IBM Support

PM38306: NULLPOINTEREXCEPTION IN ZAIOTCPCHANNEL.JAVA AND POSSIBLE HANG: COM.IBM.WS.TCP.CHANNEL.IMPL.ZAIOTCPCHANNEL.NEWCONNECTIONCOMMON

Fixes are available

7.0.0.19: WebSphere Application Server V7.0 Fix Pack 19
7.0.0.21: WebSphere Application Server V7.0 Fix Pack 21
7.0.0.23: WebSphere Application Server V7.0 Fix Pack 23
7.0.0.25: WebSphere Application Server V7.0 Fix Pack 25
7.0.0.27: WebSphere Application Server V7.0 Fix Pack 27
7.0.0.29: WebSphere Application Server V7.0 Fix Pack 29
6.1.0.47: WebSphere Application Server V6.1 Fix Pack 47
7.0.0.31: WebSphere Application Server V7.0 Fix Pack 31
7.0.0.27: Java SDK 1.6 SR13 FP2 Cumulative Fix for WebSphere Application Server
7.0.0.33: WebSphere Application Server V7.0 Fix Pack 33
7.0.0.35: WebSphere Application Server V7.0 Fix Pack 35
7.0.0.37: WebSphere Application Server V7.0 Fix Pack 37
7.0.0.39: WebSphere Application Server V7.0 Fix Pack 39
7.0.0.41: WebSphere Application Server V7.0 Fix Pack 41
7.0.0.43: WebSphere Application Server V7.0 Fix Pack 43
7.0.0.45: WebSphere Application Server V7.0 Fix Pack 45
6.1.0.41: Java SDK 1.5 SR12 FP5 Cumulative Fix for WebSphere Application Server
6.1.0.43: Java SDK 1.5 SR13 Cumulative Fix for WebSphere Application Server
6.1.0.45: Java SDK 1.5 SR14 Cumulative Fix for WebSphere Application Server
6.1.0.47: Java SDK 1.5 SR16 Cumulative Fix for WebSphere Application Server
7.0.0.19: Java SDK 1.6 SR9 FP2 Cumulative Fix for WebSphere Application Server
7.0.0.21: Java SDK 1.6 SR9 FP2 Cumulative Fix for WebSphere
7.0.0.23: Java SDK 1.6 SR10 FP1 Cumulative Fix for WebSphere
7.0.0.25: Java SDK 1.6 SR11 Cumulative Fix for WebSphere Application Server
7.0.0.27: Java SDK 1.6 SR12 Cumulative Fix for WebSphere Application Server
7.0.0.29: Java SDK 1.6 SR13 FP2 Cumulative Fix for WebSphere Application Server
7.0.0.45: Java SDK 1.6 SR16 FP60 Cumulative Fix for WebSphere Application Server
7.0.0.31: Java SDK 1.6 SR15 Cumulative Fix for WebSphere Application Server
7.0.0.35: Java SDK 1.6 SR16 FP1 Cumulative Fix for WebSphere Application Server
7.0.0.37: Java SDK 1.6 SR16 FP3 Cumulative Fix for WebSphere Application Server
7.0.0.39: Java SDK 1.6 SR16 FP7 Cumulative Fix for WebSphere Application Server
7.0.0.41: Java SDK 1.6 SR16 FP20 Cumulative Fix for WebSphere Application Server
7.0.0.43: Java SDK 1.6 SR16 FP41 Cumulative Fix for WebSphere Application Server
Obtain the fix for this APAR.

Subscribe

You can track all active APARs for this component.

APAR status

  • Closed as program error.

Error description

  • The Control Region may write an FFDC file containing a
    NullPointerException similar to the stack trace below. This
    may be followed cause a number of symptoms including server
    hang and non responsive outbound requests from applications.
    
    FFDC file:
    ----------
    key = java.lang.NullPointerException
    com.ibm.ws.tcp.channel.ZAioTCPChannel 200
    Exception = java.lang.NullPointerException
    Source = com.ibm.ws.tcp.channel.ZAioTCPChannel
    probeid = 200
    Stack Dump = java.lang.NullPointerException
     at
    com.ibm.ws.tcp.channel.impl.ZAioTCPChannel.newConnectionCommon(Z
    AioTCPChannel.java:680)
     at
    com.ibm.ws.tcp.channel.impl.ZAioTCPChannel.readCompletedNewConne
    ction(ZAioTCPChannel.java:524)
     at
    com.ibm.ws.tcp.channel.impl.ZAioTCPChannelCPPUtilitiesInterfaceI
    mpl.readCompletedNewConnection(ZAioTCPChannelCPPUtilitiesInterfa
    ceImpl.java:82)
     at
    com.ibm.ws390.tcp.channel.ZAioTCPChannelCPPUtilities.readComplet
    edNewConnection(ZAioTCPChannelCPPUtilities.java:79)
    
    Dump of callerThis =
    Object type = com.ibm.ws.tcp.channel.impl.ZAioTCPChannel
    com.ibm.ws.tcp.channel.impl.ZAioTCPChannel@33a833a8
    
    Exception = java.lang.NullPointerException
    Source = com.ibm.ws.tcp.channel.ZAioTCPChannel
    probeid = 200
    Dump of callerThis =
    Object type = com.ibm.ws.tcp.channel.impl.ZAioTCPChannel
    com.ibm.ws.tcp.channel.impl.ZAioTCPChannel@33a833a8
    --------
    
    ZAioTCPChannel=all tracing during time of problem will also show
    the NullPointerException:
    
    --
     Trace: 2011/05/02 08:16:38.863 01 t=8C8490 c=UNK key=S2
    (13007002)
       ThreadId: 00000039
       FunctionName:
    com.ibm.ws.tcp.channel.impl.ZAioTCPBaseRequestContext
       SourceId:
    com.ibm.ws.tcp.channel.impl.ZAioTCPBaseRequestContext
       Category: FINEST
       ExtendedMessage: setBuffer:java.nio.DirectByteBuffer[pos=39
    lim=8192
    cap=8192]
     Trace: 2011/05/02 08:16:38.875 01 t=8C8490 c=UNK key=S2
    (13007002)
       ThreadId: 00000039
       FunctionName: com.ibm.ws.tcp.channel.impl.ZAioTCPChannel
       SourceId: com.ibm.ws.tcp.channel.impl.ZAioTCPChannel
       Category: FINE
       ExtendedMessage: ZAioTCPChannel: httpclient-tcp-outbound -
    Exception
    occurred while processing new client connection: ; java.lang.
     NullPointerException
      at
    com.ibm.ws.tcp.channel.impl.ZAioTCPChannel.newConnectionCommon(Z
    AioTCPCh
    annel.java:680)
      at
    com.ibm.ws.tcp.channel.impl.ZAioTCPChannel.readCompletedNewConne
    ction(ZA
    ioTCPChannel.java:524)
      at
    com.ibm.ws.tcp.channel.impl.ZAioTCPChannelCPPUtilitiesInterfaceI
    mpl.read
    CompletedNewConnection(ZAioTCPChannelCPPUtilitiesInterfa
     ceImpl.java:82)
      at
    com.ibm.ws390.tcp.channel.ZAioTCPChannelCPPUtilities.readComplet
    edNewCon
    nection(ZAioTCPChannelCPPUtilities.java:79)
    0Trace: 2011/05/02 08:16:38.876 01 t=8C8490 c=UNK key=S2
    (13007002)
       ThreadId: 00000039
       FunctionName: newConnectionCommon
       SourceId: com.ibm.ws.tcp.channel.impl.ZAioTCPChannel
       Category: FINER
       ExtendedMessage: Exit; rc=-1
    --
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:  All users of IBM WebSphere Application      *
    *                  Server V6.1.0                               *
    ****************************************************************
    * PROBLEM DESCRIPTION: A WebSphere Application Server for z/OS *
    *                      server suddenly stops accepting inbound *
    *                      work immediately after an outbound      *
    *                      channel chain was started.              *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    When a WebSphere Application Server for z/OS server starts a
    channel chain, an internal data structure is updated with
    details of the TCP channel in the chain.  When multiple chains
    (generally outbound chains) are started over time, it is
    possible for this data structure to become corrupted by the new
    outbound TCP channel.  The symptoms will vary depending on how
    the data structure is corrupted.  If an inbound IIOP channel
    chain is corrupted, the server will stop responding to inbound
    IIOP requests without printing any error messages at all.  If
    an inbound HTTP channel chain is corrupted, the server will stop
    responding to new HTTP requests and an FFDC record similar to
    the following will be seen:
    
    java.lang.NullPointerException at
    com.ibm.ws.tcp.channel.impl.ZAioTCPChannel.newConnectionCommon
        (ZAioTCPChannel.java:680) at
    com.ibm.ws.tcp.channel.impl.ZAioTCPChannel.readCompletedNewConne
    ction
        (ZAioTCPChannel.java:524) at
    com.ibm.ws.tcp.channel.impl.ZAioTCPChannelCPPUtilitiesInterfaceI
    mpl.readCompletedNewConnection
        (ZAioTCPChannelCPPUtilitiesInterfaceImpl.java:82) at
    com.ibm.ws390.tcp.channel.ZAioTCPChannelCPPUtilities.readComplet
    edNewConnection
        (ZAioTCPChannelCPPUtilities.java:79)
    
    Although the above FFDC record will only be printed the first
    time the error is seen, the FFDC summary data will show that
    the NullPointerException occurs once per inbound HTTP request.
    

Problem conclusion

  • Code was fixed so that the TCP channel data structure is no
    longer corrupted when multiple channel chains are started.
    
    APAR PM38306 is currently targeted for inclusion in
    Service Level (Fix Pack) 6.1.0.41 of WebSphere
    Application Server V6.1.
    
    Please refer to URL:
    //www.ibm.com/support/docview.wss?rs=404&uid=swg27006970
    for Fix Pack availability.
    

Temporary fix

Comments

APAR Information

  • APAR number

    PM38306

  • Reported component name

    WEBSPHERE FOR Z

  • Reported component ID

    5655I3500

  • Reported release

    610

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2011-05-03

  • Closed date

    2011-05-31

  • Last modified date

    2011-12-02

  • APAR is sysrouted FROM one or more of the following:

  • APAR is sysrouted TO one or more of the following:

    PM38307

Fix information

  • Fixed component name

    WEBSPHERE FOR Z

  • Fixed component ID

    5655I3500

Applicable component levels

  • R610 PSY UK73054

       UP11/11/03 P F111

Fix is available

  • Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.



Document information

More support for: WebSphere Application Server for z/OS
General

Software version: 6.1

Reference #: PM38306

Modified date: 02 December 2011