Oracle Solution for Error ora-12505

ORA-12505: TNS:listener does not currently know of SID given in connect descriptor

What triggered the Error:

The listener received a request to establish a connection to a database or other service. The connect descriptor received by the listener specified a SID for an instance (usually a database instance) that either has not yet dynamically registered with the listener or has not been statically configured for the listener. This may be a temporary condition such as after the listener has started, but before the database instance has registered with the listener.

What should we do to fix it:

*- Wait a moment and try to connect a second time. *- Check which instances are currently known by the listener by executing: lsnrctl services *- Check that the SID parameter in the connect descriptor specifies an instance known by the listener. *- Check for an event in the listener.log file.

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