ORA-12537: TNS:connection closed

[oracle@gasdbadm01 bin]$ cd/u01/PROD/oracle/product/11.2.0.4/bin/

[oracle@gasdbadm01 bin]$ ls -l oracle

-rwsr-s--x 1 oracle asmadmin 240025740 Jun17 2015 oracle

[oracle@gasdbadm01 bin]$ cd$ORACLE_HOME/bin

[oracle@gasdbadm01 bin]$ ls -l oracle

-rwxr-x--x 1 oracle oinstall 240025740Mar 9 10:37oracle

[oracle@gasdbadm01 bin]$ chmod 6751 oracle

[oracle@gasdbadm01 bin]$ ls -l oracle

-rwsr-s--x 1 oracle oinstall 240025740Mar 9 10:37oracle

[oracle@gasdbadm01 bin]$ sqlplussystem/welcome1@dwprod

SQL*Plus: Release 11.2.0.4.0 Production onWed Mar 9 17:52:51 2016

Copyright (c) 1982, 2013, Oracle. All rights reserved.

Connected to:

Oracle Database 11g Enterprise EditionRelease 11.2.0.4.0 - 64bit Production

With the Partitioning, Real ApplicationClusters, Automatic Storage Management, OLAP,

Data Mining and Real Application Testingoptions

SQL> exit

Disconnected from Oracle Database 11gEnterprise Edition Release 11.2.0.4.0 - 64bit Production

With the Partitioning, Real ApplicationClusters, Automatic Storage Management, OLAP,

Data Mining and Real Application Testingoptions

[oracle@gasdbadm01 bin]$ pwd

/u01/DWPROD/oracle/product/11.2.0.4/bin

[oracle@gasdbadm01 bin]$