我在连接 JDBC 到 Oracle 11g 时遇到了这个奇怪的问题。这周一突然开始发生,我或团队都没有意识到任何设置更改。阅读 Stackoverflow 和 Oracle 论坛(请参阅底部的链接)我了解到在 linux 64 位机器上生成随机字节存在问题。它导致我尝试了几件事,不幸的是没有奏效。这是我所知道的所有信息的摘要。
奇怪的是我可以使用 sqlplus 通过终端连接,但不能使用 JDBC。
感谢您的任何想法或帮助,
阿米特
我的设置:
OS: Ubuntu 12.04
Java: Both 7 and 6_45 (Issue is the same)
JDBC: Downloaded from the Oracle official site (see further description down)
Connection behind a Cisco VPN
JDBC 清单:
odbc7.jar:
Manifest-Version: 1.0
Ant-Version: Apache Ant 1.7.1
Created-By: 20.12-b01 (Sun Microsystems Inc.)
Implementation-Vendor: Oracle Corporation
Implementation-Title: JDBC
Implementation-Version: 12.1.0.1.0
Repository-Id: JAVAVM_12.1.0.1.0_LINUX.X64_130403
Specification-Vendor: Sun Microsystems Inc.
Specification-Title: JDBC
Specification-Version: 4.0
Main-Class: oracle.jdbc.OracleDriver
sealed: true
Name: oracle/sql/converter/
Sealed: false
Name: oracle/sql/
Sealed: false
Name: oracle/sql/converter_xcharset/
Sealed: false
odbc6.jar:
Manifest-Version: 1.0
Ant-Version: Apache Ant 1.7.1
Created-By: 20.12-b01 (Sun Microsystems Inc.)
Implementation-Vendor: Oracle Corporation
Implementation-Title: JDBC
Implementation-Version: 12.1.0.1.0
Repository-Id: JAVAVM_12.1.0.1.0_LINUX.X64_130403
Specification-Vendor: Sun Microsystems Inc.
Specification-Title: JDBC
Specification-Version: 4.0
Main-Class: oracle.jdbc.OracleDriver
sealed: true
Name: oracle/sql/converter/
Sealed: false
Name: oracle/sql/
Sealed: false
Name: oracle/sql/converter_xcharset/
Sealed: false
星期五一切仍在工作:
- 我可以启动我的应用程序并与 Oracle DB 建立 Java 连接。
- 从星期一开始,我遇到了这个问题
- 我的旧电脑(Ubuntu 12.04)也是如此,我几乎一周没有碰过这个问题,即使我让它处于工作状态。
使用 SQLPLUS 的终端连接正在工作:
amit@mymachine:/usr/lib/oracle$ sqlplus /@DB_HOST_IP:1521/DB_NAME
SQL*Plus:2014 年 4 月 22 日星期二 11:35:58 发布 12.1.0.1.0 生产版
版权所有 (c) 1982, 2013,甲骨文。版权所有。
连接到:Oracle 数据库 11g 版本 11.2.0.3.0 - 64 位生产
SQL>
但与 JDBC 的连接失败:
DriverManager.getConnection(
"jdbc:oracle:thin:@//DB_HOST_IP:1521/DB_NAME", username,
password);
挂起约 20 秒并抛出:
ava.sql.SQLRecoverableException: IO Error: Connection reset
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:682)
at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:711)
at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:385)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:30)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:558)
at java.sql.DriverManager.getConnection(DriverManager.java:582)
at java.sql.DriverManager.getConnection(DriverManager.java:185)
at OracleJDBC.main(OracleJDBC.java:32)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)
Caused by: java.net.SocketException: Connection reset
at java.net.SocketInputStream.read(SocketInputStream.java:168)
at oracle.net.ns.Packet.receive(Packet.java:311)
at oracle.net.ns.DataPacket.receive(DataPacket.java:105)
at oracle.net.ns.NetInputStream.getNextPacket(NetInputStream.java:305)
at oracle.net.ns.NetInputStream.read(NetInputStream.java:249)
at oracle.net.ns.NetInputStream.read(NetInputStream.java:171)
at oracle.net.ns.NetInputStream.read(NetInputStream.java:89)
at oracle.jdbc.driver.T4CSocketInputStreamWrapper.readNextPacket(T4CSocketInputStreamWrapper.java:123)
at oracle.jdbc.driver.T4CSocketInputStreamWrapper.read(T4CSocketInputStreamWrapper.java:79)
at oracle.jdbc.driver.T4CMAREngineStream.unmarshalUB1(T4CMAREngineStream.java:426)
at oracle.jdbc.driver.T4C8TTIdty.receive(T4C8TTIdty.java:688)
at oracle.jdbc.driver.T4C8TTIdty.doRPC(T4C8TTIdty.java:595)
at oracle.jdbc.driver.T4CConnection.connect(T4CConnection.java:1439)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:486)
... 12 more
从服务器的日志中:
Fatal NI connect error 12170.
VERSION INFORMATION:
TNS for Linux: Version 11.2.0.3.0 - Production
Oracle Bequeath NT Protocol Adapter for Linux: Version
11.2.0.3.0 - Production
TCP/IP NT Protocol Adapter for Linux: Version 11.2.0.3.0 - Production
Time: 22-APR-2014 09:57:45
Tracing not turned on.
Tns error struct:
ns main err code: 12535
TNS-12535: TNS:operation timed out
ns secondary err code: 12606
nt main err code: 0
nt secondary err code: 0
nt OS err code: 0
Client address: (ADDRESS=(PROTOCOL=tcp)(HOST=<my.ip.address>)(PORT=42738))
从两个服务器错误的 Oracle 文档中:
ORA-12535: TNS:operation timed out
Cause: The requested operation could not be completed within the time out period.
Action: Look at the documentation on the secondary errors for possible remedy. See SQLNET.LOG to find secondary error if not provided explicitly. Turn on tracing to gather more information.
ORA-12606: TNS: Application timeout occurred
Cause: A network session did not reach an application-defined stage within the allowed time interval.
Action: This is an error which does not normally appear at the high level. The action to take is application specific, and is detailed in the higher level error description.
我尝试过的解决方案:
-Djava.security.egd=file:///dev/urandom
按照下面的 Stackoverflow 讨论中的建议添加以下系统属性。设置 rng-tools 以“帮助”操作系统的熵生成器。(见链接)
以下代码运行没有问题,产生随机字节数组(无论参数如何
-Djava.security.egd
:
int a = 10000;
while (a-- > 0){
byte[] array = new byte[2048];
new SecureRandom().nextBytes(array);
System.out.println(a);
}
以上似乎都没有改变错误(超时)。
编辑:新尝试:
- 运行我的应用程序,我可以识别导致我出现实时问题的确切查询。这是在读取 1-2kb 大小的 CLOG 列时。
SQL> select secure_params from session_token where id=11065073;
<- 查询卡住了。
重启客户端,
越来越多地更新此特定行中的该字段,如果该字段的大小为 429 个字符,我仍然可以读取该字段,但是当我将其增加到 587 个字符时,它又被卡住了。
SQL> select length( secure_params) from session_token where id=11065073;
LENGTH(SECURE_PARAMS)
---------------------
587
SQL> select secure_params from session_token where id=11065073;
<- 查询再次卡住。
第 4 次尝试让我想到这里可能还有一个额外的问题,因为应用程序能够创建初始连接并从数据库中获取一些短数据,但只有在结果集变得有点胖时才会失败。
编辑结束
链接:
Stackoverflow:Oracle JDBC 间歇性连接问题
Rng 熵生成器:http: //www.howtoforge.com/helping-the-random-number-generator-to-gain-enough-entropy-with-rng-tools-debian-lenny