APAR status
Closed as program error.
Error description
Attempts by an application to connect to a queue manager using a server connection SVRCONN channel with SHARECNV > 1 specified, unexpectedly receives MQRC 2538 MQRC_HOST_NOT_AVAILABLE. . Application has several threads with working connections to the queue manager. Client connections in the application work fine for some time, then start to fail.
Local fix
Set SHARECNV(1) on the SVRCONN channel definition
Problem summary
**************************************************************** USERS AFFECTED: All MQ client application users who use SVRCONN channels with SHARECNV value greater than 1. Platforms affected: MultiPlatform **************************************************************** PROBLEM DESCRIPTION: When shared conversation(SHARECNV) is set to any value greater than 1 then it means multiple logical connections (conversations) use the same channel instance. The channel instance is closed if all the conversations sharing the channel are disconnected. A small timing window allowed a new conversation to pick the same channel instance that was being ended by another thread and this results in the MQRC_HOST_NOT_AVAILABLE error.
Problem conclusion
The code has been modified to ensure that a new conversation request does not pick a channel instance that is being terminated. --------------------------------------------------------------- The fix is targeted for delivery in the following PTFs: Version Maintenance Level v9.0 LTS 9.0.0.8 v9.0 CD 9.1.0.0 The latest available 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
IT28091
Reported component name
IBM MQ BASE M/P
Reported component ID
5724H7261
Reported release
900
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2019-02-13
Closed date
2019-08-19
Last modified date
2020-03-16
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 M/P
Fixed component ID
5724H7261
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":"9.0","Edition":"","Line of Business":{"code":"LOB45","label":"Automation"}}]
Document Information
Modified date:
16 March 2020