PQ86472: OPTIONALLY DISABLE REVERSE NAME LOOKUP FOR FTP LOGGING

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Need to add the capability to disable the getnameinfo() call
  used to create an FTP log record when logging is enabled.
  
  There are many name domains where the administrators have
  chosen not to provide in-addr.arpa domain records for all of
  the IP addresses in the server's scope.  When these records are
  missing, a nontrivial delay can result while the log record is
  built, which occurs before the initial greeting response from
  the server.  This delay can cause failures of the FTP session
  for some network configurations (outside of the scope of the
  z/OS system).
  

Local fix

• - Disable FTPLOGGING (and ANONYMOUSFTPLOGGING).
  
  - Contact DNS Administrator(s) to have them add PTR resource
    records for the affected in-addr.arpa domains.
  
  See Also:
    Requirements MR0227044716 and MR0309044214 originally
    requested this function.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of the IBM Communications Server   *
  *                 for z/OS Version 1 Release 4 and 5 IP: FTP   *
  ****************************************************************
  * PROBLEM DESCRIPTION: Need to add the capability to disable   *
  *                      the getnameinfo() call used to create   *
  *                      an FTP log record when FTPLOGGING in    *
  *                      the FTP server's FTP.DATA is enabled    *
  *                      (set to TRUE).                          *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When FTPLOGGING TRUE is coded in the FTP server's FTP.DATA at
  connection initiation a DNS lookup to resolve the client's host
  name is done.  This can cause significant delays and should be
  modified to be configurable.
  +-------------------------------------------------------------+
  + Please check our Communications Server for OS/390 homepages +
  + for common networking tips and fixes.  The URL for these    +
  + homepages can be found in Informational APAR II11334.       +
  +-------------------------------------------------------------+
  

Problem conclusion

• FTP server has added a new option to FTPLOGGING, TRUENODNS that
  will disable the DNS lookup at connection initiation time.
  
  In addition, a change has been made to the FTP client to issue
  message EZA2892I if secure port is coded on the start parameters
  along with -a or -r.
  
  The following documentation updates will be made.
  ---------------------------------------------------------------
  IBM Communications Server: IP Configuration Reference
  SC318776
  
  Change the FTPLOGGING statement to include a new parameter
  TRUENODNS.
  
  
          _FTPLOGGING FALSE________
     >>__|_________________________|_________________________><
         |_FTPLOGGING__ _TRUE__ ___|
                       |_TRUENODNS_|
                       |_FALSE_|
  
  Parameters
  
  
  
  TRUE
  The FTP server should log FTP session activity.
  
  TRUENODNS
  The FTP server should log FTP session activity, however
  the client hostname lookup done during connection initiation
  will be disabled.  Message EZYFS50I will contain "UNKNOWN"
  for the host name.
  
  FALSE
  The FTP server should not log FTP session activity.
  ------------------------------------------------------------
  IBM COMMUNICATIONS SERVER: IP MESSAGES: VOL 3 (EZY)
  V1R4
  SC318785
  
  Add the following message.
  EZYFT49I Statement statement parameter must be one of the
  following:        list_of_supported_parameters
  
  Explanation: A statement in FTP.DATA is coded with a parameter
  that is not supported.
  
  statement is the statement that is coded incorrectly.
  
  list_of_supported_parameters is a list of parameters that are
  supported for this statement.
  
  
  System Action: The line containing the error is ignored.
  Processing of the FTP.DATA file continues with the next line
  in the file.
  
  User or Operator Response: Contact the system programmer with
  the error message to have the FTP.DATA file corrected.
  
  System Programmer Response: Change statement in FTP.DATA
  file to specify a supported parameter. Refer to z/OS
  Communications Server: IP Configuration Reference for
  information about supported parameters for statements coded
  in FTP.DATA.
  
  Source Data Set: EZAFTPEP
  
  Procedure Name: read_ftpdata()
  
  * Cross Reference between External and Internal Names
  PREFTPCX (EZAFTPCX)  PREFTPLD (EZAFTPLD)  PREFTPLS (EZAFTPLS)
  EZAFTPSM (FTPDMSG )
  

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:

  UQ87654 UQ87655 UQ87656 PQ92772

Modules/Macros

• EZAFTPAS EZAFTPCX EZAFTPCY EZAFTPDM EZAFTPED
  EZAFTPEH EZAFTPEP EZAFTPGM EZAFTPLD EZAFTPLS EZAFTPRX EZAFTPSD
  EZAFTPSM
  

Fix information

• Fixed component name

  TCP/IP V3 MVS

• Fixed component ID

  5655HAL00

Applicable component levels

• R140 PSY UQ87654

     UP04/05/27 P F405

• R149 PSY UQ87655

     UP04/05/27 P F405

• R150 PSY UQ87656

     UP04/05/26 P F405

Fix is available

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