I think I have reached the end of Google, but still not able to find the part number I need to download the license file for IBM Data Server Client 11.5. Not listed here https://www.ibm.com/support/pages/db2-version-111-activation-key-part-numbers and I start to get tired of the message
LIC1407N You are trying to register an invalid license certificate file
Update
The client will be serving a set of .Net applications hosted on IIS. They are dependent on the db2 catalog konfig 'test' (and 'prod'). The db2 catalog commands is successfully, but when I want to verify the connection to db2 using command
db2 connect to TEST user TESTUSER
I get (when applying the valid password)
SQL1598N An attempt to connect to the database server failed because of a
licensing problem. SQLSTATE=42968
If I type a password I know is wrong I get
D:\IBM\SQLLIB\BIN>db2 connect to TEST user TESTUSER
Enter current password for CFFSAFI:
SQL30082N Security processing failed with reason "24" ("USERNAME AND/OR
PASSWORD INVALID"). SQLSTATE=08001
So the first error with correct password and the last one with the wrong, to my knowledge it confirmes that I'm able to connect to db2
Which is explained here https://www.ibm.com/support/pages/sql1598n-error-connecting-mainframe-db2-ibm-data-server-driver-even-though-db2-connect-license-file-exists-license-directory-install-path (I do not have a license file in the path)
D:\IBM\SQLLIB\BIN>db2licm.exe -l
Product name: "IBM Data Server Client"
Product identifier: "db2client"
Version information: "11.5"
Got it, as explained here SQL1598N error connecting to mainframe DB2 from IBM Data Server Driver even though DB2 Connect license file exists in the license directory of the install path
I did as explained, found the activation key for IBM DB2 Connect Unlimited Edition for System z - Activation 11.5 for Linux, UNIX and Windows Multilingual whic is CC1V0ML and downloaded it and added it - restartet and voila
You don’t need to apply any license to a Db2 client. Db2 Clients are not licensed.