Oracle数据库挂了后weblogic的日志，接下来就要具体分析数据库的alert日志才能定位到问题。
<2017-3-24 上午09时27分34秒 CST> <Warning> <JDBC> <BEA-001129> <Received exception while creating connection for pool "CTDataSource": Listener refused the connection with the following error:
ORA-12518,TNS:listener could not hand off client connection > <2017-3-24 上午09时27分34秒 CST> <Info> <JDBC> <BEA-001156> <Stack trace associated with message 001129 follows: java.sql.sqlException: Listener refused the connection with the following error: ORA-12518,TNS:listener could not hand off client connection at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:419)at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:538)at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:228)at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:32)at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:521)at weblogic.jdbc.common.internal.ConnectionEnvFactory.makeConnection(ConnectionEnvFactory.java:350)at weblogic.jdbc.common.internal.ConnectionEnvFactory.createResource(ConnectionEnvFactory.java:236)at weblogic.common.resourcepool.ResourcePoolImpl.makeResources(ResourcePoolImpl.java:1249)at weblogic.common.resourcepool.ResourcePoolImpl.makeResources(ResourcePoolImpl.java:1166)at weblogic.common.resourcepool.ResourcePoolImpl.reserveResourceInternal(ResourcePoolImpl.java:450)at weblogic.common.resourcepool.ResourcePoolImpl.reserveResource(ResourcePoolImpl.java:342)at weblogic.common.resourcepool.ResourcePoolImpl.reserveResource(ResourcePoolImpl.java:329)at weblogic.jdbc.common.internal.ConnectionPool.reserve(ConnectionPool.java:417)at weblogic.jdbc.common.internal.ConnectionPool.reserve(ConnectionPool.java:324)at weblogic.jdbc.common.internal.ConnectionPoolManager.reserve(ConnectionPoolManager.java:94)at weblogic.jdbc.common.internal.ConnectionPoolManager.reserve(ConnectionPoolManager.java:115)at weblogic.jdbc.pool.Driver.connect(Driver.java:150)at weblogic.jdbc.jts.Driver.getNonTxConnection(Driver.java:651)at weblogic.jdbc.jts.Driver.connect(Driver.java:127)at weblogic.jdbc.common.internal.RmiDataSource.getConnection(RmiDataSource.java:364)at cn.gg.top.core.jodd.executor.DBExecutorProvider.getConnection(DBExecutorProvider.java:56)at cn.gg.top.core.base.dao.CoreDAO.getConnection(CoreDAO.java:718)at cn.gg.top.core.base.dao.CoreDAO.executeDefault(CoreDAO.java:688)at cn.gg.top.core.base.dao.CoreDAO.execute(CoreDAO.java:673)at cn.gg.top.core.base.dao.CoreDAO.queryList(CoreDAO.java:374)at cn.gg.top.workbench.message.appservice.WorkbenchMessageAppService.queryAllMessageCount(WorkbenchMessageAppService.java:106)at cn.gg.top.workbench.job.WorkbenchMessageCacheJob.cacheUndoMessageMap(WorkbenchMessageCacheJob.java:115)at cn.gg.top.workbench.job.WorkbenchMessageCacheJob.access$000(WorkbenchMessageCacheJob.java:36)at cn.gg.top.workbench.job.WorkbenchMessageCacheJob$1.run(WorkbenchMessageCacheJob.java:101)at java.util.TimerThread.mainLoop(Timer.java:512)at java.util.TimerThread.run(Timer.java:462) Caused By: oracle.net.ns.NetException: Listener refused the connection with the following error: ORA-12518,TNS:listener could not hand off client connection at oracle.net.ns.NSProtocol.connect(NSProtocol.java:394)at oracle.jdbc.driver.T4CConnection.connect(T4CConnection.java:1056)at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:308)at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:538)at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:228)at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:32)at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:521)at weblogic.jdbc.common.internal.ConnectionEnvFactory.makeConnection(ConnectionEnvFactory.java:350)at weblogic.jdbc.common.internal.ConnectionEnvFactory.createResource(ConnectionEnvFactory.java:236)at weblogic.common.resourcepool.ResourcePoolImpl.makeResources(ResourcePoolImpl.java:1249)at weblogic.common.resourcepool.ResourcePoolImpl.makeResources(ResourcePoolImpl.java:1166)at weblogic.common.resourcepool.ResourcePoolImpl.reserveResourceInternal(ResourcePoolImpl.java:450)at weblogic.common.resourcepool.ResourcePoolImpl.reserveResource(ResourcePoolImpl.java:342)at weblogic.common.resourcepool.ResourcePoolImpl.reserveResource(ResourcePoolImpl.java:329)at weblogic.jdbc.common.internal.ConnectionPool.reserve(ConnectionPool.java:417)at weblogic.jdbc.common.internal.ConnectionPool.reserve(ConnectionPool.java:324)at weblogic.jdbc.common.internal.ConnectionPoolManager.reserve(ConnectionPoolManager.java:94)at weblogic.jdbc.common.internal.ConnectionPoolManager.reserve(ConnectionPoolManager.java:115)at weblogic.jdbc.pool.Driver.connect(Driver.java:150)at weblogic.jdbc.jts.Driver.getNonTxConnection(Driver.java:651)at weblogic.jdbc.jts.Driver.connect(Driver.java:127)at weblogic.jdbc.common.internal.RmiDataSource.getConnection(RmiDataSource.java:364)at cn.gg.top.core.jodd.executor.DBExecutorProvider.getConnection(DBExecutorProvider.java:56)at cn.gg.top.core.base.dao.CoreDAO.getConnection(CoreDAO.java:718)at cn.gg.top.core.base.dao.CoreDAO.executeDefault(CoreDAO.java:688)at cn.gg.top.core.base.dao.CoreDAO.execute(CoreDAO.java:673)at cn.gg.top.core.base.dao.CoreDAO.queryList(CoreDAO.java:374)at cn.gg.top.workbench.message.appservice.WorkbenchMessageAppService.queryAllMessageCount(WorkbenchMessageAppService.java:106)at cn.gg.top.workbench.job.WorkbenchMessageCacheJob.cacheUndoMessageMap(WorkbenchMessageCacheJob.java:115)at cn.gg.top.workbench.job.WorkbenchMessageCacheJob.access$000(WorkbenchMessageCacheJob.java:36)at cn.gg.top.workbench.job.WorkbenchMessageCacheJob$1.run(WorkbenchMessageCacheJob.java:101)at java.util.TimerThread.mainLoop(Timer.java:512)at java.util.TimerThread.run(Timer.java:462) > [ERROR] 2017-03-24 09:33:25 cn.gg.top.core.jodd.executor.DBExecutorProvider (DBExecutorProvider.java:58) - 获取connection失败: weblogic.jdbc.extensions.ConnectionDeadsqlException: weblogic.common.resourcepool.ResourceDeadException: 0:weblogic.common.ResourceException: Could not create pool connection. The DBMS driver exception was: ORA-01034: ORACLE not available ORA-27123: unable to attach to shared memory segment Linux-x86_64 Error: 23: Too many open files in system Additional information: 26 Additional information: 78315524 Additional information: -2147483648