APAR status
Closed as program error.
Error description
Using IBM MQ 9.1, a channel remains stuck in an initializing/retrying state. The messages on the transmit queue increase as they are not able to be sent to the destination queue manager. Sometimes, "AMQ9514: Channel in Use" is reported for the channel in the queue manager error log, even though the channel is not running
Local fix
Sometimes, recycling of the qmgr works.
Problem summary
**************************************************************** USERS AFFECTED: This issue has been occasionally seen on MQ 9.1 sender/receiver channels, including cluster channels. Platforms affected: MultiPlatform **************************************************************** PROBLEM DESCRIPTION: A small timing window meant that an internal status record might not be correctly updated during the termination of a channel thread. This then caused the queue manager to incorrectly determine the old channel instance was still running when a new instance of the channel attempted to start.
Problem conclusion
Code to scan the channel status table is altered so that the status reflects properly when a channel goes out of scope. This additional check incurs a slight performance hit and so due to the very small number of observations of this issue in customer deployments, an environment variable must be set to enable these additional status checks: AMQ_CHL_PIDTID_CHECK=1 Design changes to the channel status logic in newer version of MQ mean that they are not susceptible to this timing window. --------------------------------------------------------------- The fix is targeted for delivery in the following PTFs: Version Maintenance Level v9.1 LTS 9.1.0.20 The latest available maintenance can be obtained from 'IBM MQ Recommended Fixes' https://www.ibm.com/support/pages/recommended-fixes-ibm-mq If the maintenance level is not yet available information on its planned availability can be found in 'IBM MQ Planned Maintenance Release Dates' https://ibm.biz/mqplannedmaintenance ---------------------------------------------------------------
Temporary fix
Comments
APAR Information
APAR number
IT42126
Reported component name
IBM MQ BASE MP
Reported component ID
5724H7271
Reported release
910
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2022-09-22
Closed date
2024-01-02
Last modified date
2024-01-02
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 BASE MP
Fixed component ID
5724H7271
Applicable component levels
[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSYHRD","label":"IBM MQ"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"910","Line of Business":{"code":"LOB67","label":"IT Automation \u0026 App Modernization"}}]
Document Information
Modified date:
14 March 2024