APAR status
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Closed as program error.
Error description
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The Configuring monitor retry behavior for message-to-file transfers topic in the MQ V9.1 section of IBM Knowledge Center (which can be found at the following URI: https://www.ibm.com/support/knowledgecenter/SSFKSJ_9.1.0/com.ibm .mq.adm.doc/m2f_mon_retry.htm) contains the following information: "If a message-to-file transfer that is triggered by a resource monitor fails and leaves the message group that triggered the monitor on the queue, that transfer is resubmitted at subsequent poll intervals. The number of times that the transfer is resubmitted is limited by the monitorGroupRetryLimit property of the monitoring agent." However, this functionality does not work. If a message-to-file transfer fails, it is never resubmitted or retried.
Local fix
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Recreate the MFT resource monitor using the -c and -f flags to have the failed message-to-file transfers resubmitted. In cases where the user wishes that the resubmitted transfer be updated in the MFT transfer log, they must remove the failed log entry using the MQ Explorer beforehand.
Problem summary
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**************************************************************** USERS AFFECTED: This issue affects users of IBM MQ Managed File Transfer who have agents that perform message-to-file transfers. Platforms affected: MultiPlatform **************************************************************** PROBLEM DESCRIPTION: IBM MQ V9.1 Managed File Transfer changed the way in which message-to-file transfers worked. Rather than destructively getting the messages as in previous releases, the source agent would browse the messages on the source queue during the transfer, and only delete them if the managed transfer was successful. This was done to prevent messages from being lost in the situations where a managed transfer failed part-way through. As a result of this change, the resource monitor retry functionality no longer worked. This functionality assumed that messages would be removed from the source queue during the transfer, and would be rolled back in the event that the transfer failed. This would cause the backout count of the messages to be increased. The resource monitor would then use the backout count to determine if a message on the source queue needed to be included in a managed transfer. The logic it would use is shown below: - If there is already a transfer with the same ID as that of message ID, then: - Do not submit a new managed transfer request for the message. - Else: - If the value of the agent property monitorGroupRetryLimit is set to -1 then: - Submit a new managed transfer for the message. - Else: - Check the backout count of the message. - If the backout count is greater than 1 and less than the value of the agent property monitorGroupRetryLimit: - Submit a new managed transfer for the message. - Else: - Leave the message on the queue. - End if - End if - End if However, as the messages were now browsed by the source agent, the backout count would always be zero. This meant that the resource monitor would never attempt to retry a failed message-to-file transfer.
Problem conclusion
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To resolve this issue, MQ Managed File Transfer resource monitors have been updated to keep a count of how many times a message-to-file transfer has been attempted. Every time a message-to-file transfer is started, the monitor updates the counter. The resource monitor will then compare the value of the agent property monitorGroupRetryLimit with the value of the counter, rather than the backout count of the message, in order to determine if a failed message-to-file transfer needs to be resubmitted or not. --------------------------------------------------------------- The fix is targeted for delivery in the following PTFs: Version Maintenance Level v9.1 LTS 9.1.0.7 v9.2 CD 9.2.1 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
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APAR number
IT29334
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Reported component name
IBM MQ MFT V9.1
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Reported component ID
5724H7272
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Reported release
910
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Status
CLOSED PER
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PE
NoPE
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HIPER
NoHIPER
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Special Attention
NoSpecatt / Xsystem
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Submitted date
2019-06-04
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Closed date
2020-06-17
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Last modified date
2020-06-17
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APAR is sysrouted FROM one or more of the following:
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APAR is sysrouted TO one or more of the following:
Fix information
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Fixed component name
IBM MQ MFT V9.1
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Fixed component ID
5724H7272
Applicable component levels
[{"Business Unit":{"code":"BU053","label":"Cloud & Data Platform"},"Product":{"code":"SSYHRD","label":"IBM MQ"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"910","Line of Business":{"code":"LOB45","label":"Automation"}}]
Document Information
Modified date:
31 March 2021