Logical Spool Servers

Definition

A logical server stands for one or more other logical and/or real SAP spool servers. Logical servers can be used in place of real SAP spool servers anywhere in the spool system. The logical server is a “placeholder“ for the spool server assigned to it, while a real server is an actual application server with a spool work process and can output print requests.

If, for example, a logical server is specified as the spool server for output in the device definition of an output device, you have the following options:

· The logical server is directly assigned to a real spool server.

Printing can be performed using this real spool server.

· The logical server is directly assigned to another logical spool server.

The system check in turn for the assignment of this second logical server.

A real spool server with which printing can be performed must be present somewhere in the series of assignments.

The following figure shows some possibilities for how an output device can be assigned to a spool server:

A: Output device assigned directly to the spool server

B: Two output devices that are assigned to the spool server using a logical server

B: Two output devices that are assigned to the spool server using two logical servers

Use

You have the following options for printer administration through the use of logical spool servers:

· Grouping devices (local and remote printers): You can group the SAP output devices, for example, defining logical servers for devices connected over a network and for local devices. Both logical servers could point to the same real SAP spool server. However, you can manipulate the devices separately for such purposes as switching devices to another spool server.

· Switching Spool Servers: If you assign output devices to a logical spool server, you can then switch the devices from one server to another quickly and easily.

For example, if a spool server is down for maintenance, you can switch all of its devices to another server simply by changing the Mapping field in the definition of the logical spool server. When the original server is active again, you can switch the devices just as easily back to it.

Switching spool servers can be performed automatically. To do this, an alternative server must be specified in the spool server definition.

· Balancing the Output Workload: You can distribute the output processing workload of a spool server between the server and its alternative server.

To do this, you must have specified an alternative server and selected the option Allow Load Balancing.

· Transporting the Print Landscape Between Systems: Unlike real servers, logical servers can have the same names in different SAP Systems. You can therefore define a uniform SAP print architecture using logical servers and then transport this to all of your systems.

An output landscape of this type – device definitions and server definitions – can be transported in its entirety to another SAP System. After transport, you only need to enter the real spool servers that exist in the respective systems.