from_file) - ssh->user: root
(DEBUG) - (remmina_ssh_init_from_file) - ssh->password: (null)
(DEBUG) - (remmina_ssh_init_from_file) - ssh->auth: 1
(DEBUG) - (remmina_ssh_init_from_file) - ssh->charset: (null)
(DEBUG) - (remmina_ssh_init_from_file) - ssh->kex_algorithms: (null)
(DEBUG) - (remmina_ssh_init_from_file) - ssh->ciphers: (null)
(DEBUG) - (remmina_ssh_init_from_file) - ssh->hostkeytypes: (null)
(DEBUG) - (remmina_ssh_init_from_file) - ssh->proxycommand: (null)
(DEBUG) - (remmina_ssh_init_from_file) - ssh->stricthostkeycheck: 0
(DEBUG) - (remmina_ssh_init_from_file) - ssh->compression: no
(DEBUG) - (remmina_ssh_init_from_file) - ssh->privkeyfile: /home/user/.ssh/private-key
(DEBUG) - (remmina_protocol_widget_init_tunnel) - Creating SSH tunnel to “1:2:3:4:5:6:789” via SSH…
(DEBUG) - (remmina_ssh_init_session) - server=1:2:3:4:5:6:789 port=22 is_tunnel=Yes tunnel_entrance_host=(null) tunnel_entrance_port=0
(DEBUG) - (remmina_ssh_init_session) - Setting SSH_OPTIONS_HOST to 1:2:3:4:5:6:789 and SSH_OPTIONS_PORT to 22
(DEBUG) - (remmina_ssh_init_session) - SSH_OPTIONS_IDENTITY is now /home/user/.ssh/private-key
(DEBUG) - (remmina_ssh_log_callback) - ssh_options_parse_config: Invalid argument in ssh_options_parse_config
(DEBUG) - (remmina_ssh_init_session) - Cannot parse ssh_config: Invalid argument in ssh_options_parse_config
(DEBUG) - (remmina_ssh_init_session) - SSH_OPTIONS_USER is now root
(DEBUG) - (remmina_ssh_init_session) - Parsing ssh_config for SSH_OPTIONS_PROXYCOMMAND returned an error: Invalid argument in ssh_options_parse_config
(DEBUG) - (remmina_ssh_log_callback) - ssh_options_set: Invalid argument in ssh_options_set
(DEBUG) - (remmina_ssh_init_session) - SSH_OPTIONS_PROXYCOMMAND does not have a valid value. (null)
(DEBUG) - (remmina_ssh_log_callback) - ssh_options_get: Unknown ssh option 1
(DEBUG) - (remmina_ssh_init_session) - Parsing ssh_config for SSH_OPTIONS_HOSTKEYS returned an error: Unknown ssh option 1
(DEBUG) - (remmina_ssh_log_callback) - ssh_options_set: Invalid argument in ssh_options_set
(DEBUG) - (remmina_ssh_init_session) - SSH_OPTIONS_HOSTKEYS does not have a valid value. (null)
(DEBUG) - (remmina_ssh_log_callback) - ssh_options_get: Unknown ssh option 2
(DEBUG) - (remmina_ssh_init_session) - Parsing ssh_config for SSH_OPTIONS_KEY_EXCHANGE returned an error: Unknown ssh option 2
(DEBUG) - (remmina_ssh_log_callback) - ssh_options_set: Invalid argument in ssh_options_set
(DEBUG) - (remmina_ssh_init_session) - SSH_OPTIONS_KEY_EXCHANGE does not have a valid value. (null)
(DEBUG) - (remmina_ssh_log_callback) - ssh_options_get: Unknown ssh option 3
(DEBUG) - (remmina_ssh_init_session) - Parsing ssh_config for SSH_OPTIONS_CIPHERS_C_S returned an error: Unknown ssh option 3
(DEBUG) - (remmina_ssh_log_callback) - ssh_options_set: Invalid argument in ssh_options_set
(DEBUG) - (remmina_ssh_init_session) - SSH_OPTIONS_CIPHERS_C_S does not have a valid value. (null)
(DEBUG) - (remmina_ssh_log_callback) - ssh_options_get: Unknown ssh option 4
(DEBUG) - (remmina_ssh_init_session) - Parsing ssh_config for SSH_OPTIONS_STRICTHOSTKEYCHECK returned an error: Unknown ssh option 4
(DEBUG) - (remmina_ssh_init_session) - SSH_OPTIONS_STRICTHOSTKEYCHECK is now 0
(DEBUG) - (remmina_ssh_log_callback) - ssh_options_get: Unknown ssh option 5
(DEBUG) - (remmina_ssh_init_session) - Parsing ssh_config for SSH_OPTIONS_COMPRESSION returned an error: Unknown ssh option 5
(DEBUG) - (remmina_ssh_init_session) - SSH_OPTIONS_COMPRESSION is now no
(DEBUG) - (remmina_ssh_log_callback) - ssh_connect: Hostname required
(DEBUG) - (remmina_ssh_init_session) - Could not resolve hostname (null) to IPv6
(DEBUG) - (remmina_ssh_init_session) - Could not resolve hostname (null) to IPv4
(DEBUG) - (remmina_protocol_widget_init_tunnel) - SSH Tunnel init session error: Could not resolve hostname (null) to IPv4
(DEBUG) - (remmina_ssh_tunnel_free) - tunnel->thread = 0
(DEBUG) - (remmina_ssh_free) - Disconnecting SSH session
(DEBUG) - (remmina_protocol_widget_start_direct_tunnel) - remmina_protocol_widget_init_tunnel failed with error is Could not resolve hostname (null) to IPv4
(DEBUG) - (remmina_plugin_vnc_main) - host is null
(DEBUG) - (remmina_plugin_vnc_main) - Client not connected with error:
(DEBUG) - (rco_on_disconnect) - Disconnect signal received on RemminaProtocolWidget
(DEBUG) - (remmina_file_save) - Saving profile
(DEBUG) - (remmina_file_save) - We have a secret and disablepasswordstoring=0
(DEBUG) - (remmina_plugin_glibsecret_store_password) - Password “password” saved for file /home/user/.var/app/org.remmina.Remmina/data/remmina/group_vnc_サーバー_[1-2-3-4-5-6]-5900.remmina
(DEBUG) - (remmina_file_save) - We have a secret and disablepasswordstoring=0
(DEBUG) - (remmina_plugin_glibsecret_delete_password) - password “ssh_tunnel_password” deleted for file /home/user/.var/app/org.remmina.Remmina/data/remmina/group_vnc_サーバー_[1-2-3-4-5-6]-5900.remmina
(DEBUG) - (remmina_file_save) - We have a secret and disablepasswordstoring=0
(DEBUG) - (remmina_plugin_glibsecret_delete_password) - password “ssh_tunnel_passphrase” deleted for file /home/user/.var/app/org.remmina.Remmina/data/remmina/group_vnc_サーバー_[1-2-3-4-5-6]-5900.remmina
(DEBUG) - (remmina_file_save) - Profile saved
(DEBUG) - (remmina_file_save) - Connection profile states saved
(DEBUG) - (remmina_network_monitor_status) - G_NETWORK_CONNECTIVITY_FULL
(DEBUG) - (rco_on_disconnect) - Could not disconnectDebugging documentation
Please see Remmina debugging
Local System Description
-
Client (OS name and version): Kubuntu 22.04.4 LTS x86_64
-
Remmina version (
remmina --version): 1.4.35 (git 2a455ead) -
Installation(s):
-
Distribution package. -
PPA. -
Snap. -
Flatpak. -
Compiled from sources. -
Other - detail:
-
-
Desktop environment (GNOME, Unity, KDE, ..): KDE
-
Plugin(s):
-
RDP - freerdp version ( xfreerdp --version): -
VNC -
SSH -
SFTP -
SPICE -
WWW -
EXEC -
Other (please specify):
-
-
GTK backend (Wayland, Xorg): Xorg
-
Optional: Include the output of the following commands at the end of this text:
remmina --full-version
remmina-Message: 01:57:53.563: Remmina does not log all output statements. Turn on more verbose output by using "G_MESSAGES_DEBUG=remmina" as an environment variable.
More info available on the Remmina wiki at:
https://gitlab.com/Remmina/Remmina/-/wikis/Usage/Remmina-debugging
org.remmina.Remmina - 1.4.35 (git 2a455ea)
NAME TYPE DESCRIPTION PLUGIN AND LIBRARY VERSION
EXEC Protocol Execute a command 1.0
GVNC Protocol Remmina VNC plugin for GNOME and KVM 0.1b
Python Wrapper Language WrapperEnables Python plugins for Remmina Python Wrapper for Remmina v0.1
RDP Protocol RDP - Remote Desktop Protocol RDP plugin: 1.4.35 (Git 2a455ea), Compiled with libfreerdp 2.11.2 (2.11.2), Running with libfreerdp 2.11.2 (rev 2.11.2), H.264 Yes
RDPF File RDP - RDP File Handler RDP plugin: 1.4.35 (Git 2a455ea), Compiled with libfreerdp 2.11.2 (2.11.2), Running with libfreerdp 2.11.2 (rev 2.11.2), H.264 Yes
RDPS Preference RDP - Preferences RDP plugin: 1.4.35 (Git 2a455ea), Compiled with libfreerdp 2.11.2 (2.11.2), Running with libfreerdp 2.11.2 (rev 2.11.2), H.264 Yes
SPICE Protocol SPICE - Simple Protocol for Independent Computing Environments 1.4.35
VNC Protocol Remmina VNC Plugin 1.4.35
VNCI Protocol Remmina VNC listener Plugin 1.4.35
WWW Protocol Remmina web-browser plugin 0.1.0
glibsecret Secret Secured password storage in the GNOME keyring 1.4.35
Build configuration: HAVE_ARPA_INET_H=1 HAVE_ERRNO_H=1 HAVE_FCNTL_H=1 HAVE_NETDB_H=1 HAVE_NETINET_IN_H=1 HAVE_NETINET_TCP_H=1 HAVE_SYS_SOCKET_H=1 HAVE_SYS_UN_H=1 HAVE_TERMIOS_H=1 HAVE_UNISTD_H=1 WITH_AVAHI=ON WITH_CLEANUP=OFF WITH_CUPS=ON WITH_FREERDP3=OFF WITH_GCRYPT=ON WITH_GVNC=ON WITH_ICON_CACHE=ON WITH_IPP=OFF WITH_LIBRARY_VERSIONING=ON WITH_MANPAGES=OFF WITH_NEWS=ON WITH_PYTHONLIBS=ON WITH_SSE2=ON WITH_STATS=ON WITH_TIP=ON WITH_TRANSLATIONS=ON WITH_UPDATE_DESKTOP_DB=ON
Build type: Release
CFLAGS: -O2 -pipe -g -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions -fstack-protector-strong -grecord-gcc-switches -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection -fno-omit-frame-pointer -fPIC -Wall -Wno-unused-result -Wno-unused-but-set-variable -Wno-deprecated-declarations -Wimplicit-function-declaration -Wredundant-decls
Compiler: GNU, 13.2.0
Target architecture: x64
sudo lshw -C video
*-display
description: VGA compatible controller
product: Ellesmere [Radeon RX 470/480/570/570X/580/580X/590]
vendor: Advanced Micro Devices, Inc. [AMD/ATI]
physical id: 0
bus info: pci@0000:05:00.0
logical name: /dev/fb0
version: e7
width: 64 bits
clock: 33MHz
capabilities: pm pciexpress msi vga_controller bus_master cap_list rom fb
configuration: depth=32 driver=amdgpu latency=0 resolution=1920,1080
resources: irq:28 memory:d0000000-dfffffff memory:cfe00000-cfffffff ioport:e000(size=256) memory:fbf80000-fbfbffff memory:c0000-dffff
uname -a
Linux clientpc 6.5.0-27-generic #28~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Fri Mar 15 10:51:06 UTC 2 x86_64 x86_64 x86_64 GNU/Linux
Contributions
In return, or to fix this issue, I'd be willing to:
-
Fix this myself. -
Donate ___ and/or have donated ___ towards fixing it. -
Take a donation of ___ to fix it. -
Update the documentation. -
Update the wiki. -
Translate Remmina in my native language(s) (___) on Hosted Weblate.