Can not get vncserver to start on rhel 7

Question

Good day

I'm running RHEL 7.6 with kernel version 3.10.0-514.el7.x86_64.

Vncserver version is tigervnc-server-1.8.0-17.el7.x86_64.

My vncserver@:1.service file looks like this, I have replaced <user> whith a valid user.

[Unit]
Description=Remote desktop service (VNC)
After=syslog.target network.target

[Service]
Type=forking
# Clean any existing files in /tmp/.X11-unix environment
ExecStartPre=/bin/sh -c '/usr/bin/vncserver -kill %i > /dev/null 2>&1 || :'
ExecStart=/sbin/runuser -l <user> -c "/usr/bin/vncserver %i"
PIDFile=/home/<user>/.vnc/%H%i.pid
ExecStop=/bin/sh -c '/usr/bin/vncserver -kill %i > /dev/null 2>&1 || :'

[Install]
WantedBy=multi-user.target

When I execute the command systemctl start vncserver@:1 I get the followin error

Job for vncserver@:1.service failed because a configured resource limit was exceeded. See "systemctl status vncserver@:1.service" and "journalctl -xe" for details.

systemctl status vncserver@:1 shows this

Oct 01 09:05:21 systemd[1]: Starting Remote desktop service (VNC)...

Oct 01 09:05:24 host_name systemd[1]: Can't open PID file /home/user/.vnc/host_name:1.pid (yet?) after start: No such file or directory

Oct 01 09:05:24 host_name systemd[1]: Failed to start Remote desktop service (VNC).

Oct 01 09:05:24 host_name systemd[1]: Unit vncserver@:1.service entered > failed state.

Oct 01 09:05:24 host_name systemd[1]: vncserver@:1.service failed.

Every time I execute systemctl start vncserver@:1 the N increase host_name:N.pid file in /home/user/.vnc it should stay at 1.

My xstartup file in the .vnc directory looks like this.

    #!/bin/sh
     unset SESSION_MANAGER 
     unset DBUS_SESSION_BUS_ADDRESS
     /etc/X11/xinit/xinitrc 
    # Assume either Gnome or KDE will be started by default when installed 
    # We want to kill the session automatically in this case when user logs out. In case you modify 
    # /etc/X11/xinit/Xclients or ~/.Xclients yourself to achieve a different result, then you should 
    # be responsible to modify below code to avoid that your session will be automatically killed 

     if [ -e /usr/bin/gnome-session -o -e /usr/bin/startkde ]; 
     then
         vncserver -kill $DISPLAY 
     fi

I have disabled my firewall and put seLinux in Permissive mode still the same error, however I have created a vncserver@:13.service file for root wich starts with no problem.

Any help will be greatly appreciated

Regards

Answer 1

I had the same issue on a centos-release-7-7.1908.0.el7.centos.x86_64 with 3.10.0-1062.4.3.el7.x86_64 kernel, exact same setup and configuration.

I noticed via journalctl -xe an error generated during startup phase of the service while trying to access the /tmp/.X11-unix/X59 file (my VNC is setup to run on port 5959). After manually deleting it, the service got regularly back on track.

Answer 2

RHEL7 and CentOS 7 come with iptables turned on by default. I received all sorts of odd errors from it. This was very similar to one of them You can make sure that this is your situation by running:

sudo systemctl status firewalld

If this is the case you should open VNC in your iptables, see details here: https://wiki.centos.org/HowTos/VNC-Server#Amend_the_iptables or https://www.cyberciti.biz/faq/linux-iptables-open-vncserver-port-6000-5800-5900/

Alternately if this server does not need to be secured by iptables (Ideally if it's behind a different firewall), you can just disable and stop iptables like so:

sudo systemctl stop firewalld && sudo systemctl disable firewalld

Stop will stop it and disable will stop it from returning after a restart.