PK77424: AFTER STARTUP OF A Z/OS APPLICATION SERVER WITH MDBS CONSUMING FROM A DESTINATION, MESSAGES REMAIN LOCKED INDEFINITELY.

Fixes are available

APAR status

Closed as program error.

Error description

The WebSphere Application Server for z/OS Version 6.0.2
application server was started with messages on a service
integration bus queue. A message-driven bean (MDB) was
configured to consume from that queue.
The messaging engine was in the same server as the
message-driven bean. 10 messages remained permanently in
Locked status on the queue. This number corresponds with the
"Maximum concurrent endpoints" value defined on the activation
specification.

For each locked message the following error was logged once in
the job log of the servant region:
BBOO0221W: CWSIV1052W: The inbound resource adapter received
the exception javax.resource.ResourceException:
CWSIV0951E: An internal error occurred. The exception
com.ibm.websphere.sib.exception.SIResourceException:
CWSIC1001E: A client attempted to connect with a remote
messaging engine (tcp bridge service) but the connection
cannot be completed. Ensure the messaging engine is started:
exception
com.ibm.ws.sib.jfapchannel.JFapConnectFailedException:
CWSIJ0063E: A network connection to host name null
, port null cannot be established.. was thrown while
attempting to create a connection to messaging engine
<MEUUID>. when processing the message handle
com.ibm.wsspi.sib.core.SIMessageHandle;?302a803c from the
session 2 on messaging engine <MEUUID>.

Local fix

Problem summary

****************************************************************
* USERS AFFECTED:  Users of the default messaging provider     *
*                  for WebSphere Application Server for z/OS   *
*                  Version 6.0, Version 6.1 and Version 7.0    *
****************************************************************
* PROBLEM DESCRIPTION: On startup of an application server     *
*                      that is hosting both a messaging        *
*                      engine and a message-driven bean,       *
*                      messages might remain in Locked         *
*                      status.                                 *
*                                                              *
*                      For WebSphere Application Server        *
*                      Version 6.0, messages might be locked   *
*                      indefinitely. For WebSphere             *
*                      Application Server Version              *
*                      6.1 and Version 7, messages might be    *
*                      locked for up to 5 minutes.             *
****************************************************************
* RECOMMENDATION:                                              *
****************************************************************
When a z/OS application server that hosts both a
messaging engine and a message-driven bean starts, messages
that are available on a service integration bus queue are
in Locked status in the messaging engine that is running in the
control region adjunct. Then the locked messages are passed to
the z/OS Workload Management system to be dispatched to a
servant region.

However, these messages might be dispatched to a
servant region before the infrastructure that is required
to connect it to the messaging engine using a
cross-memory connection has been initialized. As a result,
CWSIV1052W messages are logged in the servant region.

Each message then remains in Locked status within the messaging
engine until the messaging engine reaches a timeout. At this
point each message is unlocked, immediately locked again, and
dispatched again to the z/OS Workload Management system.

In WebSphere Application Server Version 6.0 the timeout period
is indefinite. Consequently messages were never unlocked
within the messaging engine, and were never delivered to
applications unless the message-driven bean was stopped and
restarted.

In WebSphere Application Server Version 6.1 and later, the
timeout period was 5 minutes.

Problem conclusion

The fix for this APAR sets the default value for the
timeout to 5 minutes in WebSphere Application Server
Version for z/OS 6.0.

The fix also creates the following tuning property for
all versions of WebSphere Application Server for z/OS. This
property can be specified in the sib.properties file:
Name:         sib.ra.zosMessageLockTimeout
Valid values: Non-zero number of seconds
Default:      300
Setting this property allows the timeout to be reduced, to
allow messages to be redelivered in less than 5 minutes
after startup if this condition is encountered.

This APAR also fixes a deadlock between threads in the
following methods in WebSphere Application Server Version 6.0:
com.ibm.ws.sib.processor.impl.JSLocalConsumerPoint.
internalStop()
com.ibm.ws.sib.processor.impl.JSLocalConsumerPoint.put()
com.ibm.ws.sib.processor.impl.LockedMessageEnumerationImpl.
addNewMessage()
This secondary issue is not specific to the z/OS platform and
can only occur when the message lock timeout is non-zero.

The fix for this APAR is currently targeted for inclusion in
fixpack 6.0.2.35, 6.1.0.25 and 7.0.0.5.  Please refer to the
Recommended Updates page for delivery information:
http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980

Temporary fix

Comments

APAR Information

APAR number
PK77424
Reported component name
PLAT MSG COM
Reported component ID
620400101
Reported release
100
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2008-12-12
Closed date
2009-01-29
Last modified date
2009-01-29

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
PLAT MSG COM
Fixed component ID
620400101

Applicable component levels

R100 PSY
UP

[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSEQTP","label":"WebSphere Application Server"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"6.0","Line of Business":{"code":"LOB45","label":"Automation"}}]

Document Information

Modified date:
29 December 2021

Tips

PK77424: AFTER STARTUP OF A Z/OS APPLICATION SERVER WITH MDBS CONSUMING FROM A DESTINATION, MESSAGES REMAIN LOCKED INDEFINITELY.

Fixes are available

Subscribe

APAR status

Closed as program error.

Error description

Local fix

Problem summary

Problem conclusion

Temporary fix

Comments

APAR Information

APAR number

Reported component name

Reported component ID

Reported release

Status

PE

HIPER

Special Attention

Submitted date

Closed date

Last modified date

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

Fixed component ID

Applicable component levels

R100 PSY

Document Information

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