Setting Server Log File Size

Manually set the server log file size, and the number of rollover archive files to maintain in the serviceability.xml configuration file.


By default, the FixedWindowRollingPolicy is implemented. With this policy, server log files grow to 20MB before rolling over, and 12 archived file instances are retained (for a total of 13 files, named <hostname>-smp-server.log, <hostname>-smp-server_1.log, <hostname>-smp-server_2.log, and so forth). Upon reaching the maximum size, the log overwrites the oldest archived file, and a new log is created.

Since the log fills up quickly, establish a file size and rollover policy that meets your record-keeping and troubleshooting needs. For example, you might want to specify smaller files, or you might want to copy archive files to storage for later analysis before they are overwritten.

You must have sufficient file space to support your decision. To calculate log file system usage, use this formula:
(Max - Min + 2) * Size = System Usage
If you have sufficient file space, SAP recommends:
  • MinIndex = 1; MaxIndex = 9 (the maximum number of archive files)
  • MaxFileSize = 20MB (the maximum file size)
(9 - 1 + 2) * 20MB = 200MB


  1. From File Explorer, navigate to <SMP_HOME>\Server\configuration\ .
  2. Open serviceability.xml in an editor such as Microsoft WordPad.
  3. Set server log file values:
    1. In the serviceability.xml file, search for <appender name="LJS_LOG_FILE", to locate these sections:
      <rollingPolicy class="ch.qos.logback.core.rolling.FixedWindowRollingPolicy">
      <triggeringPolicy class="ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy">
    2. In the rolling policy section, set the number of archived file instances. For example, change the <MaxIndex>12</MaxIndex> value from 12 (the default) to 9 to create fewer archived files.
      <rollingPolicy class="ch.qos.logback.core.rolling.FixedWindowRollingPolicy">
    3. For triggering policy, set the server log file size. For example, change the <MaxFileSize>20MB</MaxFileSize> value from 20MB (the default) to 5MB to create smaller archive files:
      <triggeringPolicy class="ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy">
    4. Compare the server log system usage requirements:
      (12 - 1 + 2) * 20MB = 260MB
      (9 - 1 + 2) * 5MB = 50MB
  4. Save and close the file.
  5. Restart SAP Mobile Platform Server for the changes to take effect.
  6. Repeat steps 1 ‒ 5 for each node in a cluster. The serviceability.xml file is not propagated across cluster nodes, so you must modify it on every node.