just found this on a CA-site, perhaps it helps:
For DB2, use the DB2 command -DISPLAY DDF to determine the appropriate
value to use for the PassTicket application name.
If GENERICLU is not
defined, replace applid with the second part of the LUNAME.
If GENERICLU is defined, use the second part of GENERICLU.
If neither LUNAME or GENERICLU are defined, use the value of the
IPNAME.
Sample output from the -DISPLAY DDF command follows:
LOCATION LUNAME GENERICLU
DA0GPTIB example.text1 example.text2
TCPPORT=5122 SECPORT=5193 RESPORT=5124 IPNAME=-NONE
In the sample
output, text1 and text2 represent the LUNAME and GENERICLU name,
respectively. Note: When issuing a DB2 command from the z/OS
console, replace the hyphen (-) with the specific command prefix for
the DB2 region.