Procedure documentationEnqueue in AS Java: Troubleshooting


If you think there may be problems with the enqueue server, you can test the individual layers. Then you can approach SAP support with a more precise problem description.


To identify and fix problems yourself, you should be familiar with the architecture of the enqueue server.

More information: Locking in AS Java: Architecture.

The layers that can be tested are shown in the figure below:

This graphic is explained in the accompanying text.

Locking in AS Java: Components Involved

More information about the architecture of SAP NetWeaver Application Server Java: Architecture Manual.


Test Whether Enqueue Server is Functional

Use the enqt program to test whether Enqueue Server is able to accept client connections and perform lock operations. The program can be found in the /usr/sap/<SID>/SCS<instance number>/exe directory.

Note Note

Refer to the program's command line help or more information about how to start it, as well as the different options that you can execute. Enter enqt -help on the command line to access it.

End of the note.

You can use the following OpCodes to test whether Enqueue Server is functional:




Returns the lock table's creation ID.


Reads the lock table statistics.

Caution Caution

Note that enqt is a powerful program, which could bring the Enqueue Service to a standstill. The other OpCodes should only be used by SAP for testing.

End of the caution.

If problems arise, use the dev_eq_<process_ID> trace file of the enqt program for further investigation. This file is located in the /usr/sap/<SID>/SCS<instance number>/exe directory.

If the Enqueue Server has not been started or cannot be reached, the following message appears when you execute the enqt program:

*** ERROR => EncNiConnect: unable to connect (NIECONN_REFUSED) [encomi.c 444]

AS Java Locking Manager - Interface ServerInternalLocking

As described in Locking in AS Java: Architecture, the Locking Manager implements the interface ServerInternalLocking. This may only be called from AS Java, and not from a JEE application.

You can access the Locking Manager in the following ways:

The options that you have for testing are described in Managing Locks.

Application Locking Service

This is the service for creating and releasing locks and is available to JEE applications.

You can access the Application Locking Service in the following ways: