VNC over SSH

From Alteeve Wiki
Revision as of 16:20, 18 August 2022 by Digimer (talk | contribs)
Jump to navigation Jump to search

 Alteeve Wiki :: How To :: VNC over SSH

This tutorial covers setting up VNC over SSH on EL8.3+ (RHEL 8, CentOS Stream 8, etc). and EL9.

Template note icon.svg
Note: Make sure all admin users are logged out (Gnome and terminal). There is a bug we don't know the source of yet that can break the ability to log into gnome.

VNC Server Setup

SSH into the Striker dashboard as the root user.

dnf install tigervnc-server
Last metadata expiration check: 0:19:19 ago on Wed 17 Aug 2022 12:06:35 PM EDT.
Dependencies resolved.
 Package                             Architecture       Version                   Repository             Size
 tigervnc-server                     x86_64             1.12.0-5.el8              appstream             285 k
Installing dependencies:
 tigervnc-license                    noarch             1.12.0-5.el8              appstream              40 k
 tigervnc-selinux                    noarch             1.12.0-5.el8              appstream              48 k
 tigervnc-server-minimal             x86_64             1.12.0-5.el8              appstream             1.1 M

Transaction Summary
Install  4 Packages

Total download size: 1.5 M
Installed size: 3.4 M
Is this ok [y/N]: y
Downloading Packages:
(1/4): tigervnc-license-1.12.0-5.el8.noarch.rpm                               223 kB/s |  40 kB     00:00    
(2/4): tigervnc-selinux-1.12.0-5.el8.noarch.rpm                               216 kB/s |  48 kB     00:00    
(3/4): tigervnc-server-1.12.0-5.el8.x86_64.rpm                                982 kB/s | 285 kB     00:00    
(4/4): tigervnc-server-minimal-1.12.0-5.el8.x86_64.rpm                        4.9 MB/s | 1.1 MB     00:00    
Total                                                                         2.7 MB/s | 1.5 MB     00:00     
Running transaction check
Transaction check succeeded.
Running transaction test
Transaction test succeeded.
Running transaction
  Preparing        :                                                                                      1/1 
  Running scriptlet: tigervnc-selinux-1.12.0-5.el8.noarch                                                 1/4 
  Installing       : tigervnc-selinux-1.12.0-5.el8.noarch                                                 1/4 
  Running scriptlet: tigervnc-selinux-1.12.0-5.el8.noarch                                                 1/4 
  Installing       : tigervnc-license-1.12.0-5.el8.noarch                                                 2/4 
  Installing       : tigervnc-server-minimal-1.12.0-5.el8.x86_64                                          3/4 
  Installing       : tigervnc-server-1.12.0-5.el8.x86_64                                                  4/4 
  Running scriptlet: tigervnc-server-1.12.0-5.el8.x86_64                                                  4/4 
  Verifying        : tigervnc-license-1.12.0-5.el8.noarch                                                 1/4 
  Verifying        : tigervnc-selinux-1.12.0-5.el8.noarch                                                 2/4 
  Verifying        : tigervnc-server-1.12.0-5.el8.x86_64                                                  3/4 
  Verifying        : tigervnc-server-minimal-1.12.0-5.el8.x86_64                                          4/4 

  tigervnc-license-1.12.0-5.el8.noarch               tigervnc-selinux-1.12.0-5.el8.noarch                     
  tigervnc-server-1.12.0-5.el8.x86_64                tigervnc-server-minimal-1.12.0-5.el8.x86_64              


Edit /etc/tigervnc/vncserver.users to enable the admin access via VNC.

diff -u /root/vncserver.users /etc/tigervnc/vncserver.users
--- /root/vncserver.users	2022-08-17 13:59:09.924844674 -0400
+++ /etc/tigervnc/vncserver.users	2022-08-17 14:02:37.893980059 -0400
@@ -5,4 +5,4 @@
 # :2=andrew
 # :3=lisa

Now edit to enable defaults.

diff -u /root/vncserver-config-mandatory /etc/tigervnc/vncserver-config-mandatory
--- /root/vncserver-config-mandatory	2022-08-17 13:53:31.861747957 -0400
+++ /etc/tigervnc/vncserver-config-mandatory	2022-08-17 13:58:45.678479131 -0400
@@ -9,8 +9,8 @@
 # Several common settings are shown below. Uncomment and modify to your
 # liking.
-# session=gnome
-# securitytypes=vncauth,tlsvnc
-# geometry=2000x1200
-# localhost
-# alwaysshared
Variables Description
session Is set to a valid Xsession name as per configuration files in /usr/share/xsessions/
securitytypes Denotes the authentication options presented to clients
desktop Sets the name of the desktop session displayed by various components, including the vnc client
geometry Denotes the aspect ratio and native resolution of the session
localhost Denotes the host to which the server will bind
alwaysshared Sets all incoming connections as shared, regardless of client settings

Switch to the admin user.

su - admin
Last login: Wed Aug 17 12:13:44 EDT 2022 on tty2
[admin@an-striker01 ~]$

Now run vncpasswd and enter the password you will use to connect.

Would you like to enter a view-only password (y/n)? n
A view-only password is not used

Exit back to the root user.

[root@an-striker01 ~]#

Now enable the daemon;

systemctl enable --now vncserver@:2.service
Created symlink /etc/systemd/system/ → /usr/lib/systemd/system/vncserver@.service.


Now you can try to connect!

If connecting directly to the target

Open the tunnel;

ssh -L 5902:localhost:5902 -N -f -l $user $host_name

Then on the local machine, run tigervnc, then connect to localhost:2:

If connection via a gateway ssh machine

Connect to the gateway;

Then from the gateway, connect to the target;

Then on the local machine, run tigervnc, then connect to localhost:2:


Any questions, feedback, advice, complaints or meanderings are welcome.
Us: Alteeve's Niche! Support: Mailing List IRC: #clusterlabs on Libera Chat   © Alteeve's Niche! Inc. 1997-2022
legal stuff: All info is provided "As-Is". Do not use anything here unless you are willing and able to take responsibility for your own actions.