ORA - 12537: TNS: connection closed

Often when active clone to be done to create a new environment, we land up into couple of issues. I will discuss about one issues during this process.

Action : Create a new database on different machine from a source.

Error: ORA - 12537: TNS: connection closed


In order to duplicate the environment was using below

rman log /tmp/duplicate.log

connect target sys/<password>@<source tns alias>

connect auxiliary sys/<password>@<target tns alias>

run{

allocate channel ch1 device type disk;

allocate channel ch2 device type disk;

allocate channel ch3 device type disk;

allocate channel ch4 device type disk;

allocate auxiliary channel ax1 device type disk;

allocate auxiliary channel ax2 device type disk;

allocate auxiliary channel ax3 device type disk;

allocate auxiliary channel ax4 device type disk;

DUPLICATE TARGET DATABASE TO <TARGET_DBNAME>

FROM ACTIVE DATABASE

NOFILENAMECHECK;

}


While making connection to Auxiliary database received mentioned error ORA - 12537: TNS: connection closed. This error is very generic and will not give you exact cause of the problem. In order to identify detailed error look at the listener log file.

In listener log found following error

TNS-12518: TNS: listener could not hand off client connection

 TNS-12547: TNS: lost contact

  TNS-12560: TNS: protocol adapter error

   Linux Error: 32: Broken pipe

This error above will give sufficient clue to identify something on linux layer and it also mention it's not able to hand off connection to database.

This error usually comes when you have incorrect permission for oracle binary and both listener and database runs as separate user. Which is normally a case when people runs Grid as different use and database as different user.

$ORACLE_HOME/bin/oracle

This permission of above binary should looks like

-rwsr-s--x 1 oracle asmadmin 

If permission is not as above then it needs to be correct as

chmod 6751 $ORACLE_HOME/bin/oracle


Retry the connection and it should work. I many case have seen changing permission as oracle user doesn't work and need root to execute this.


References

DOC Id: 1069517.1 ORA-12537/ORA-12547 or TNS-12518

Comments

Post a Comment

Popular posts from this blog

How to Solve - "WAIT FOR EMON PROCESS NTFNS"

Event Monitor Process in short called as EMON is generally used by oracle to send notification. Often applications uses Database Change Notification process also called as DBCN to be aware of changes in the database, based on these notifications they take further actions. Often clients subscribe to the database and notifications are send as callback to them. In some cases you will notice database sessions are showing wait event "WAIT FOR EMON PROCESS NTFNS" and it can even make your database un-responsive. One observation can be these processes are taking more CPU (may not in be in all cases). As stated EMON process deals with database notification and it's spawn and gets down itself and Administrators have no control on theses processes. Anyone can go through oracle documents to read more EMON functioning process.  EMON uses oracle advanced queues and database queue notifications into them and EMON process these notifications to clients based on their subscriptions. In s
Read more

Query Regression - "OR" Transformation Oracle 19c

Recently while upgrading Oracle Database from version 12.1 to 19.10 found there were couple of queries which was running slow post upgrade. Usually these type of behavior is seen while upgrading to newer version and oracle provide various ways to fix them. The difference between good and bad plan was an introduction of  "MERGE JOIN CARTESIAN" (aka MJC) and that's in where regressed query in 19c taking most of the time. MJC sometimes works for queries but in this case it was clearly not helping.  We had following options here:     1. Copy the profile from 12c to 19c database and it worked, but the problem was not just to specific query but with many similar query. This means profile option is not very attractive in this case.     2. We also tried running query with OFE 12.1 to use the same optimizer features as previous version and query behaves well. Though this option can't be placed as we need to use 19c OFE and can be placed only for testing purpose.           alte
Read more