Ubuntu Manpage: vnc.conf - configuration file for Virtual Network Computing

Provided by: tigervnc-standalone-server_1.10.1+dfsg-3ubuntu0.20.04.1_amd64

NAME

       vnc.conf - configuration file for Virtual Network Computing

SYNOPSIS

       $variable = "someValue";

       $variable = "someValue";

       $variable .= "someValue";

       $variable = $var1 . $var2;

DESCRIPTION

       /etc/vnc.conf is the site wide configuration file for tigervncserver(1), the free X server
       for Virtual Network Computing (VNC). It can be used to change the behavior of  the  server
       at startup time, although for all values suitable defaults are preset.

       vnc.conf  will  be  parsed  by  tigervncserver.  Then tigervncserver will proceed and read
       $HOME/.vnc/vnc.conf, a file that can be changed on a per-user base. It has the some syntax
       and options as the file described in this document.

EXAMPLES

       The  site  wide  configuration  file  /etc/vnc.conf  should  come  with the Debian package
       tigervnc-standalone-server.   This  file  serves  as  an  example  for   the   user   file
       $HOME/.vnc/vnc.conf.   The  site  wide  configuration file is pretty self-descriptive, and
       this document will mainly repeat the information that already can be found there.

OVERVIEW

       The file is in perl(1) syntax, although only  variable  assignment  is  allowed  for  your
       safety  and  convenience.  But  there  still  a variety of possibilities to set the string
       variables.

       All variable names are prefixed by `$'. You can assign a string to a  variable  using  the
       `='  operator,  and you can append a string to a variable using the `.=' operator. You can
       concatenate two strings using the `.'  operator. You can substitute variables even  inside
       quotes. You can access the environment variables using the notation $ENV{VARIABLE}.

       You  can  unset  a  variable by assigning undef to it. Use this to return the state of the
       variable from `set' to `use default'.

       You must end a line with a semicolon.

OPTIONS

The options are given with their default value if this is known.

$vncClasses = "/var/www/vnc";
Should be the path to the java classes of the server.

$baseHttpPort = undef;
This is the port base for the mini-HTTP server that is built-in to Xtigervnc(1).
The real http port will be derived from this base plus the display number.

$XFConfigPath = "/etc/X11/xorg.conf";
Can be set to the global xorg.conf file. This will be parsed to gain default values
for $fontPath. If you want to disable this feature, point it to an invalid file,
/invalid for example.

$fontPath
Should be a comma separated list of fonts to be added to the font path. If not
specified, and $XFConfigPath is valid, tigervncserver will read the $fontPath from
there. If both are not set, the default will apply.

$PAMService = "tigervnc";
This parameter specifies the PAM service used for plain password authentication if
one of the security types Plain, TLSPlain, or X509Plain is used. If
/etc/pam.d/vnc is not present, then tigervncserver(1) expects to use the tigervnc
PAM service to authenticate the passwords of users when any of the *Plain security
types are used. Note that the tigervnc-common package provides the PAM service
configuration file /etc/pam.d/tigervnc. Otherwise, if /etc/pam.d/vnc is present,
then the vnc PAM service will be used.

$sslAutoGenCertCommand = "openssl req
-newkey ec:/etc/tigervnc/ecparams.pem
-x509 -days 2190 -nodes";
The command specified by the $sslAutoGenCertCommand parameter is used to auto
generate the certificate for the -X509Cert and -X509Key options of Xtigervnc(1).
The configuration for openssl(1SSL) is taken from /etc/tigervnc/ssleay.cnf where we
substitute @HostName@ by the fully qualified domain name of the host.

$vncUserDir = "$ENV{HOME}/.vnc";
Contains the filename for the log files directory of Xtigervnc (the server) and the
viewers that are connected to it.

$vncPasswdFile = $vncUserDir . "/passwd";
Contains the filename of the password file for Xtigervnc. This file is only used
for the security types VncAuth, TLSVnc, and X509Vnc.

$vncStartup = "/etc/X11/XSession";
Points to a script that will be started at the very beginning of the Xtigervnc
session.

$xauthorityFile = "$ENV{HOME}/.Xauthority";
Specifies the path to the X authority file that should be used by your Xtigervnc
server.

$desktopName = "${HOSTFQDN}:nn ($ENV{LOGNAME})";
Should be set to the default name of the desktop. This can be changed at the
command line with -name.

$wmDecoration = "8x64";
Sets the adjustment of $geometry to accommodate the window decoration used by the
X11 window manager. This is used to fully display the VNC desktop even if the VNC
viewer is not in full screen mode.

$geometry = "1900x1200";
This sets the framebuffer width & height. A default for this option as well as the
$depth and $pixelformat options can be derived if the tigervncserver(1) is run in a
X session – either $ENV{DISPLAY} or the session given by $getDefaultFrom – with the
-xdisplaydefaults option. The geometry can also be changed at the commandline with
the -geometry option. Otherwise, the fixed defaults given here as well as in the
following two configuration parameter documentations will be used.

$depth = "32";
This sets the framebuffer color depth, i.e., the number of bits per pixel to use.
It must be either 32, 24, 16, or 8.

$pixelformat = "rgb888";
Specifies the pixel format for the Xtigervnc(1) server to use (BGRnnn or RGBnnn).
The default for depth 8 is BGR233 (meaning the most significant two bits represent
blue, the next three green, and the least significant three represent red), the
default for depth 16 is RGB565 and for depth 24 and 32 is RGB888.

$getDefaultFrom
This option lets you set the display from which you can query the default of the
above three options, if you don't want to start tigervncserver from within a
running X server. It will be added to the call of xdpyinfo. It is useful to get
the default from the X server you will run xvncviewer in, because the data has not
to be recalculated then.

$getDefaultFrom = "-display localhost:0"; is an example how to do this.

$rfbwait = "30000";
Sets the maximum time in msec to wait for the VNC client viewer.

$localhost = "yes";
Should the TigerVNC server only listen on localhost for incoming TigerVNC
connections. This is useful if you use SSH and want to stop non-SSH connections
from any other hosts. Hence, $localhost = "yes" is the default if security types
are not specified. In this case, only the security type VncAuth will be offered.
If the security types are specified, either via the option -SecurityTypes given to
tigervncserver(1) or via the $SecurityTypes configuration parameter in
/etc/vnc.conf or in $HOME/.vnc/vnc.conf, then the default depends on the specified
security types. The default will be $localhost = "no" if the specified security
types contain at least one of the TLS* or X509* secutity types and also contain
none of the *None security types. As always, the defaults can be overwritten on
the commandline via the -localhost option or via the $localhost configuration
parameter in /etc/vnc.conf or in $HOME/.vnc/vnc.conf.

$SecurityTypes = "VncAuth"
The $SecurityTypes parameter contains a comma separated list of the default
security types the Xtigervnc server will offer. Available security types are None,
VncAuth, Plain, TLSNone, TLSVnc, TLSPlain, X509None, X509Vnc and X509Plain. The
*None security types do not offer any kind of user authentication for connecting
VNC sessions. Hence, combining a *None security type and $localhost = "no" is a
very bad idea. The TLS* and X509* security types do enforce SSL encryption for
data transmission. Hence, combining a TLS* or X509* security type and
$localhost = "yes" is a senseless idea. Thus, in the case of $localhost = "no",
the default for $SecurityTypes will be extended from VncAuth to VncAuth,TLSVnc.

$PlainUsers = "$ENV{LOGNAME}"
The $PlainUsers configuration parameter contains a comma separated list of users
that are authorized to access the VNC server if the security types Plain, TLSPlain,
or X509Plain are used to establish the connection. The password for these users are
check by the system via the PAM service specified via $PAMService option. On
default, only the user starting the tigervncserver is contained in the list. By
specifying *, any user can authenticate using this security type.

$X509Cert and $X509Key
These two options contain the filenames for a certificate and its key that is used
for the security types X509None, X509Vnc, and X509Plain. If nothing is specified –
the default case – then a self-signed certificate is auto-generated by
tigervncserver(1) and stored in $HOME/.vnc/${HOSTFQDN}-SrvCert.pem and
$HOME/.vnc/${HOSTFQDN}-SrvKey.pem, respectively. If filenames are given for
$X509Cert and $X509Key either here or on the commandline via -X509Cert and -X509Key
options, then the auto generation is disabled and the user has to take care that
usable certificates are present.

FILES

       /usr/bin/tigervncserver
              A wrapper script around Xtigervnc to start the server with appropriate defaults.

       /usr/bin/tigervncpasswd
              Command  to create and change password files to be used by the RFB protocol (can be
              specified in the $vncPasswdFile variable).   /usr/bin/Xtigervnc  The  real  server.
              Will be invoked by tigervncserver.

AUTHOR

       2016 - Modified for TigerVNC 1.7 by Joachim Falk (Joachim.falk@gmx.de) 2006 - Modified for
       vnc  4.1.2  by  Joachim  Falk  (Joachim.falk@gmx.de)  1998  - Originally written by Marcus
       Brinkmann (Marcus.Brinkmann@ruhr-uni-bochum.de) for the Debian GNU/Linux Distribution.