报错：command not found，如果oracle安装正确，说明环境变量没配或者没有生效。

bash-4.1$ sqlplus
bash: sqlplus: command not found

bash-4.1$ vi .bash_profile

#.bash_profile

# Get the aliases and functions
if [ -f ~/.bashrc ]; then
. ~/.bashrc
fi

# User specific environment and startupprograms

export ORACLE_BASE=/home/oracle/app/oracle/product
export ORACLE_HOME=$ORACLE_BASE/11.2.0/dbhome_5
export ORACLE_SID=zjvta
export PATH=$ORACLE_HOME/bin:$PATH:$HOME/bin:/usr/lib

export LD_LIBRARY_PATH=$ORACLE_HOME/lib:/lib:/usr/lib:$LD_LIBRARY_PATH
#export PATH
~

三、使环境变量立即生效（或则重启Linux）

bash-4.1$  source .bash_profile

bash-4.1$ sqlplus
sql*Plus: Release 11.2.0.1.0 Production on Mon Sep 26 01:51:45 2016
Copyright (c) 1982,2009,Oracle.  All rights reserved.

bash-4.1$  sqlplus /nolog
sql> conn /as sysdba
sql> exit

bash-4.1$ lsnrctl start

启动成功，出现启动成功提示。