IT27001: POSSIBLE TRAPS AND/OR EBADF (ERRNO 9) ERRORS WHEN USING UTL_MAIL.SEND() AND THE ROUTINES FAILS

Db2 Version 11.1 Mod 4 Fix Pack 5 for Linux, UNIX, and Windows

APAR status

• Closed as program error.

Error description

• Db2 might crash with errors like the following in the
  db2diag.log, pointing to a possible Disk issue, although there
  is no relevant disk problem.
  
  FUNCTION: DB2 UDB, oper system services, sqloSystemErrorHandler,
  probe:10
  MESSAGE : ZRC=0x860F000A=-2045837302=SQLO_FNEX "File not found."
  DIA8411C A file "" could not be found.
  CALLED : OS, -, fstat64
  OSERR  : EBADF (9) "Bad file number"
  
  The problem is due to calling UTL_MAIL.SEND() (not limited to
  just this routine)
  When such a routine fails it will attempt to close the 'file
  descriptor' to the
  SMTP server 3 times in a row instead of 1. If something else
  opened a file and got the same  file descriptor in between then
  results can end up in trap or
  errors (EBADF - errno 9) for any system call dealing with a file
  descriptor.
  
  One way to check for this issue is to use traces:
  
    cat > trcmask <<SdS
    add sqlriInvokerTrusted
    add sqleml_utl_tcp_open_connection
    add sqleml_utl_tcp_close_connection
    SdS
  
    db2trc on -f trc.raw -Mfile trcmask
  
  After the problem occurs you should see in the traces 1 call to
  sqleml_utl_tcp_open_connection()
  but 3 calls to sqleml_utl_tcp_close_connection() for the same
  procedure. In the formatted (.fmt)
  trace file you should see that the value of the file descriptor
  in sqleml_utl_tcp_close_connection()
  is the same for all 3 calls.
  
  
  Additional symptoms could include intermittent problem with
  DB2's listener (db2tcpcm) going down and applications receive
  SQL30081 and "Connection Refused".
  
  PID    : 1123456            TID : 1234         PROC : db2sysc 0
  INSTANCE: db2inst1            NODE : 000
  HOSTNAME: TEST
  EDUID  : 3085                EDUNAME: db2tcpcm 0
  FUNCTION: DB2 UDB, common communication, sqlcctcpconnmgr_child,
  probe:2393
  MESSAGE : DIA3202C The TCP/IP call "ioctl(FIONBIO)" returned an
  errno="9".
  
  
  PID    : 1123456            TID : 3342          PROC : db2sysc 0
  INSTANCE: db2inst1            NODE : 000
  HOSTNAME: TEST
  EDUID  : 3342                EDUNAME: db2tcpcm 0
  FUNCTION: DB2 UDB, common communication, sqlcctcpconnmgr_child,
  probe:75
  MESSAGE : DIA3202C The TCP/IP call "select" returned an
  errno="9".
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * ALL                                                          *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Upgrade to Db2 11.1 Mod 4 Fixpack 5 or higher                *
  ****************************************************************
  

Problem conclusion

• First fixed in Db2 11.1 Mod 4 Fixpack 5
  

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:

Fix information

• Fixed component name

  DB2 FOR LUW

• Fixed component ID

  DB2FORLUW

Applicable component levels

• RB10 PSN

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