PM60436: MESSAGES ARE NOT DISTRIBUTED TO LOAD BALANCED SERVICE INTEGRATION BUS MESSAGE ENGINES

Fixes are available

APAR status

Closed as program error.

Error description

In a High Availability and High scalability messaging engine
topology, message distribution to neighboring message engines
(ME) failed due to either stale ME connection information or
missing ME connection information.

Presence of the following message from the ME trace would be
the match for this problem.

----------------------------------
Due to stale neighborhood ME connection information, message
was sent to the wrong ME

[11/3/11 14:50:36:773 IST] 0000002c MPIO          3
(com.ibm.ws.sib.processor.io.MPIO) [:] Ignoring message as in
stopped state

(or)

Due to missing neighborhood ME connection information, there is
no clue about the target ME. So source ME cannot send message
to the neighborhood(target) ME.

[1/23/12 15:07:34:713 IST] 00000036 MPIO < findMPConnection
(com.ibm.ws.sib.processor.io.MPIO) [bus1:cluster1.000-bus1] Exit
<null>
----------------------------------

For example, we have a messaging setup with a cluster which has
4 application servers as bus member. Messaging queue names
are:Q1, Q2, Q3, and Q4. When application sends 4000 messages
with load balancing, in a non working scenario the final
results of messages in each message-engine (queue) is: Q1-1000,
Q2-1000, Q3-1000, and Q4=0. This problem cannot be recreated
all the time. If we restart the ME for Q4 (or) the entire
cluster, the problem would go away.

This problem is specific to high availability (or) high
availability and high scalability setup.

Local fix

Problem summary

****************************************************************
* USERS AFFECTED:  Users of the default messaging provider     *
*                  for IBM WebSphere Application Server        *
*                  Versions 7.0, 8.0 and 8.5                   *
****************************************************************
* PROBLEM DESCRIPTION: Messages are not distributed properly   *
*                      to a load balanced Service Integration  *
*                      Bus(SIB) Messaging Engines(ME).         *
****************************************************************
* RECOMMENDATION:                                              *
****************************************************************
In a high scalability setup there is a possibility of an ME
transitioning from one server to another server during cluster
startup. ME transitioning means that ME is stopped in one
server and the same ME is started in the other server to
balance the number of MEs running on each application server.
During cluster startup, there is ME transition between
application servers because one application server might be
fully started while other application server is in the process
of starting.
This problem is specific to high availability or high
availability and high scalability setup. This problem cannot
be recreated all the time. The problem was due to neighborhood
ME information not get cleaned properly during ME stop (during
ME transition).

Problem conclusion

Modified the source code to add cleanup in ME stop and a fresh
initialization of neighbourhood ME information during ME
start.

The fix for this APAR is currently targeted for inclusion in
fix packs 7.0.0.27, 8.0.0.7, and 8.5.0.2. Please refer to the
Recommended Updates page for delivery information:
http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980

Temporary fix

Restart the message engine where the messages are not
distributed (or) restart the application server JVM (or) the
entire cluster.

Comments

APAR Information

APAR number
PM60436
Reported component name
WAS SIB & SIBWS
Reported component ID
620800101
Reported release
300
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2012-03-14
Closed date
2012-10-17
Last modified date
2012-10-17

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
WAS SIB & SIBWS
Fixed component ID
620800101

Applicable component levels

R800 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":"7.0","Line of Business":{"code":"LOB45","label":"Automation"}}]

Document Information

Modified date:
28 October 2021

Tips

PM60436: MESSAGES ARE NOT DISTRIBUTED TO LOAD BALANCED SERVICE INTEGRATION BUS MESSAGE ENGINES

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

R800 PSY

Document Information

Share your feedback

Need support?