OA31452: TOLERATE USE OF EPHEMERAL UDP SOURCE PORTS FOR ENTERPRISE EXTENDER 09/12/18 PTF PECHANGE

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Allow UDP packets specifying a destination port of 12000-12004
  to specify an ephemeral source port.
  ADDITIONAL SYMPTOMS:
  IST1411I INOP GENERATED
  IST1430I REASON FOR INOP IS XID OR LDLC COMMAND TIMEOUT
  IST259I INOP RECEIVED CODE=01
  IST493I SOFT INOP OVERRIDDEN BY SOFT INOP
  IST619I ID = xxxxx FAILED - RECOVERY IN PROGRESS
  IST590I CONNECTOUT FAILED FOR PU xxxxx ON LINE xxxxxxx
  IST621I RECOVERY SUCCESSFUL FOR NETWORK RESOURCE xxxxx
  IST590I CONNECTIN ESTABLISHED FOR PU xxxxx ON LINE xxxxxxx
  IST607I VARY DIAL FOR xxxxx FAILED - INVALID NODE TYPE OR STATE
  Switched PU T2 does not come active
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All using Enterprise  Extender connections.  *
  ****************************************************************
  * PROBLEM DESCRIPTION: Tolerate use of ephemeral UDP source    *
  *                      ports for Enterprise Extender.          *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  APAR OA29968 added code which verifies the source port for
  inbound EE packets contain a standard EE port address.
  For some EE platforms an ephemeral port may be used as the
  source port when sending packets to z/OS.  Other
  configurations may use NAPT (Network Address Port Translation)
  which may also alter the source EE port to a non-standard
  (not 12000-12004) value.  In these configurations, EE
  connectivity was disrupted when VTAM validated the source
  port.
  
  This APAR has been taken to make this a configurable option.
  This capability may be controlled by a new EEPORTCK start
  option that enables (if YES coded) or disables (if NO coded or
  defaulted) the port checks added by APAR OA29968.
  
  The following documentation changes have been made:
  
  z/OS IBM Communications Server
  SNA Resource Definition Reference
  Chapter 4. Start options
  Summary of start options
  
  Add the following description of new start option EEPORTCK
  to Table 62.
  
  Table 62. Start options that define APPN characteristics.
  
  EEPORTCK        The EEPORTCK start option determines whether
                  VTAM will accept inbound UDP packets which
                  specify an ephemeral source port.
  
  Chapter 4. Start options
  Description of start options
  
  
      |-EEPORTCK=NO-----------|
      |                       |
   >>-+-----------------------+---------------------------------><
      |                       |
      |-EEPORTCK=_ __NO____ __|
                  |__YES___|
  
  For Enterprise Extender, this option determines whether VTAM
  will accept inbound UDP packets, destined to one of the five
  Enterprise Extender ports (defined by IPPORT), which specify
  an ephemeral source port.  This start option is modifiable.
  
  EEPORTCK = NO
  
    This specifies that VTAM will accept inbound UDP packets,
    destined to one of the five Enterprise Extender ports,
    which specify an ephemeral source port.
  
  EEPORTCK = YES
  
    This specifies that VTAM will not accept inbound UDP packets,
    destined to one of the five Enterprise Extender ports,
    which specify an ephemeral source port. If the source and
    destination ports do not match, the packet is immediately
    discarded.
  
    Result:  Some Enterprise Extender platforms use an ephemeral
             source port for EE communications.  Specifying
             EEPORTCK = YES in these configurations may result
             in loss of connectivity to these EE platforms.
             Similar connectivity issues may result if your
             EE communications utilizes NAPT (Network Address
             Port Translation).
  

Problem conclusion

• The new EEPORTCK start option has been implemented as follows:
  
  ISTCICS2 - defines the new start option.
  ISTCICOM - retains whether or not new start option is specified
  ISTCICPP - issues message IST1093I for new start option if
  specified.
  IST1050C - message IST1093I constant added for new start option.
  ISTACMDT - stores current value of the new start option.
  ISTAUCII - bypasses check for matching SOURCE/TARGET ports when
  EEPORTCK=NO.
  ISTAUCLA - included for maintenance purposes only
  

Temporary fix

Comments

APAR Information

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

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

  UA51894 UA51895 UA51896

Modules/Macros

• ISTACMDT ISTAUCII ISTAUCLA ISTCICOM ISTCICPP
  ISTCICS2 IST1050C
  

Fix information

• Fixed component name

  VTAM V4 MVS/ESA

• Fixed component ID

  569511701

Applicable component levels

• R1A0 PSY UA51894

     UP10/02/09 P F002 ®

• R1B0 PSY UA51895

     UP10/02/09 P F002 ®

• R190 PSY UA51896

     UP10/02/09 P F002 ®

Fix is available

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