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Use

The global listener and the X servers are the communication servers of the SAP MaxDB database system. They are located on the database computer. Applications (via interfaces) and tools need them to connect to databases that are located on remote database computers.

Note

The JDBC interface requires an X server even for local communication. Therefore all tools and applications that use the JDBC interface to connect to a database also need an X server for local communication, for example Database Studio.

There is one X server acting as a global listener on each database computer, and one X server for each SAP MaxDB installation. This means that on each database computer, there are at least one global listener and one X server.

Note

For the communication between older clients and databases as of version 7.8 as well as for communication between clients as of version 7.8 and older databases, the global listener acts as X server (downward-compatibility). Only for communication between clients and databases that are both of version ≥ 7.8, the global listener additionally provides the port-mapping function as described below.

To connect to a remote database, you have the following options:

  • You specify the database name, the port number for the database and the database computer.

    You are then directly connected to the X server of the installation to which the database belongs, and this X server connects you to the database.

  • You only specify the database name and the database computer. Internally, the system executes the following steps:

    1. The global listener receives the connection request and sends back the port number of the database.

    2. You are then directly connected to the X server of the installation to which the database belongs, and this X server connects you to the database.

Scope

Default Port

Function of the X Server

Protocol

Protocol Identifier

All installations on the database computer

7210

Global listener

TCP/IP

remote://

7269

Global listener with SAP networtk protocol NI (for connections via SAPRouter, only available in SAP systems)

NI

(based on TCP/IP)

sapni://

7270

Global listener with SAP networtk protocol NI and SAP encryption library (for connections via SAPRouter, only available in SAP systems)

NISSL (based on SSL/TLS)

remotes://

sapnis://

First installation <installation_1> on the database computer

7200

X server for <installation_1>

TCP/IP

remote://

Second installation <installation_2> on the database computer

7203

X server for <installation_2>

TCP/IP

remote://

Separate Database Studio installation

7299

X server for the separate Database Studio installation, only used by the system to access the local user management database .UMDB

TCP/IP

remote://

Connections to the database via SAPRouter are always established via the global listener. These connections use the NI or the NISSL protocol with designated ports.

For more information, see Concepts of the Database System, Network Communication.

 

Process Name

(Microsoft Windows)

Service Name

(Microsoft Windows)

Process Name

(Unix/Linux)

Global listener

serv.exe

XServer

globallistener

Installation-specific X server at <port>

serv.exe

XServer-<port>

vserver

NI server (for connections with SAPRouter, in SAP systems only)

- (part of the global listener)

-

niserver

NISSL server (for SSL connections with SAPRouter, in SAP systems only)

- (part of the global listener)

-

nisslserver

Communication between clients on remote computers and the X server can be encrypted with SSL/TLS in SAP systems.

For more information, see Database Administration, Encryption.

More Information