PI62911: ALL SOCKETS APPEAR TO BE ACTIVE BUT NONE OF THEM ARE IN USE.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• WEB-OPEN requests start failing due to the following.
  .
  SO 0202 SOCK  EXIT  - FUNCTION(CREATE)
                        RESPONSE(EXCEPTION)
                        REASON(NO_SOCKET_AVAILABLE)
                        SOCKET_TOKEN(00000000)
  .
  All the Sockets appear to be active but nothing is running on
  them.
  .
  TOKEN    Send ECB Recv ECB Dom Gate Remote IPAddr Port Task
  ____________________________________________________________
  010E0578 00000000 00000000   0   0                   0   0
  013F03FC 00000000 00000000   0   0                   0   0
  01093FDE 00000000 00000000   0   0                   0   0
  012304EC 00000000 00000000   0   0                   0   0
  011C0279 00000000 00000000   0   0                   0   0
  011507FC 00000000 00000000   0   0                   0   0
  .
  It appears the Sockets are being orphaned.
  .
  Looking at all the orphaned sockets reveals the same error
  condition.  They all have -1, 1122 (x'462'), 74580324.
  .
  The explanation of the 74580324 is:
  TCPIP
  Notice: this is an internal error JRSmNoStorage: There is no
  storage available to allocate
  .
  So, it appears there is an issue with TCPIP storage on the
  system, perhaps coinciding with a slight spike in workload.
  This storage issue has caused the creation of a new socket to
  fail.  When the create fails, CICS is not cleaning up the
  control blocks it created.  The WEB OPEN issued by the
  application would fail so there is no way for the application
  to drive any socket cleanup.  Eventually CICS runs out of its
  internal allocation of sockets, even though very few sockets
  are actually being used (we can see in the trace a maximum of
  2 sockets in use at any one time).
  .
  Additional Symptom(s) Search Keyword(s): KIXREVSVR
  

Local fix

• n/a
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All.                                         *
  ****************************************************************
  * PROBLEM DESCRIPTION: Creation of a new SOCKET may fail.      *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  This problem may present as CICS failing to create a TCPIP
  SOCKET because MAXSOCKETS has been reached due to an
  inordinate number of unused and orphaned SOCKETS in CICS.
                                                                 .
  DFHSOCK was driven to create a new TCPIP SOCKET. DFHSOCK
  allocated a socket control block to represent the SOCKET
  and attempted to create the underlying TCP/IP socket via a
  create_tcp call.
                                                                 .
  However, in the reported problem, the create_tcp call failed
  due to a storage issue in TCPIP.  This resulted in the SOCKET
  being orphaned and unusable but still occupied a SOCKET slot
  set by the MAXSOCKETS SIT parameter.  When the number of
  orphaned SOCKETs reached the MAXSOCKETS value then CICS was
  unable to create any more and applications requiring them
  failed, message DFHSO0126 was issued on the console.
                                                                 .
  Keywords: SO0126 msgDFHSO0126
  

Problem conclusion

• DFHSOCK has been modified such that in the aforementioned
  scenario, CICS will properly backout the socket thus preventing
  it being orphaned.
  

Temporary fix

• FIX AVAILABLE BY PTF ONLY
  

Comments

APAR Information

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

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

  PI66400 UI40000

Modules/Macros

• DFHSOCK
  

Fix information

• Fixed component name

  CICS TS Z/OS V5

• Fixed component ID

  5655Y0400

Applicable component levels

• R900 PSY UI40000

     UP16/08/18 P F608

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.