sqlplus: error while loading shared libraries: libsqlplus.so: cannot open shared object file: No such file or directory
The minimum configuration to properly run sqlplus from the shell is to set ORACLE_HOME and LD_LIBRARY_PATH. For ease of use, you might want to set the PATH accordingly too.
Assuming you have unzipped the required archives in /opt/oracle/instantclient_11_1:
$ export ORACLE_HOME=/opt/oracle/instantclient_11_1$ export LD_LIBRARY_PATH="$ORACLE_HOME"$ export PATH="$ORACLE_HOME:$PATH"$ sqlplusSQL*Plus: Release 11.1.0.7.0 - Production on Wed Dec 31 14:06:06 2014...
sudo sh -c "echo /usr/lib/oracle/12.2/client64/lib > /etc/ld.so.conf.d/oracle-instantclient.conf";sudo ldconfigfrom https://help.ubuntu.com/community/Oracle%20Instant%20Client
I did solve this error by setting
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$ORACLE_HOME/lib:$ORACLE_HOMEyes, not only $ORACLE_HOME/lib but $ORACLE_HOME too.