Chapter 12. 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. Prerequisites Install the VNC server: Install the VNC client: 12.1. 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 12.1. Port and display number pairs Port number Display number Note 5900 0 The logged-in user 5901 1 5902 2 The first recommended VNC user 5903 3 ... ... Important 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. Firewall rules 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. 12.2. VNC server configuration files Several configuration files affect the behavior of the VNC server. You can configure the user mapping and various global options. General 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: For example: The priority of configuration files The VNC server reads the following files for general options, in order from most important to least important: /etc/tigervnc/vncserver-config-mandatory 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. USDHOME/.vnc/config Individual users can override the default VNC configuration in this file. /etc/tigervnc/vncserver-config-defaults This file stores the default VNC configuration. User mapping 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 example: Additional resources For a list of available configuration options, see the Xvnc(1) man page on your system. 12.3. 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. Prerequisites If you previously configured VNC using systemd unit files, remove any outdated VNC configuration: Procedure Map users to display and port numbers. In the /etc/tigervnc/vncserver.users configuration 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. For example: Open TCP ports 5900 to 5903 in the firewall: Reload the firewall rules: Add the following lines to the /etc/tigervnc/vncserver-config-defaults configuration file: 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: Enable and start the VNC server unit for the regular user: If the server uses the proprietary Nvidia driver, disable Wayland: Uncomment the WaylandEnable=False line in the /etc/gdm/custom.conf configuration file. Add the DefaultSession=gnome-xorg.desktop option to the [daemon] section of the configuration file. Reboot the server. Additional resources To enable VNC access to more than two server users, open TCP ports above 5903. For details, see Controlling traffic with predefined services using the CLI or Controlling traffic with predefined services using the GUI . 12.4. 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. Prerequisites Remote desktop access for multiple users is enabled on the server. For details, see Enabling multi-user VNC access on the server . Procedure Connect to the VNC server: 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.

Commands:
dnf install tigervnc-server
dnf install tigervnc
option1 = value option2
session=gnome alwaysshared securitytypes=vncauth,tlsvnc desktop=sandbox geometry=2000x1200
: number = user
:2=test :3=vncuser
rm /etc/systemd/system/vncserver@.service
: user-number = user-name
:2=vncuser
firewall-cmd --permanent --add-service=vnc-server
firewall-cmd --reload
session=gnome alwaysshared
[regular-user]USD vncpasswd
[regular-user]USD restorecon -RFv ~/.vnc
systemctl enable --now vncserver@: user-number
vncviewer --shared server-ip : display