This blog describes the most commonly looked log and trace files paths and their purpose. I felt it will be handy for Basis Engineers in administering and troubleshooting Java Stack based systems especially for beginners.

This Blog was created to provide comprehensive overview of Java log, trace files paths and their purpose. Howerver this blog cannot cover all potential items as part of AS Java troubleshooting related information. At glance, this blog covers instance, server node, startup framework, bootstrap and etc,. logs, trace files.


This is being my first blog appreciate if any suggestion to improve.


Instance log files

Contents... Information about the J2EE instance startup, including parameters such as the startup profile used, the system ID (SID), the instance name, and the startup command used.

Use to analyze...Problems with the startup of the entrie J2EE instance. For example, the central and dialog J2EE instances are running on different physical servers and the startup profile is stored on the central J2EE instance. If a J2EE dialog instance cannot access the startup profile on the central J2EE instance due to access restrictions, it would report the permission problem in this log.

Location The log files of may be located under the following folders depending on the type of the instance:               
•/usr/sap/<SID>/JC<XX>/work for Java Central instance
•/usr/sap/<SID>/J<XX>/work for Java Central or Dialog instance
•/usr/sap/<SID>/DVEBMGS<XX>/work - for ABAP/DoubleStack Central instance
•/usr/sap/<SID>/D<XX>/work - for ABAP/DoubleStack Dialog instance

Log files The following log files can be distinguished:

•Files starting with std_: Log files from the standard output of the processes. In this file you may find the output produced  by System.out
•Files starting with jvm_  :The file may contain JVM error messages.
•Files starting with dev_ : The file may contain information about the exit code of the processes.
•stderr2 : Redirect out/err before start of framework
•dev_jstart: Developer trace of the JStart controller

Processes and log files
SAPStart service

Content... JStart and all its child processes have different log, trace files and all these files are located in work directory of jave instance.

Use to analyze...Contains information about startup process. You can check these files in case of errors and undesired behavior during the startup process.

Location: The logs can be found in these locations:
•/usr/sap/<SID>/JC<XX>/work for Java Central instance
•/usr/sap/<SID>/J<XX>/work for Java Central or Dialog instance
•/usr/sap/<SID>/DVEBMGS<XX>/work - for ABAP/DoubleStack Central instance
•/usr/sap/<SID>/D<XX>/work - for ABAP/DoubleStack Dialog instance

Log files
sapstart.env: Environmental data
sapstart.log: Log messages from the startup process
sapstart.old: Backup log file from the previous startup
sapstartsrv.log: General logs

Startup framework

Location: The logs can be found in these locations:
•/usr/sap/<SID>/JC<XX>/work for Java Central instance (deprecated)
•/usr/sap/<SID>/J<XX>/work for Java Central or Dialog instance
•/usr/sap/<SID>/DVEBMGS<XX>/work - for ABAP/DoubleStack Central instance
•/usr/sap/<SID>/D<XX>/work - for ABAP/DoubleStack Dialog instance

Log files
dej_jstart: Log messages containing JStart flow information
dev_jstart.0, dev_jstart.1: Backup log files from the previous startups
dev_*: Log files containing information about the startup of different processes
Example: dev_server0 is log file containing startup flow information about the first server node.
dev_.0, dev_.1: Old startup flow log files for different processes

Bootstrap

Content...Information about files that are synchronized at startup., including the J2EE component JAR files containing the J2EE libraries, services, and applications, and the J2EE component property files. In addition to it, java startup and control framework crates separate log files for each J2EE dispatcher and J2EE server process.

Use to analyze... Problems with bootstrap functionality that results in conditions such as unsynchronized J2EE configuration modifications or outdated java libraries.

Location:  The logs can be found in the locations:
•/usr/sap/<SID>/JC<XX>/work for Java Central instance (deprecated)
•/usr/sap/<SID>/J<XX>/work for Java Central or Dialog instance
•/usr/sap/<SID>/DVEBMGS<XX>/work - for ABAP/DoubleStack Central instance
•/usr/sap/<SID>/D<XX>/work - for ABAP/DoubleStack Dialog instance

Log files
dev_bootstrap: Contains Startup Framework flow entries
dev_bootstrap.0, dev_bootstrap.1: Old files containing Startup Framework flow entries from previous starts
log_bootstrap.log*: Rotating log files of the bootstrap process
std_bootstrap.out: The files contain the redirected output of Java's System.out
std_bootstrap.ou0, std_bootstrap.ou1: Backup logs from previous executions of the bootstrap
jvm_bootstrap.out: The file contains the redirected output of the JVM
jvm_bootstrap.ou0, jvm_bootstrap.ou1: Backup logs from previous executions of the bootstrap

Server

Contents...Information about a particular J2EE server process startup and shutdown. This file contains a list of loaded J2EE of loaded J2EE managers (LogManager, PoolManager, etc.), services and applications. If problem occurs, this log contains a description and reason, the GC statistics, and a J2EE server process thread dump.

Use to analyze...Problems with the statup of a particular J2EE manager or service.

Location:  The logs of the Startup Framework and the System.out output can be found in the locations:
The logs of the Startup Framework and the System.out output can be found in these locations:
•/usr/sap/<SID>/JC<XX>/work for Java Central instance
•/usr/sap/<SID>/J<XX>/work for Java Central or Dialog instance
•/usr/sap/<SID>/DVEBMGS<XX>/work - for ABAP/DoubleStack Central instance
•/usr/sap/<SID>/D<XX>/work - for ABAP/DoubleStack Dialog instance

The logs of the server node are located here:

/usr/sap/<SID>/JC<XX>/j2ee/cluster/server<X>/log - for Java Central instance /usr/sap/<SID>/J<XX>/j2ee/cluster/server<X>/log for Java Central and Dialog instances
/usr/sap/<SID>/DVEBMGS<XX>/j2ee/cluster/server<X>/log – for DoubleStack Centralinstance
/usr/sap/<SID>/D<XX>/j2ee/cluster/server<X>/log - for DoubleStack Dialog instance

Log files
defaultTrace_.trc*: Traces from the server processes, intended for developer's (and debug) use.
server_.log*:  Located in log-server folder. Targeted to system administrators. The file contains entries for serious problems
dev_server.out*: Startup Framework flow logs from the server node startup
dev_server.0, dev_server*.1*: Old startup flow log files for different processes
std_server.out*: System.out output of the server processes
std_server.out0, std_server*.ou1*: Backup logs from previous executions of the server node
jvm_server.out*: The file contains the redirected output of the JVM
jvm_server.ou0, jvm_server*.ou1*: Backup logs from previous executions of the processes

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I hope this blog will be useful in your day-to-day Java Stack based systems troubleshooting. And certainly this document is not the complete for Java stack based systems but this will be only useful.