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Relocating MCTB (7mode) log files to avoid OnCommand/DFM backup contention

[ Edited ]

On Windows platforms DFM backup may fail to complete because it cannot compress the active log file (typically mctb.log).  This file is opened frequently for logging, especially at the default DEBUG log level and when the polling interval is low, making the likelihood of collision with the DFM backup process high.   The easiest way to resolve this is to relocate the MCTB log file(s) to a directory outside of the DFM installation area.  This can be done by changing daemon appender File value in the log4j.properties file under the MCTB config directory (typically C:\Program Files\NetApp\DataFabric Manager\DFM\script-plugins\MetroCluster-TieBreaker\conf\log4j.properties).   For example:

log4j.appender.DAEMON.File=C:/MCTB/logs/mctb.log

There are other appenders for VALIDATE and TRACER logs, but these are not used during normal operation.  The VALIDATE log is only used when the validate command is issued by the user (and not when validation is done during normal start up).   The TRACER log would only be used if the log level were set to TRACE, which doesn't provide any useful information and should not be used.   However, the File attributes can be changed for these appenders as well, if desired.  For example:

log4j.appender.VALIDATE.File=C:/MCTB/logs/validate.log
log4j.appender.TRACER.File=C:/MCTB/logs/trace.log

The Windows Service launcher (Apache procrun) will produce logs on start up, but these logs are not written to after start up under normal operation, and shouldn't cause any problems with DFM backup.   The location of these logs is determined by a value in the Windows Registry.  The following PowerShell command can be used to change the location of these start up logs, if desired:

Set-ItemProperty -path 'HKLM:SOFTWARE\Wow6432Node\Apache Software Foundation\Procrun 2.0\MCTB\Parameters\Log' -Name Path -Value 'c:\MCTB\logs'

 Note that quotes are necessary due to the spaces in the key path.

 

Of course, you are free to set these value to any path; the path provided is for just an example.