4 Replies Latest reply: Dec 17, 2003 5:01 PM by 411405 RSS

    Size Data Unit (SDU) mismatch/Bad packet type/Unexpected packet

    97539
      We are using Oracle 8.1.7.4.0 with the thin client/JDBC Drivers 9.2.0.1.0.

      There was another thread on this topic that had no real resolution, so I am going to give it another try. We have a servlet application that uploads and downloads files into Oracle IFS (blobs). Intermittently (usually under heavy load), we receive a combination of the following exceptions. Does anyone have any ideas on what might be causing these exceptions?:

      1. java.sql.SQLException: Io exception: Size Data Unit (SDU) mismatch
      2. java.sql.SQLException: Protocol violation
      3. java.sql.SQLException: Io exception: Bad packet type
      4. java.sql.SQLException: Io exception: Unexpected packet
        • 1. Re: Size Data Unit (SDU) mismatch/Bad packet type/Unexpected packet
          391072
          Did you find anything? we had the same problem. We are using 9i thin driver connect to 8.1.7 oracle db server on NT 4.0. We got all kinds of errors, SDU mismatch, invalid package length.

          • 2. Re: Size Data Unit (SDU) mismatch/Bad packet type/Unexpected packet
            97539
            The recommendation from Oracle is to move to JDBC/thin 9.2.0.3.

            We haven't tried that yet and we haven't found any other solutions either.
            • 3. Re: Size Data Unit (SDU) mismatch/Bad packet type/Unexpected packet
              9585
              I've got the same problem so i downloaded JDBC 9.2.0.3 But I've got error message again..
              so i checked all Oracle drivers in my CLASSPATH and i saw 8i drivers there!!! I found then in /project-path/WEB-INF/lib/ dir in Tomcat (I running it under JBuilder 9) I think that's JBuilders problem 'cause after each compile they have to delete ALL files from lib dir and then place current project libs only!
              • 4. Re: Size Data Unit (SDU) mismatch/Bad packet type/Unexpected packet
                411405
                I'm experiencing the same problem using Oracle 9.2.0.1, jdk1.4. I was seeing the same kinds of errors (Size Data Unit (SDU) mismatch, Protocol violation, Bad packet type, Unexpected packet) using classes12.jar. After a) reading this post and b) realizing that I was using the wrong driver (classes12.jar is only for jdk1.2 and 1.3), I upgraded to driver 9.2.0.3 (ojdbc14.jar).

                After adding the new driver (I'm using the thin driver), my application is still stalling in the same place - when trying to read a clob (either at clob.length() or clob.getCharacterStream()). The only difference is that now, no exception is thrown.

                I feel like I'm close - but what should have fixed it, is not. There is nothing in the CLASSPATH or anything like that pointing to the old driver. The fact that it used to throw an exception and now does not tells me that the new driver is being used.