什么是DISABLE_OOB (Out Of Band Break)

DISABLE_OOB是sqlnet.ora下的一个参数，那么这个参数的用途是啥呢？想必很多人对这个参数不慎了解，或者根本就没有听说过。下面是对What is DISABLE_OOB (Out Of Band Break)? (Doc ID 373475.1)^[1]的简单翻译。

Data exception or break is a function in Oracle NET that allows a transaction to be interrupted before it is completed. It returns both the client and the server to a condition from which they can continue. A break such as Ctrl-C can be sent as part of the normal data stream (inband), or as a separate asynchronous message (outband). An outband break is much faster and interrupts the flow of data.

数据异常或中断是Oracle NET 中的一个功能，它允许一个事务在完成之前被中断。它将客户端和服务器返回到一种可以继续执行的状态。诸如CTRL+C之类的中断可以作为正常数据流（带内）的一部分发送，也可以作为单独的异步消息（带外）发送。带外中断要快得多并且会中断数据流。

Out Of Band Breaks (OOB) are enabled by default provided the underlying protocol supports sending urgent data.

如果底层协议支持发送紧急数据，则默认启用带外中断 (OOB)

If the parameter DISABLE_OOB is set to OFF then it enables Oracle Net to send and receive "break" messages using urgent data provided by the underlying protocol.

如果参数 DISABLE_OOB 设置为 OFF，则Oracle Net 则使用底层协议提供的紧急数据发送和接收“中断”消息。

If turned on, disables the ability to send and receive "break" messages using urgent data provided by the underlying protocol.

如果这个参数打开（设置为ON）的话，则禁用使用底层协议提供的紧急数据发送和接收“中断”消息的能力。

Out of band breaks are communication breaks that occur on the underlying network level. On occasions these break packets can cause the client and server process to become out of sync. By setting DISABLE_OOB=ON you can force both the client and server to use in-band break.

带外中断是发生在底层网络级别的通信中断。有时，这些中断数据包会导致客户端和服务器进程不同步。通过设置 DISABLE_OOB=ON，您可以强制客户端和服务器使用带内中断。

Oracle TWO_TASK layer has break/reset logic to make sure that both the client and server are in sync. The break/reset logic works effectively if Operating System support OOB (out of band breaks), otherwise there might be TWO_TASK error followed by ORA-3113. So, setting the parameter DISABLE_OOB=ON in order to avoid these TWO_TASK/ORA-3113 errors in the above situation makes sense. DISABLE_OOB is set in the sqlnet.ora file. See Note 67983.1 for additional information on this parameter.

Oracle TWO_TASK 层具有中断/重置逻辑以确保客户端和服务器同步。如果操作系统支持 OOB（带外中断），中断/重置逻辑将有效工作，否则可能会出现 TWO_TASK 错误，然后是 ORA-3113错误。因此，设置参数 DISABLE_OOB=ON 可以避免上述情况下的这些 TWO_TASK/ORA-3113 错误是有意义的。DISABLE_OOB 在 sqlnet.ora 文件中设置。有关此参数的更多信息，请参阅注释 67983.1。

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