Servertec | Servlets

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iServer Servlets include Administrator, File, CGI, SSI, Servlet Include Tag, Servlet Invoker, Status, Cluster Redirector and Cluster Proxy.
Servlet | Description
AdminServlet | Implements iServer Administrator. Normally defined as a Servlet aliased as /admin.html.
CgiServlet | This Servlet implements Common Gateway Interface (CGI).
bindir | The base directory which contains CGI scripts. Normally ./cgi-bin.
exec | The shell to use. Normally c:\\command.com /c for WIN32 and /bin/sh for UNIX.
Normally defined as a Servlet aliased as /cgi-bin. Before CGI can be used Shell Access must be enabled in the iServer Administration - Server form.
ClusterProxy | The Cluster Proxy provides load balancing and fault tolerance by proxying client requests to an available workgroup of servers.
hosts | The comma delimited list of the names of the servers in the workgroup that requests will be proxy to. For example: p2,p3:8080
interval | Used to specify in milliseconds how often the workgroup servers status is updated. A value greater than or equal to 50 milliseconds. If an interval is not specified or if 0 is used then the workgroup server status is only checked if the method is best when the request is made. 1000 milliseconds is a good value to use. A value too small may have a negative impact on performance and a value too large when method is best may delay use of a recovered workgroup server.
method | The method used to determine which server within the workgroup will service the current request. best - the server with the best response time. next - the next available server. If a method is not specified then next is used.
retry | The number of workgroup servers to try to connect to, normally 3.
Normally defined as a Servlet aliased to the base URI to proxy.
ClusterRedirector | The Cluster Redirector provides load balancing and fault tolerance by redirecting client requests to an available workgroup of servers.
hosts | The comma delimited list of the names of the servers in the workgroup that requests will be redirected to. For example: p2,p3:8080
interval | Used to specify in milliseconds how often the workgroup servers status is updated. A value greater than or equal to 50 milliseconds. If an interval is not specified or if 0 is used then the workgroup server status is only checked if the method is best when the request is made. 1000 milliseconds is a good value to use. A value too small may have a negative impact on performance and a value too large when method is best may delay use of a recovered workgroup server.
method | The method used to determine which server within the workgroup will service the current request. best - the server with the best response time. next - the next available server. If a method is not specified then next is used.
retry | The number of workgroup servers to try to connect to, normally 3.
Normally defined as a Servlet aliased to the base URI to redirect.
FileServlet | This Servlet provides access to both files directories.
cache_size | The amount of memory in megabytes to use to cache files. 4 is the default for iServer. Must be 1 or more megabytes in size. Use 0 to disable the cache. A file cache may improve performance.
files | Comma delimited list of paths to files to preload into the cache. The size of file cache must be large enough to contain all of the files. Preloading commonly used files into the cache may improve performance.
System-wide parameters used by FileServlet are defined in iServer Administrator -> Manager -> Server
Default File | The name of the default html document to retrieve, if non was specified. index.html is the default for iServer.
Directory Access | Whether to allow directories to be displayed. No is the default for iServer. Setting this value to Yes is potentially a security hole. iServer uses /iws/html/directory.html, an html template, when displaying a directory.
Root Directory | The root directory for html files and documents. ./wwwroot is the default for iServer. ./public_html is also a popular value used by Web Servers. All references to files are made relative the base directory.
Normally defined as a Servlet aliased as /.
InvokerServlet | This Servlet allows iServer to run Servlets found in the CLASSPATH without the Servlet first having to be defined. Servlets can be run by entering: http://hostname:port/servlet/{package.}class{path}{?args}
hostname | The server running iServer. Normally localhost.
port | The port iServer is using. Normally 8080.
package | The Java Class package name.
class | The Java Class name.
path | Any path info.
args | Any parameters. Normally URL encoded key=value pairs.
Currently there is no way to pass initialization parameters to the Servlets invoked. If you need to pass initialization parameters you will need to directly define the Servet in servlets.ini or using the iServer Administrator. The CLASSPATH will be searched for the specified Servlet. Normally defined as a Servlet aliased as /servlet. #### Example http://localhost:8080/servlet/HelloServlet?World
ServletTagServlet | Provides support for Servlet includes using <servlet></servlet> tag in the form: <servlet name=servlet {code=class} {init_param_name=init_param_value}...> {<param name=param_name value=param_value>}... </servlet>
class | The name of a class file that can be found using the CLASSPATH. code is used to load the Servlet when name is not specified. When code is used the Servlet is loaded, initialized and destroyed each time it is used.
init_param_name | The name of an initialization parameter.
init_param_value | The value that will be associated with the named initialization parameter.
param_name | The name of a parameter.
param_value | The value that will be associated with the named parameter.
servlet | A Servlet Alias defined in iws_dir/config/servlets.ini, where iws_dir is the directory where iServer was installed. If name is not specified then the class defined in code will be used to load the Servlet. When name is used the Servlet is loaded and initialized only once and destroyed when the server is shutdown.
Normally defined as a Filter aliased as .ssi file extension. #### Example <servlet name=HelloServlet></servlet>
SSIncludeServlet | Provides support for SSI.
exec | The shell to use when executing #exec directive. Normally c:\\command.com /c for WIN32 and /bin/sh for UNIX.
Normally defined as a Filter aliased as .shtml file extensions. Before #exec directive can be used Shell Access must be enabled in the iServer Administration - Server form.
StatusServlet | Used by workgroup servers to provide the Cluster Redirector with load and availability status. Normally defined as a Servlet aliased as /status.
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