Linux Oracle remotely login with putty + Oracle Home Directory view

login as: root
root@192.168.1.103's password:
Last login: Tue Aug 20 00:04:52 2013 from 192.168.1.105
[root@localhost ~]# /etc/init.d/oracle-xe start
Starting Oracle Net Listener.
Starting Oracle Database 11g Express Edition instance.

[root@localhost ~]# echo $ORACLE_HOME

[root@localhost ~]# echo $ORACLE_HOME

[root@localhost ~]# sqlplus
-bash: sqlplus: command not found
[root@localhost ~]# . /u01/app/oracle/product/11.2.0/xe/bin/oracle_env.sh
[root@localhost ~]# /etc/init.d/oracle-xe start                                                    Oracle Database 11g Express Edition instance is already started

[root@localhost ~]# echo $ORACLE_HOME
/u01/app/oracle/product/11.2.0/xe
[root@localhost ~]# sqlplus

SQL*Plus: Release 11.2.0.2.0 Production on Tue Aug 20 17:52:58 2013

Copyright (c) 1982, 2011, Oracle.  All rights reserved.

Enter user-name: system
Enter password:

Connected to:
Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production