Connectivity Problems Using VARSUBNETTING In
Static Environment

 
 APAR Identifier ...... PQ46571      Last Changed ........ 01/09/13
 CONNECTIVITY PROBLEMS USING VARSUBNETTING IN STATIC ENVIRONMENT
 
 Symptom ...... IN INCORROUT         Status ........... CLOSED  PER
 Severity ................... 3      Date Closed ......... 01/06/11
 Component .......... 5735FAL00      Duplicate of ........
 Reported Release ......... 320      Fixed Release ............ 999
 Component Name TCP/IP V2 FOR V      Special Notice           HIPER
 Current Target Date ..              Flags
 SCP ...................               FUNCTIONLOSS
 Platform ............
 
 Status Detail: SHIPMENT - Packaged solution is available for
                           shipment.
 
 PE PTF List:
 
 PTF List:
 Release 3A0   : UQ54998 available 01/06/14 (1000 )
 Release 320   : UQ54999 available 01/06/14 (1000 )
 
 Parent APAR:
 Child APAR list: PQ50059
 
 ERROR DESCRIPTION:
 The GATEWAY statement in the TCP/IP server configuration file
 has been coded to make use of VARSUBNETTING, but certain
 networks cannot be reached.  With the GATEWAY statement
 entries that follow:
 
 GATEWAY
 128.90     =              TOK1  DEFAULTSIZE 0.0.252.0  0.0.160.0
 128.90     =              ETH1  DEFAULTSIZE 0.0.255.0  0.0.244.0
 DEFAULTNET 128.190.160.87 TOK1  DEFAULTSIZE 0
 
 hosts on the 128.90.245, 128.90.246, and 128.90.247 networks
 cannot be reached.  Traces show that outbound packets are
 being placed on the ETH1 adapter, instead of the TOK1 adapter
 that is associated with the DEFAULTNET entry.
 
 LOCAL FIX:
 
 PROBLEM SUMMARY:
 ****************************************************************
 * USERS AFFECTED: z/VM TCP/IP LEVEL 320 USERS                  *
 ****************************************************************
 * PROBLEM DESCRIPTION: Incorrect routes chosen when using      *
 *                      variable subnets.                       *
 ****************************************************************
 * RECOMMENDATION: APPLY PTF                                    *
 ****************************************************************
 When using variable subnetting, the routing logic
 may choose an incorrect route. This causes packets
 to go out the wrong interface.
 
 PROBLEM CONCLUSION:
 The FindRoute logic has been changed to check subnet masks
 on route matches.  If the mask of the 'matching' route is
 not equal to the route being tested no match is returned and
 the search continues.
 
 FindSubnetRoutesVisitNode, FindSupernetRoutesVisitNode
 and FillIpRoutingTree routines have been changed to
 handle zero subnet destination addresses.
 
 TEMPORARY FIX:
 
 COMMENTS:
  **** PE01/08/21 FIX IN ERROR. SEE APAR PQ51304  FOR DESCRIPTION
 
 MODULES/MACROS:   MSTCP    TCIPDOW  TCPIP    TCTREEP
 
 SRLS:      NONE
 
 RTN CODES:
 
 CIRCUMVENTION:
 
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