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PM88666: DMZ secure proxy, when under load, may continue returning 503 even if backend target server is restored from down status.

Fixes are available

8.0.0.8: WebSphere Application Server V8.0 Fix Pack 8
7.0.0.31: WebSphere Application Server V7.0 Fix Pack 31
8.5.5.2: WebSphere Application Server V8.5.5 Fix Pack 2
7.0.0.33: WebSphere Application Server V7.0 Fix Pack 33
8.0.0.9: WebSphere Application Server V8.0 Fix Pack 9
8.5.5.3: WebSphere Application Server V8.5.5 Fix Pack 3
7.0.0.35: WebSphere Application Server V7.0 Fix Pack 35
8.5.5.4: WebSphere Application Server V8.5.5 Fix Pack 4
8.0.0.10: WebSphere Application Server V8.0 Fix Pack 10
7.0.0.37: WebSphere Application Server V7.0 Fix Pack 37
8.5.5.5: WebSphere Application Server V8.5.5 Fix Pack 5
8.5.5.6: WebSphere Application Server V8.5.5 Fix Pack 6
8.0.0.11: WebSphere Application Server V8.0 Fix Pack 11
8.5.5.7: WebSphere Application Server V8.5.5 Fix Pack 7
7.0.0.39: WebSphere Application Server V7.0 Fix Pack 39
8.5.5.8: WebSphere Application Server V8.5.5 Fix Pack 8
8.0.0.12: WebSphere Application Server V8.0 Fix Pack 12
8.5.5.9: WebSphere Application Server V8.5.5 Fix Pack 9
7.0.0.41: WebSphere Application Server V7.0 Fix Pack 41
8.5.5.10: WebSphere Application Server V8.5.5 Fix Pack 10
8.5.5.11: WebSphere Application Server V8.5.5 Fix Pack 11
8.0.0.13: WebSphere Application Server V8.0 Fix Pack 13
7.0.0.43: WebSphere Application Server V7.0 Fix Pack 43
8.5.5.12: WebSphere Application Server V8.5.5 Fix Pack 12
8.0.0.14: WebSphere Application Server V8.0 Fix Pack 14
8.5.5.13: WebSphere Application Server V8.5.5 Fix Pack 13
7.0.0.45: WebSphere Application Server V7.0 Fix Pack 45
8.0.0.15: WebSphere Application Server V8.0 Fix Pack 15
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
8.5.5.14: WebSphere Application Server V8.5.5 Fix Pack 14

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APAR status

  • Closed as program error.

Error description

  • DMZ secure proxy, when under load, may continue returning 503
    even if backend target server is restored from down status.
    

Local fix

  • n/a
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED:  All users of IBM WebSphere Application      *
    *                  Server                                      *
    ****************************************************************
    * PROBLEM DESCRIPTION: Despite the recovery of a previously    *
    *                      failed backend target server,  the      *
    *                      DMZ secure proxy returns HTTP Error     *
    *                      503 - Service unavailable.              *
    ****************************************************************
    * RECOMMENDATION:                                              *
    ****************************************************************
    When there is a failure routing from the proxy  to an endpoint
    the proxy returns an http 503 unavailable error and 2
    asynchronous tasks are created in the proxy:
    1) A task is created in the proxy which repeatedly attempts
    to connect to that endpoint to see if it is available, and if
    so, mark it  available again.
    2) a task created to mark the cluster member unavailable.
    Under heavy load conditions (high number of requests to route)
    many of these tasks are queued and the tasks to mark a member
    unavailable may be processed even after the endpoint becomes
    available again.  The net effect is that the server appears to
    remain unavailable even though the endpoint is available.
    

Problem conclusion

Temporary fix

Comments

APAR Information

  • APAR number

    PM88666

  • Reported component name

    WEBS APP SERV N

  • Reported component ID

    5724H8800

  • Reported release

    700

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2013-05-08

  • Closed date

    2013-09-20

  • Last modified date

    2013-09-20

  • 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

    WEBS APP SERV N

  • Fixed component ID

    5724H8800

Applicable component levels

  • R700 PSY

       UP

  • R800 PSY

       UP

  • R850 PSY

       UP



Document information

More support for: WebSphere Application Server
General

Software version: 7.0

Reference #: PM88666

Modified date: 20 September 2013