APAR status
Closed as program error.
Error description
The agent.properties file for a MFT agent contans an optional property "outputLogFiles" that controls how many agent event logs are generated. For example: outputLogFiles=5 This should mean 5 event logs, called: - output0.log - output1.log - output2.log - output3.log - output4.log are generated and roll over as needed. However, once an agent fills up the final log file, the event logs are not rotated. Instead, the current output0.log file is deleted and a new one created.
Local fix
Problem summary
**************************************************************** USERS AFFECTED: This issue affects users of IBM MQ Managed File Transfer. Platforms affected: MultiPlatform **************************************************************** PROBLEM DESCRIPTION: Every Managed File Transfer agent has its own event log, which it uses to store informational messages as well as details of any errors that the agent has encountered. The number of files used to hold the event log, as well as the size of each file, is controlled by the agent properties: - outputLogFiles - outputLogSize The current event log file is called output0.log file, and historical event log files are called output<number>.log, where <number> is a value greater than 0. Details of the two properties mentioned above can be found in the: The agent.properties file topic in the IBM MQ sections of IBM Knowledge Center. The URI for this topic in the IBM MQ V8, V9.0.x and V9.1.x sections of IBM Knowledge Center are shown below: IBM MQ V8.0 http://www-01.ibm.com/support/knowledgecenter/SSFKSJ_8.0.0/com.i bm.wmqfte.doc/properties.htm IBM MQ V9.0.x https://www.ibm.com/support/knowledgecenter/en/SSFKSJ_9.0.0/com. ibm.wmqfte.doc/properties.html IBM MQ V9.1.x https://www.ibm.com/support/knowledgecenter/en/SSFKSJ_9.1.0/com. ibm.mq.ref.con.doc/properties.htm When an agent started up, it began writing to the current event log (output0.log). When this file reached its maximum size, as specified by the agent property outputLogSize, the agent would attempt to rename the event log files using the following logic: - Get the name of the oldest historical log file. - Rename the second oldest log file so that it has the name of the oldest historical log file. - Rename the third oldest log file, so that it has the name of the second oldest log file. - And so on. - After all of the historical log files have been renamed, rename the current log file (output0.log) to be output1.log. The agent then started to write to the new output0.log file. However, if the maximum number of historical log files (as specified by the agent property outputLogFiles) had been reached, the agent did not delete the oldest historical log file before performing the rename operations. This meant that: - Once the maximum number of historical log files had been created, - And the current event log file had reached its maximum size the rename operations would fail, as the target files already existed. As a result, the historical log files were not rotated. For example, suppose that an agent has been configured with the following agent properties: outputLogFiles=2 outputLogSize=1 When the agent started up, it created a new output0.log file, and started writing to it. When the file reached 1MB in size, the agent: - Renamed the output0.log file to output1.log. - Created a new output0.log file. After running for a period of time, the new output0.log file reached 1MB. When this happened, the following behaviour occurred: - The agent attempted to rename the existing output0.log file to output1.log. However, this rename operation failed as the output1.log file already existed. - The agent then created a new output0.log file, overwriting the original one, and started writing to it. As a result, the information in the previous output0.log file was lost.
Problem conclusion
IBM MQ Managed File Transfer has been updated so that: - If the maximum number of historical log files have been created (as specified by the agent property outputLogFiles). - And the current event log has reached its maximum size (as defined by the agent property outputLogSize). then agents will delete the oldest historical log file before renaming the other log files. This ensures that the rename operations work as expected, and the event logs to be rotated correctly. --------------------------------------------------------------- The fix is targeted for delivery in the following PTFs: Version Maintenance Level v8.0 8.0.0.11 v9.0 LTS 9.0.0.6 v9.1 CD 9.1.1 v9.1 LTS 9.1.0.2 The latest available MQ maintenance can be obtained from 'WebSphere MQ Recommended Fixes' http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037 If the maintenance level is not yet available information on its planned availability can be found in 'WebSphere MQ Planned Maintenance Release Dates' http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309 ---------------------------------------------------------------
Temporary fix
Comments
APAR Information
APAR number
IT26372
Reported component name
IBM MQ MFT V8.0
Reported component ID
5724H7252
Reported release
800
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2018-09-20
Closed date
2018-10-02
Last modified date
2018-10-02
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
IBM MQ MFT V8.0
Fixed component ID
5724H7252
Applicable component levels
[{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSYHRD","label":"IBM MQ"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"8.0","Edition":"","Line of Business":{"code":"LOB45","label":"Automation"}}]
Document Information
Modified date:
02 October 2018