Oracle Database Error | ORA-12528 - oracle

When I try to connect to my Oracle database, I get Listener refused the connection with the following error: ORA-12528, TNS:listener: all appropriate instances are blocking new connections. Also, I'm not sure if this means anything but I checked and my database is not mounted.

If the "unregister" did not complete properly, then when you go to
"startup" the next time, since the LISTENER did not unregister the
instance, you receive the error, "ORA-12528: TNS:listener: all
appropriate instances are blocking new connections" since an
"appropriate" instance is already running.
Check the status of the listener by
LSNRCTL> status
One method that should resolve this problem is to restart (bounce) the LISTENER:
LSNRCTL> stop
LSNRCTL> start
Then restart your instance: sqlplus with sysdba privileges
SQL> startup
Make sure all parameters are set.

Related

How can i solve this issue through Sql Developer with Oracle

Status : Failure -Test failed: Listener refused the connection with the following error:
ORA-12518, TNS: listener could not hand off client connection
Please follow below mentioned steps:
1.Processes parameter and verified by the v$resource_limit view.
2.If you are using a shared server, you may increase the number of dispatchers.
3.Check the alert log for any possible errors.
4.Check the swap, memory usage of the OS.
5.Check the Sid name of database
Action: Turn on listener tracing and re-execute the operation. Verify that the listener and database instances are properly configured for direct handoff.

ORA-03135: connection lost contact

I am getting the error as 'ORA-03135: connection lost contact' from my C# code while making connection to oracle DB. The same job works just fine from our test server. But it failed with ORA-03135: connection lost contact error from prod server.
The C# code use ODAC to connect to oracle DB.
Appreciate your inputs.
Thank you
This error is most likely caused by a firewall blocking the connection request. Check for any firewalls in your network or on the database server and make sure your access rules are configured correctly.
Also check this link for more troubleshooting tips: http://www.dba-oracle.com/t_ora_03135_connection_lost_contact.htm
ORA-03135: connection lost contact tips
What can I do to avoid the ORA-03135 error?
Answer: The oerr utility shows this for the ORA-03135 error:
ORA-03135: connection lost contact
Cause:
1) Server unexpectedly terminated or was forced to terminate.
2) Server timed out the connection.
Action:
1) Check if the server session was terminated.
2) Check if the timeout parameters are set properly in
sqlnet.ora.
The ORA-03135 error is common when connecting remotely when a firewall
terminates the connection.
One solution for the ORA-03135 error is to increase the value of the
sqlnet.ora expire_time parameter in the sqlnet.ora file or to check
for a expire parameter in a SQL*Plus profile.
To diagnose the ORA-03135 error, start by checking to see if the OS
PID still exists, using the "ps -ef | grep" syntax.
Check to see if there is a Network Address Translation (NAT) between
the client and server
In Windows, check to see if a Windows firewall is checking for your
local connections.
...
Also, setting the parameters sqlnet.inbound_connect_timeout and
inbound_connect_timeout_listenername to 0 can stop the ORA-03135
error.

java.sql.SQLRecoverableException: Connection has been administratively disabled by console/admin command. Try later

When our application tries to connect Oracle database, this exception is thrown:
java.sql.SQLRecoverableException: Connection has been administratively disabled by console/admin command. Try later. java.lang.Exception: It was disabled at Tue Oct 20 23:55:14 CEST 2015
But, from Weblogic console the connection test returns OK.
Weblogic version: 12.1.3.0.0
Any explanation is welcome. Thanks
The reason the test works is because that is creating a connection and running a test query. That is not what your code is doing when it is using the data source in an ejb. The code is going through the connection pool and that is what has been marked as bad. There is no solution provided by Oracle that I have found except to: restart the server and that will re-enable the connection pool.
I suspect you have "Test connections on reserve" set because that is when this usually arises. What Weblogic does is: before it returns a connection from the pool it will run a test query, if the test query fails it waits and runs it one more time. If the query fails again it marks the connection as unhealthy. If all the connections in the pool become unhealthy it will mark the pool as disabled and gives you the error message you see: 'Connection has been administratively disabled by console/admin command. Try later.'
In regards to the 'Try Later' part of the error message, as far as I can tell Oracle is wrong about trying again later. I have never seen it recover later.
I'd like to share this article that help me out to understand better my problem:
https://www.techpaste.com/2012/09/connection-administratively-destroyed-reconnect-oracle-weblogic-server/
The “java.sql.SQLException: Connection has been administratively destroyed.” is expected:
the DB was shutdown; even if it was restarted later, the JDBC connection are pointing to DB processes
that have been destroyed.
You need to restart your WebLogic Server to recreate new JDBC connections.
All the current transactions are lost, as the database was shutdown.
High availability of your RDBMS is required to minimize this issue.
Is there any other error before that one ?
Maybe in the log you can find that connection is been closed.
You can avoid this by selecting "Test on Connection Reserve" in the datasource.

Can I stop one instance's listener without affecting other instances on the same server

I have many instances on one Oracle server running 11GR2. I have to fix an issue on one instance. According to Oracle support, I need to shutdown the database and its listener.
lsnrctl stop
lsnrctl start
I can also use svcctl to start and stop a listener on the server as well:
srvctl stop listener -n node_name
I notice that the lsnrctl and srvctl are all based on the server/host/node level. Can I stop one instance's listener without affecting other instances on the same server?
If you do a
lsnrctl status
command, you'll see all of the instances you'd affect by shutting down the listener. Generally you're going to be running only one listener on a server, so you'd shut off network access to all of the databases it serves.
I would not stop the listener in order to bounce one of the instances and adjust a parameter.
The instance will automatically register with the listener when it comes back up.
On the other hand, if we are talking about an inter-process issue you might have to. More details needed.
Remember, already established sessions to your instances will not be affected by a listener outage.

Oracle listener create logon

I would like to prepare listner in another port but I have got problems you can see this in picture with I added below. Also I would like to connect to dabase using this "listener" and check connection in CMD using easy connect.
My username: rafal password:oracle
listener in 1521 is working but in another port I have got problem
"No listener" error indicates either that you're reaching the wrong server, or the right server on the wrong port, or that the listener is not started. I would start by checking that the listener is started, since you can reach the other one.

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