Db2 Tools for zOS

Db2 Tools for z/OS

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  • 1.  IBM Data Studio 4.1.4 - not able to connect - DB2 on Z/OS from windows 10 client

    Posted Thu January 04, 2024 04:56 PM
    Edited by S V Fri January 05, 2024 01:48 PM

    Hello all,

    I am trying to connect from my laptop to DB2 on Z/OS i.e., from Windows 10 client. It is giving an error. 

    I selected the driver as "IBM Data Server Driver for JDBC and SQLJ (JDBC 4.0) using SSL connectivity"
    I have the location, host, port number, user name, password details.
    I have the Truststore file and the password to it.
     
    When I try to connect, I am getting this error ...
     
    A connection attempt was unsuccessful.
     
    Summary
     
    SQL4499N  A fatal error occurred that resulted in a disconnect from the data source.
     
    Try the following suggestions to help solve the problem:
     
    Check that the location name used is the actual location name and not an alias or database name. Ensure the location name is entered in upper case. 
    Check that the host is a valid name or IP address, and that the port number is valid for communication with the data server.
    Ensure that TCP/IP has been setup properly.
    To further diagnose the problem, return to the Properties section and use the Tracing page to enable tracing. Contact the database administrator and provide the trace and other support information available.
    Full message content: [jcc][t4][2030][11211][4.24.92] A communication error occurred during operations on the connection's underlying socket, socket input stream, 
    or socket output stream.  Error location: Reply.fill() - socketInputStream.read (-1).  Message: The server selected protocol version TLS11 is not accepted by client preferences [TLS12].
     
     
    ...
     
    Stack Trace
     
    com.ibm.db2.jcc.am.DisconnectNonTransientConnectionException: [jcc][t4][2030][11211][4.24.92] A communication error occurred during operations on the connection's underlying socket, socket input stream, 
    or socket output stream.  Error location: Reply.fill() - socketInputStream.read (-1).  Message: The server selected protocol version TLS11 is not accepted by client preferences [TLS12]. ERRORCODE=-4499, SQLSTATE=08001com.ibm.db2.jcc.am.b6.a(b6.java:338)
    com.ibm.db2.jcc.t4.a.a(a.java:572)
     
    ...
     
    Any help on how to resolve is appreciated :-)
     
    Regards
    SV

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    SV
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  • 2.  RE: IBM Data Studio 4.1.4 - not able to connect - DB2 on Z/OS from windows 10 client
    Best Answer

    Posted Fri January 05, 2024 04:18 AM
    Edited by Christoph Theisen Fri January 05, 2024 02:58 PM

    Hi,

    the message indicates that your Db2 for z/OS server tries a TLS handshake with version 1.1 of the TLS protocol. However, your installation of Data Studio requires at least TLS v1.2. You can check this as follows:

    Locate a file named "java.security" in the  ...\jdk\jre\lib\security subdirectory of your Data Studio installation. Search for a string "jdk.tls.disabledAlgorithms". It probably looks like this:

    jdk.tls.disabledAlgorithms=SSLv3, TLSv1, TLSv1.1, RC4, DES, MD5withRSA, DH keySize < 1024, DESede, \
           EC keySize < 224, 3DES_EDE_CBC, anon, NULL, DES_CBC

    which indicates that this JRE which is used by Data Studio does not support TLS v1.1 and older. You could bypass this by removing "TLSv1.1" from that list of disabledAlgorithms. However, since TLSv1.1 is outdated, it is more recommended to configure the AT-TLS policy on the z/OS server side that TLS v1.2 or higher is supported. Ask your z/OS system programmers to change the AT-TLS policy. 

    It may be possible that your old machine was running an older version of Data Studio which tolerated TLS v1.1.

    In any case be aware that IBM recommends migrating away from Data Studio for connections to Db2 for z/OS. Consider Db2 Developer Extension for MS Visual Studio Code and/or Db2 Administration Foundation, based on Zowe. Both tools are free of charge.

    Hope that helps!

    Best regards

    Christoph



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    Christoph Theisen
    Rocket Software
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  • 3.  RE: IBM Data Studio 4.1.4 - not able to connect - DB2 on Z/OS from windows 10 client

    Posted Fri January 05, 2024 01:46 PM
    Edited by S V Fri January 05, 2024 01:49 PM

    Hi Christoph,

    Thank you very much and it worked like a charm. Appreciate your help. 

    Regards

    SV



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    SV
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