OpenEdge Data Management: DataServer for Microsoft SQL Server

Chapter 6: Connecting the DataServer
Setting the log file location
You can specify the absolute path of the log file name with –dslog startup switch to set
the location of the log file. The absolute path is obtained from the $DSLOGDIR
environment variable. So for example, setting $DSLOGDIR="C:\OE\Wrk\logs" and
setting -dslog to mydatasrv.lg, yields the target server log file name of
C:\OE\Wrk\logs\mydatasrv.lg. If $DSLOGDIR is not set and just the log file name is
specified, then the log file is created in the directory where the OpenEdge session
(client or agent) is started.
The path for the log file name is derived in the following order of preference.
1. Usage precedence is for –dslog with an absolute path name.
2. On specifying –dslog with relative path then path name, the –dslog specified is
relative to the $DSLOGDIR path.
3. If –dslog is a relative path and no value has been specified for $DSLOGDIR, then
the log file will located in the working directory where the DataServer server
component is started. This can be:
a. The current directory where the OpenEdge client is started, if using an
OpenEdge client with a self-service DataServer.
b. The working directory of your AppServer broker instance when using a
self-service DataServer in the Unified Broker framework.
c. The working directory of your DataServer broker instance when using a
client-server DataServer in the Unified Broker framework.
d. The current directory where you started your traditional broker using a
client-server DataServer with ProBroker.
If neither –dslog nor $DSLOGDIR are specified, the default log file name dataserv.lg
is used with the same directory path order of precedence as previously mentioned.
Handling log file creation errors
If creation of the DataServer log file fails for any reason, an error is reported and the
DataServer continues to execute. If an error occurs, the DataServer will derive its log
file name as ds_.lg where pid is the process id of the server process. The
DataServer continues to write log messages to ds_.lg log file. For example, if
you don’t have write privilege on the $DSLOGDIR directory, the ds_.lg file is
created in the directory where the client or broker agent is started. This behavior is
optionally available by default by setting environment variable $UNIQUE_DSLOG at
startup.
Restrictions on dynamic changes to log file
When the client and server share the same log file in self-service mode, the
LOG-MANAGER system handle is available to allow the log file to be managed. However,
when self-service DataServers don’t share the same log file with the client, or if the
DataServer is run in client-server mode, the server log file is likely to exist among other
servers writing to the same log simultaneously. For this reason, dynamic changes to
the log file, such as renaming or closing the log file, are restricted for all server log file
contexts. The one exception is the CLEAR-LOG(_) function which is allowed only if no
other process than the one initiating the CLEAR-LOG(_) is writing to the log file
simultaneously.
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