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IV64253: AIX DOES NOT DROP RST RECEIVED OUTSIDE THE TCP ACCEPTABLE WINDOW APPLIES TO AIX 7100-02

A fix is available

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APAR status

  • Closed as program error.

Error description

  • AIX does not drop the RST if it is outside the acceptable
    TCP window. This results in connection closure on aix
    side
    resulting in abnormal tcp connection termination.
    This problem occurs if APAR IV42131 is installed and
    ONLY if the firewall resets the connection.
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:
    * Systems running the 7100-02 Technology Level with
    * bos.net.tcp.client at or between 7.1.2.16 and 7.1.2.18
    ****************************************************************
    * PROBLEM DESCRIPTION:
    * AIX does not drop the RST if it is outside the acceptable
    * TCP window. This results in connection closure on aix side
    * resulting in abnormal tcp connection termination.
    * This problem occurs if APAR IV42131 is installed and
    * ONLY if the firewall resets the connection.
    ****************************************************************
    * RECOMMENDATION:
    * Install APAR IV64253.
    ****************************************************************
    

Problem conclusion

  • TCP code is modified to not to accept such RST packets
    (RST packets outside acceptable TCP window). This will
    cause such RST packets to be dropped. Hence connection will
    not abnormally get terminated.
    

Temporary fix

Comments

  • 6100-08 - use AIX APAR IV59360
    6100-09 - use AIX APAR IV62304
    6100-09 - use AIX APAR IV62304
    7100-02 - use AIX APAR IV64253
    7100-03 - use AIX APAR IV62382
    7100-04 - use AIX APAR IV62478
    

APAR Information

  • APAR number

    IV64253

  • Reported component name

    AIX V7.1

  • Reported component ID

    5765H4000

  • Reported release

    710

  • Status

    CLOSED PER

  • PE

    YesPE

  • HIPER

    NoHIPER

  • Submitted date

    2014-08-29

  • Closed date

    2014-08-29

  • Last modified date

    2016-05-11

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

    IV59360

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

    002PC0Ÿ

Fix information

  • Fixed component name

    AIX V7.1

  • Fixed component ID

    5765H4000

Applicable component levels

  • R710 PSY U865330

       UP15/01/19 I 1000

PTF to Fileset Mapping



Document information

More support for: AIX Enterprise Edition

Software version: 710

Operating system(s): AIX

Reference #: IV64253

Modified date: 11 May 2016