Sculptor server programs (kfserver and kfservnt)¶
Contents
The kfserver | kfservnt program runs on a machine in a network that has been designated as a database server, and waits for client programs on other machines in the network to connect to it.
kfserver | kfservnt performs operations on Sculptor keyed files and on sequential files on behalf of the client, and sends the results back over the network. It can also run child tasks on the server on behalf of the client, and perform some other tasks, such as notifying the client of the date and time settings on the server machine.
Once a file has been opened on the server, Sculptor automatically deals with all operations on that file as client/server requests.
kfserver works over the Internet in exactly the same way as over a local office network, only more slowly. Applications intended to work over the Internet should minimise file access. Programs should set the batch_read flag ON for all files that they access over the Internet.
General web pages containing Sculptor data and accessible to all can be displayed on the Internet without kfserver, by using the Sculptor run time interpreter nph-srep, which interprets Sculptor HTML files and Sculptor report programs with HTML output. See Internet applications.
Platforms¶
Under UNIX the kfserver program runs in the background automatically. The kfsmonc program is provided for the purposes of monitoring and controlling connections.
Under Windows, two versions of the server program are available: the service version kfservnt and the non-service version kfserver. The kfsmonw program is provided for the purposes of monitoring and controlling connections.
kfserver runs in the foreground as a normal process. As a non-service program, it can only be started by a logged-on user, and that user must remain logged on while kfserver is running. kfserver can be used on non-server versions of Windows. These platforms are not recommended for serious use as servers but can be convenient platforms for testing purposes.
The kfservnt program is a version of kfserver that runs as a service on Windows Server platforms. It is strongly recommended that a platform supporting kfservnt is chosen for use with Windows. There are many advantages to using a service. It is more stable, it is difficult to stop unintentionally, and it is very easy to start when the system itself starts up.
Starting and stopping server programs¶
Under UNIX, kfserver can be started by using the shell script startkfs and stopped by the C program stopkfs. It can also be started and stopped by the server monitor program kfsmonc.
Under Windows, kfserver can be started from the command line and stopped from its own menu option, or it can be started and stopped from the server monitor program kfsmonw. kfsmonw can also create, start and stop the Sculptor service version, kfservnt.
Number of clients permitted¶
Sculptor supports multiple, concurrently connected clients up to the limit allowed in the Sculptor licence key. Multiple connections from the same client machine count as one for licensing purposes. When a client program exits or calls the logout_server() function, its connection is closed.
Server duplication¶
A network can have any number of server machines. A database can therefore be distributed across several machines, or duplicated on two or more machines. At present Sculptor does not handle duplication automatically, so this must be coded into an application if required. A typical scenario is to send all updates to both server machines, but to read from only one. If a machine crashes, the other takes over all requests.
RELATED TOPICS |