How to fix NoVNC Console Just Black Screen

Debian 5,6,7

This will also work in debian8 if you use sysv-init instead of systemd

Editing the config file via the host

You can do this on the host without entering CT (but the CT must be running). Just log in to the Proxmox VE host and:

edit all inittabs under /var/lib/vz/root/ :

 nano /var/lib/vz/root/*/etc/inittab

 # add this
 1:2345:respawn:/sbin/getty 38400 tty1

Editing the configuration file inside the container

Login via SSH (or use the VNC "Shell") to your PVE host and 'vzctl enter CTID' the container:

List all running container:

pve:~# vzlist
     CTID      NPROC STATUS    IP_ADDR         HOSTNAME
      108         23 running   192.168.9.20    ubuntu-1204.pve.com
      109         18 running   192.168.9.21    centos63-64.pve.com
      111         15 running   192.168.9.23    centos5-64.pve.com
      114         14 running   192.168.9.30    deb6-32.pve.com
      115         15 running   192.168.9.31    deb7-32.pve.com
      122         14 running   192.168.9.36    deb5.pve.com

Enter the container:

pve:~# vzctl enter 122

root@debian:/# nano /etc/inittab

On the bottom of /etc/inittab just add the following line:

1:2345:respawn:/sbin/getty 38400 tty1

Save the changes and shutdown/start the container via Console.

Ubuntu

Ubuntu 10.04, 12.04, 14.04

Login via SSH (or use the VNC "Shell") to your PVE host and 'vzctl enter CTID' the container:

List all running container:

pve:~# vzlist
     CTID      NPROC STATUS    IP_ADDR         HOSTNAME
      108         23 running   192.168.9.20    ubuntu-1404.pve.com
      109         18 running   192.168.9.21    centos63-64.pve.com
      111         15 running   192.168.9.23    centos5-64.pve.com
      114         14 running   192.168.9.30    deb6-32.pve.com
      115         15 running   192.168.9.31    deb7-32.pve.com
      122         14 running   192.168.9.36    deb5.pve.com

Enter the container:

prpmox-ve:~# vzctl enter 108

root@ubuntu-1404:/# nano /etc/init/tty1.conf

Change/Create the file that it looks exactly like this:

# tty1 - getty
#
# This service maintains a getty on tty1 from the point the system is
# started until it is shut down again.

start on stopped rc RUNLEVEL=[2345]

stop on runlevel [!2345]

respawn
exec /sbin/getty -8 38400 tty1

Save the changes and shutdown/start the container via Console.

Centos

Centos 5 / 7

Login via SSH (or use the VNC "Shell") to your PVE host and 'vzctl enter CTID' the container:

List all running container:

pve:~# vzlist
     CTID      NPROC STATUS    IP_ADDR         HOSTNAME
      108         23 running   192.168.9.20    ubuntu-1204.pve.com
      109         18 running   192.168.9.21    centos63-64.pve.com
      111         15 running   192.168.9.23    centos5-64.pve.com
      114         14 running   192.168.9.30    deb6-32.pve.com
      115         15 running   192.168.9.31    deb7-32.pve.com
      122         14 running   192.168.9.36    deb5.pve.com

Enter the container:

pve:~# vzctl enter 111

root@centos5-64:/# nano /etc/inittab

On the bottom of /etc/inittab just add the following line:

1:2345:respawn:/sbin/agetty tty1 38400 linux

Save the changes and shutdown/start the container via Console.

Centos 6

Login via SSH (or use the VNC "Shell") to your PVE host and 'vzctl enter CTID' the container:

List all running container:

pve:~# vzlist
     CTID      NPROC STATUS    IP_ADDR         HOSTNAME
      108         23 running   192.168.9.20    ubuntu-1204.pve.com
      109         18 running   192.168.9.21    centos63-64.pve.com
      111         15 running   192.168.9.23    centos5-64.pve.com
      114         14 running   192.168.9.30    deb6-32.pve.com
      115         15 running   192.168.9.31    deb7-32.pve.com
      122         14 running   192.168.9.36    deb5.pve.com

Enter the container:

pve:~# vzctl enter 109

root@centos63-64:/# nano /etc/init/tty.conf

Change/Create the file that it looks exactly like this:

# This service maintains a getty on tty1 from the point the system is
# started until it is shut down again.

start on stopped rc RUNLEVEL=[2345]

stop on runlevel [!2345]

respawn
exec /sbin/agetty -8 tty1 38400

Either run "start tty" without rebooting the container, or save the changes and shutdown/start the container via Console.

Troubleshooting

If you still want to use the previous method (vzctl enter CTID) you can open the host "Shell" and just type 'vzctl enter CTID" to manage your containers.

Java browser plugin

The console is using a Java applet, therefore you need latest Oracle (Sun) Java browser plugin installed and enabled in your browser (Google Chrome and Firefox preferred). If you are on Windows desktop, just go to java.com, if you run a Linux desktop you need to make sure that you run Oracle (Sun) Java plugin instead of the default openjdk. For Debian/Ubuntu based desktops, see Java_Console_(Ubuntu)

Modifying your templates

If you don't want to commit the changes above for every single CT you create, you can simply update the templates accordingly. For this, simply place the file you want to insert into your template (like etc/inittab for debian containers) into your template folder and update the template. The following is specific to CentOS 6, just replace filename/path and contents with the appropriate contents found above.

cd [TEMPLATE LOCATION] #Modify this

mkdir -p etc/init

cat <<EOF >etc/init/tty.conf
# This service maintains a getty on tty1 from the point the system is
# started until it is shut down again.

start on stopped rc RUNLEVEL=[2345]

stop on runlevel [!2345]

respawn
exec /sbin/agetty -8 tty1 38400
EOF

gunzip centos-6-standard_6.3-1_amd64.tar.gz
tar -rf centos-6-standard_6.3-1_amd64.tar etc
gzip centos-6-standard_6.3-1_amd64.tar

rm etc/init/tty.conf
rmdir -p etc/init

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