Chapter 8. Remotely accessing the desktop as multiple users
You can remotely connect to the desktop on a RHEL server and open multiple sessions as different users at the same time.
Install the VNC server:
[root]# dnf install tigervnc-server
Install the VNC client:
[root]# dnf install tigervnc
8.1. The mapping of port and display numbers to users in VNC
With VNC, the client can connect to the desktop sessions of different users on the server. A display number and a TCP port number are attached to each server user that exports a VNC session. The client uses the port number to specify which server user it connects to.
If several clients connect using the same port number, they all open a VNC session to the same server user.
You must configure a mapping for each server user that exports a VNC session. For every such user, you must pick a unique port and display number.
The recommended mapping
Red Hat recommends that you start with port number 5902 and display number 2 for the first user, and increment the numbers by one for each additional server user.
Port number 5900 and display number 0 represent the server user that is currently logged into the graphical session. You cannot start a VNC server for the user who is already logged into the graphical session.
Table 8.1. Port and display number pairs
|Port number||Display number||Note|
The logged-in user
The first recommended VNC user
Red Hat recommends that you do not configure the
root user to export a VNC session. A
root VNC session is unsafe and certain elements of the session might not work as expected.
You must open the selected ports in your firewall configuration. Allowing the
vnc-server service in your firewall opens ports from 5900 to 5903. If you need to enable access to additional server users, you must open ports above 5903 by manually specifying the port numbers.
8.2. VNC server configuration files
Several configuration files affect the behavior of the VNC server. You can configure the user mapping and various global options.
You can configure general options of the VNC server in the
/etc/tigervnc/vncserver-config-defaults configuration file. The file uses the following format:
session=gnome alwaysshared securitytypes=vncauth,tlsvnc desktop=sandbox geometry=2000x1200
The priority of configuration files
The VNC server reads the following files for general options, in order from most important to least important:
This file replaces the default configuration and has a higher priority than the per-user configuration. It is intended for system administrators who want to enforce particular VNC options.
Individual users can override the default VNC configuration in this file.
This file stores the default VNC configuration.
You can configure the mapping between users and their associated port and display numbers in the
/etc/tigervnc/vncserver.users configuration file. The file uses the following format:
For a list of available configuration options, see the
8.3. Enabling multi-user VNC access on the server
This procedure configures a RHEL server so that multiple users can open VNC sessions on it at the same time.
If you previously configured VNC using
systemdunit files, remove any outdated VNC configuration:
[root]# rm /etc/systemd/system/vncserver@.service
Map users to display and port numbers.
/etc/tigervnc/vncserver.usersconfiguration file, add a line for each server user that will export a VNC session:
- Replace user-number with the port and display number mapped to the selected existing user.
- Replace user-name with the user name of the selected existing user.
Open TCP ports 5900 to 5903 in the firewall:
[root]# firewall-cmd --permanent --add-service=vnc-server
Reload the firewall rules:
[root]# firewall-cmd --reload
Add the following lines to the
This configuration has the following effects:
- The VNC server starts the GNOME session when a remote user logs in.
- Multiple users can connect to the VNC server at the same time.
As each server user that exports a VNC session, set the VNC password for the user:
Remote clients must enter this password when connecting to the desktop on the server.
If you previously configured VNC for the user, ensure that the configuration files have the correct SELinux context:
[regular-user]$ restorecon -RFv ~/.vnc
Enable and start the VNC server unit for the regular user:
[root]# systemctl enable --now vncserver@:user-number
If the server uses the proprietary Nvidia driver, disable Wayland:
WaylandEnable=Falseline in the
DefaultSession=gnome-xorg.desktopoption to the
[daemon]section of the configuration file.
- Reboot the server.
- Uncomment the
8.4. Connecting to the VNC server as multiple users
This procedure connects to a remote desktop session using the
vncviewer application. You can open multiple connections to the remote desktop at the same time.
- Remote desktop access for multiple users is enabled on the server. For details, see Section 8.3, “Enabling multi-user VNC access on the server”.
Connect to the VNC server:
$ vncviewer --shared server-ip:display
- Replace server-ip with the IP address of the server that you are connecting to.
- Replace display with the display number where the server user exports the VNC session.