ORA-12519, TNS:no appropriate service handler found

OERR: ORA-12519 TNS:no appropriate service handler found

客户端连接间歇性失败，报错ORA-12519

Cause: the listener could not find any available service handlers that are

appropriate for the client connection.

Action: 检查lsnrctl service ，instance已经注册，状态显示ready时，可以连接。

When the listener believes the current number of connections has reached maximum load,

it may set the state of the service handler for an instance to "blocked" and begin refusing

incoming client connections with either of the following errors: ora-12519 or ora-12516

采用服务动态注册的方式，由PMON 通过SERVICE_UPDATE 来得到目前连接情况，但SERVICE_UPDATE 有时间间隔，

所以，listener显示的连接数和当前实际的连接数可能不同。

查询解决方法:

查看一下数据库现有的进程数，是否已经达到参数processes的大小。

1.select count(*) from v$process取得数据库目前的进程数。

2.select value from v$parameter where name = 'processes'取得进程数的上限。

3.如已达到上限，修改initSID.ora中的processes的大小。

4.重新启动数据库到nomount状态下，执行create spfile from pfile并startup open。

要能够通过监听连接数据库，不仅监听要启动，同时监听也要对这个实例有服务才可以。使用指令LSNRCTL STATUS LISTENER_NAME去查看下是否有服务。

ORA-12159: TNS:trace file not writeable

Cause: The trace file to be generated is not writeable by this user.

Action: If the user does not have write permissions in the directory to which the trace file will be written, contact an administrator to get the proper permissions or set the TRACE_DIRECTORY_CLIENT parameter in the net profile (SQLNET.ORA file) to a directory the user can write to.

给你篇我写的课件参考一下。希望有帮助。

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