Installing the GwebS standalone server

The GwebS standalone server eliminates the need for a World Wide Web server, because it contains a small web server itself. Except for this, Gweb works identically in both modes (Stand-alone and as a CGI program). However, as it is a separate server, it needs configuration on how it should operate, which port to listen on, and so on.

GwebS configuration

The configuration file for gwebs is called gwebs.XXX and resides in the /usr/gar/config/default directory on Unix platforms, and C:\gar\config\default on Windows NT. The XXX part, called the "mode ID", is by default "DEF", but different configuration files can be selected using a parameter to gwebs, where "gwebs -mi ibm" instructs GwebS to use a configuration file calles

An installation of Gweb will write a file called gwebs.def in the configuration directory, but this should serve as an example only. Please modify this file with a normal text editor to suit your needs.

When you have created the configuration file, Gweb can be launched with the following parameters:

   gwebs [-mi XXX] [-dbg|-trace N] [-lp N]
         [-nb [off]|-na nnn.nnn.nnn.nnn ... [-nat nnn.nnn.nnn.nnn]]
         [-q] [-pid PIDFILENAME] (Unix only)

Instead of gwebs the command could be gwebss, in which case the secure (SSL) version of the server is started. See the separate GwebS SSL documentation.

The -nb and -na nnn.nnn.nnn.nnn parameters instruct the Gweb server to report statistics and load balancing information to Gproxy. With -nb (default on), load balancing information will be broadcasted to all Gproxy systems on the current subnet. With -na, this information will be sent to Gproxy on the IP address(es) given as a parameter. Up to four IP addresses can be supplied, separated by a space. Please consult the Gproxy manual for details on load balancing Gweb servers.

The -nat nnn.nnn.nnn.nnn parameter defines the IP address to report for itself to Gproxy. This parameter is only needed when GwebS and Gproxy is located inside a router doing Network Address Translation (NAT), and supplies the IP address that should be visible to client systems on the outside.

The -trace N parameter defines a trace level for all sessions started via this server. The -dbg parameter is equivalent to -trace 9.

The -lp N parameter defines the TCP/IP port number or service name GwebS should listen on. The default port number is 80 for non-SSL connections and 443 for SSL connections; the service names are "http" and "https" respectively. If specified on the command line, the -lp parameter overrides any port setting in the GwebS configuration file (see below).

The two latter parameters are for the Unix version only: -q starts gwebs in Quiet mode (nothing is displayed on stdout), and -pid PIDFILENAME causes the parent pid of the process to be written in the file PIDFILENAME. This makes it easier to terminate the server, with for example the command "kill `cat PIDFILENAME`".

On Windows NT, a dialog box will appear (unless the program is run as a service) where some statistics are updated, and there is a button for terminating the server. On Unix, the program will make itself a background process. In both cases, you can shut down GwebS using the G&R products Gmanager and/or Gmonitor.

GwebS will write to a log file and (depending on configuration) an access log file. These files are stored in the servers directory, which is /usr/gar/servers/XXXX.gwb directory on Unix platforms, and C:\gar\servers\XXXX.gwb on Windows NT. The XXXX part corresponds to your node's DSA name, as configured in the dsa.cfg configuration files. If you do not have configured a DSA name, Gweb will use the word "gweb" instead.

GwebS configuration file directives

Below is a list of all configuration directives you can use in the GwebS configuration file. Any line not starting with an alphabetic character [A-Z, a-z] is considered a comment line.

Port port-number/service-name

This defines the TCP/IP port GwebS listens for connections on. Default value is the standard HTTP port, 80. You can also specify the service name, e.g. Port http or Port https. Note that some systems require you to run with supervisor priviledges if you want to use a port number below 1024.

Listen IP-address or host name

This defines the TCP/IP address GwebS listens for connections on. The default setting is that GwebS listens on all interfaces on the machine. You may want to use this directive in multi-homed environments in order to control which web server corresponds to different IP addresses. Either a dotted quad-type address or a DNS resolvable host name must be specified.

Host hostname

This is the host name to use for self-referencing URLs. In some circumstances, the server needs to send redirect instructions back to your browser, and this redirect must contain a complete URL.

Default value: http://ip-address[:port]. Some browsers use either the 1.1 version of the HTTP protocol, or use a beefed-up 1.0 protocol, and automatically sends the Host: xxx request header. If this is the case, Gweb will use this host name instead of the IP address.

Content-type MIME-type Extension

This directive defines the WWW content type for files which various file extensions. You may override the defaults, and extend the table, with your own settings. The default values are:

   Content-Type  text/xml                     xml
   Content-Type  text/plain                   txt
   Content-Type  text/plain                   text
   Content-Type  text/html                    htm
   Content-Type  text/html                    html
   Content-Type  image/gif                    gif
   Content-Type  image/png                    png
   Content-Type  image/jpeg                   jpg
   Content-Type  image/jpeg                   jpeg
   Content-Type  image/jpeg                   jpe
   Content-Type  video/mpeg                   mpg
   Content-Type  video/mpeg                   mpeg
   Content-Type  video/mpeg                   mpe
   Content-Type  video/avi                    avi
   Content-Type  video/x-ms-wmv               wmv
   Content-Type  text/vnd.wap.wml             wml
   Content-Type  image/vnd.wap.wbmp           wbmp
   Content-Type  application/x-glink          glink
   Content-Type  application/x-javascript     js
   Content-Type  application/x-java-jnlp-file jnlp
   Content-Type  text/x-server-parsed-html    ssi
   Content-Type  text/x-server-parsed-html    shtml

Any file with an extension not defined in a Content-Type statement will be tagged with the MIME type application/octet-stream.

There is a special Content Type to be used for designating CGI scripts.

Logging Off|Standard|Extended

This directive controls the generation of a Webserver-like log file. The format, Common Log Format (CLF), is exactly the same as used on all major web servers, which means that it can be used with standard Web server log analysis tools.

The CLF file is called access.XXX (where XXX is the server's mode id) and contains one separate line for each request. A line is composed of several tokens separated by spaces:

     host ident authuser date request status bytes

The Extended CLF (also called the NCSA combined format) has two more fields at the end:

     referer user-agent

If a token does not have a value then it is represented by a hyphen (-). The meanings and values of these tokens are as follows:

The fully-qualified domain name of the client, or it's IP number if the name is not available.
If IdentityCheck is enabled and the client machine runs identd, then this is the identity information reported by the client. For GwebS, this field is always empty.
If the request was for a password protected document, then this is the userid used in the request. For GwebS, this field is always empty.
The date and time of the request, in the following format:

date = [day/month/year:hour:minute:second zone]
day = 2*digit
month = 3*letter
year = 4*digit
hour = 2*digit
minute = 2*digit
second = 2*digit
zone = +' |-') 4*digit

The request line from the client, enclosed in double quotes (").
The three digit status code returned to the client.
The number of bytes in the object returned to the client, not including any headers.
referer (extended format only)
If you had followed a hyperlink from some HTML page to make this request, this field contains the URL of the page where the link was -- i.e. where you came from.
user-agent (extended format only)
The User-Agent identification of the browser that made the request.

Index Index-file-name

This directive contains the name of a default file that the web server should give you if you requested a directory. You can specify multiple entries here; for example:

   Index index.htm
   Index index.html

If you request a directory (like, then Gwebs will first look for a file called, then for, then -- if none of these exist -- send you an error message.

Alias Virtual-path Physical-Path

This section describes the mapping between a request for a virtual path (a URL) and of the following:

Mapping a request to a file

The Physical-part represents the replacement part of the Virtual path. Example:

   Alias / U:\www\docs\                (Windows NT)
   Alias / \\machine\share\docs\       (Windows NT)
   Alias / /share/www/docs/            (Unix)
   Alias /xxx   (external redirect)

Here, a request to anything starting with a slash is mapped to a local file according to the rule above. Since this is effectively a catch-all, you would probably want to define this directive as the last one. In the example above, a request for results in that the file in the table below is sent to the browser:


If the file does not exist, an error message (HTTP error code 404) will of course be returned.

The last format causes any request for something that starts with /xxx to result in a redirection to an external url,

Mapping a request to the Gweb subsystem

The Virtual-part represents the location in the name space where you want Gweb to be visible. You would probably want to have something like /cgi-bin/gweb here, since this is the default location for CGI programs. However, since GwebS in itself does not use the CGI technique, you can use any valid value here. The Physical-path is the key word gweb. Whenever GwebS receives a request that begins with /cgi-bin/gweb, control is transferred to the Gweb facelifter.

Mapping a request to the Gweb status screen

The Virtual-part represents the location in the name space where you want the status screen to be visible. You could for example use /server-status here. The Physical-path is the key word server-status. Whenever GwebS receives a request that begins with /server-status, control is transferred to the Gweb status screen.

Mapping a request to the Web8/TDS-Web subsystems

The Virtual-part represents the location in the name space where you want Web8 or TDS-Web to handle the request. The Physical-path is the keyword web8 or TDS-Web, then a space, followed by a string used as a session name.

If no session name is given, Gweb assumes a session name equal to "node.application" (see below).

The Virtual-part syntax is always


where the node and application is information that your DPS 8000 department must give you.

Whenever GwebS receives a request that begins with /node.application, control is transferred to the Web8 susbsystem handler.

Mapping a request to the CGI program handler

The Virtual-part represents the location in the name space from where you want to execute a CGI program.

The Physical-path is the key word cgi, then a space, followed by the full path to the CGI program itself (and any program parameters it might require). If the named program does not include a full path, GwebS assumes that the CGI program resides in the same directory as the one containing the gwebs executable.

Whenever GwebS receives a request starting with Virtual-part, it starts the program named in Physical-path (including any parameters), sets up the environment for the program as defined in the CGI standard, sets the standard input to the CGI program to the TCP/IP data stream from the browser, and sends the program's standard output to the browser.

Note that you can also define CGI programs by its extension. For example, if you define a special Content-type named

   Content-Type script/cgi .cgi .exe

all requested files with the given file name extensions are treated as CGI programs.

Password Virtual-path username:password Realm

The Virtual-part represents the location in the name space that you you want to protect with a password.

The username:password text is a username and password pair (delimited by a single colon) that protects the virtual-part in question.

The Realm text is the prompt displayed to the user if you browse to a located protected by this password mechanism.

Note that neither the username nor the password can contain spaces. There may be multiple password settings for the same Virtual-part, but only the first Realm prompt defined will be used.

Example gwebs.def configuration file

*** gwebs.def configuration file for web host ""


Port http

Logging extended

Alias /server-status    server-status
Alias /cgi-bin/gweb     gweb
Alias /cgi-bin/nph-push cgi    nph-push
Alias /ph14.gartest     web8   browser
Alias /glinkj 
Alias /                 ../../html/

Password /server-status username:password Administrator Credentials

Index index.htm

Performance tuning

There are some extra parameters that control the performance of GwebS. In normal situations you should not need to adjust any of these values, but in some circumstances you might need to define in a more explicit way how GwebS operates.

These parameters can be defined both in the gwebs.def configuration file and on the command line. Command line parameters override configuration file parameters.

CmdlineConfig fileDefaultDescription
-minidle MinIdleServers 4 This directive defines the minimum number of server tasks (threads) waiting for a connection. GwebS will automatically create new server tasks if there are too few idle ones, in order to be prepared for new connections.
-maxidle MaxIdleServers 10 This directive defines the maximum number of server tasks (threads) waiting for a connection. GwebS will automatically terminate some server tasks if there are too many idle ones.
-minrun MinRunningServers 4 This directive defines the absolute minimum number of server tasks (threads). GwebS will never run with fewer tasks than this.
-maxrun MaxRunningServers 200 This directive defines the absolute maximum number of server tasks (threads). GwebS will never use more tasks than this.
-maxreq MaxRequestsPerChild 0 This directive defines the maximum number of browser requests a given server task can handle. The default of zero means that the server task is allowed to operate as many requests as needed. If you define a number her, the server task will automatically terminate. As an affect, GwebS will probably create a new task, depending on the parameters above.

Use the server-status mechanism described above to see details about the GwebS server tasks.