OW04972: MAX LOGONS FOR D NET STATS INCORRECT

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• When a D NET STATS display is done after a CP-CP session is
  brought up over an APPN host-to-host channel connection, on
  a VSE operating system, the value shown for maximum number of
  logons changes from 0 to 4.  After an LU-LU session is started,
  "maximum number of logons" changes from 4 to 6.  When the same
  configuration is brought up for MVS, the value goes from 0 to
  2 when the CP-CP is started and to 3 when an LU-LU session is
  started.  This inconsistency is confusing.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All VTAM users.                              *
  *                                                              *
  *                                                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: 1) The value displayed for Maximum      *
  *                         Number of Logons when a              *
  *                         D NET,STATS command is entered       *
  *                         on an MVS system is different        *
  *                         from the value for the same          *
  *                         statistic when the same command      *
  *                         is entered on a non-MVS system,      *
  *                         despite the fact that the same       *
  *                         configuration has been brought       *
  *                         up and the same number of            *
  *                         sessions has been activated.         *
  *                                                              *
  *                      2) Since the value for Maximum          *
  *                         Number of Logons varies              *
  *                         according to the number of           *
  *                         sessions activated, the              *
  *                         value displayed is not really a      *
  *                         "maximum" -- "maximum" implies       *
  *                         an upper limit.                      *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  1) When a D NET,STATS command is entered, the modules
     that process the command are actually calculating
     (for the statistic identified by function id 64)
     the current number of session partners, not the
     maximum number of logons.  The maximum number of
     logons, as a statistic, is virtually impossible
     to determine accurately.  Operating system versioning
     code in one of these modules resulted in VM and VSE
     systems accurately calculating the current number of
     session partners by calculating the total number of
     applications, LUs, and cross-domain resources in
     session.  This same versioning code made MVS
     systems inaccurately make this calculation by counting
     only applications in session.
  
  2) The fact that the displayed statistic varies according
     to the number of sessions established makes sense in
     view of the fact that what is really being counted is
     the current number of session partners, not the maximum
     number of logons.
  

Problem conclusion

• 1) The versioning code that prevented the current
     number of session partners from being accurately
     calculated on MVS systems has been removed.  As
     is the case for VM and VSE systems, the total
     number of applications, LUs, and CDRSCs will be
     calculated.
  
  2) MSGIST1127I displays the value for the function id
     64 statistic when a D NET,STATS,TYPE=VTAM command
     is displayed.  The text displayed in this message
     will be changed from "MAXIMUM NUMBER OF LOGONS" to
     "CURRENT NUMBER OF SESSION PARTNERS".  This change
     will require a new entry for function id 64 in
     VTAM V4R2 MESSAGES AND CODES (SC31-6493-00).
     This entry should read:
  
        64 value = CURRENT NUMBER OF SESSION PARTNERS
          value represents the total number of LUs,
          applications, and cross-domain resources that
          are currently in session.
  
     In addition, this message change requires that
     the current example of D NET,STATS,TYPE=VTAM output
     in VTAM V4R2 OPERATION (SC31-6495-00) be replaced with
     a new example that shows the text "CURRENT NUMBER OF
     SESSION PARTNERS".  The current example shows
     the text "MAXIMUM NUMBER OF LOGONS".
  
  3) The Estimating Storage for VTAM diskette (SK2T-2007-00)
     takes the value for function id 64 from
     D NET,STATS,TYPE=VTAM output saved in a file, uses that
     value (the current number of session partners) as
     an approximation to the maximum number of logons, and
     then calculates, on the basis of that value as well as
     other inputs, the total amount of storage consumed by
     VTAM.  That program's help panels will need to be modified
     to indicate that the current number of session partners is
     only a rough approximation to the maximum number of logons,
     but that it is still the best available approximation.
  

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:

  UW07518

Modules/Macros

• ISTNOCD3 ISTNOCSP IST1200C
  

Fix information

• Fixed component name

  VTAM V4 MVS/ESA

• Fixed component ID

  569511701

Applicable component levels

• R201 PSY UW07518

     UP94/07/28 P F407

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.