%ORACLE_HOME%\network\admin\sqlnet.ora 

NAMES.DIRECTORY_PATH= (TNSNAMES,EZCONNECT)

C:\ora11client\orahome\network\admin>sqlplus system/qqq@//127.0.0.1/DMASLOV

SQL*Plus: Release 11.2.0.1.0 Production on Ср Апр 25 15:01:06 2018

Copyright (c) 1982, 2010, Oracle.  All rights reserved.


Присоединен к:
Oracle Database 11g Release 11.2.0.1.0 - 64bit Production

[oracle@centos Disk1]$ su -
Password: 
[root@centos ~]# cd /home/oracle/Desktop/Disk1/
[root@centos Disk1]# rpm -i oracle-xe-11.2.0-1.0.x86_64.rpm 
/var/tmp/rpm-tmp.P9AHBt: line 257: [: 18446744073692774399: integer expression expected
/var/tmp/rpm-tmp.P9AHBt: line 271: [: 18446744073692774399: integer expression expected
Executing post-install steps...
You must run '/etc/init.d/oracle-xe configure' as the root user to configure the database.

[root@centos Disk1]# /etc/init.d/oracle-xe configure

Oracle Database 11g Express Edition Configuration
-------------------------------------------------
This will configure on-boot properties of Oracle Database 11g Express 
Edition.  The following questions will determine whether the database should 
be starting upon system boot, the ports it will use, and the passwords that 
will be used for database accounts.  Press <Enter> to accept the defaults. 
Ctrl-C will abort.

Specify the HTTP port that will be used for Oracle Application Express [8080]:

Specify a port that will be used for the database listener [1521]:

Specify a password to be used for database accounts.  Note that the same
password will be used for SYS and SYSTEM.  Oracle recommends the use of 
different passwords for each database account.  This can be done after 
initial configuration:
Confirm the password:

Do you want Oracle Database 11g Express Edition to be started on boot (y/n) [y]:

Starting Oracle Net Listener...Done
Configuring database...Done
Starting Oracle Database 11g Express Edition instance...Done
Installation completed successfully.
[root@centos Disk1]# logout
[oracle@centos Disk1]$ sqlplus
bash: sqlplus: command not found...
[oracle@centos Disk1]$ echo $PATH
/usr/lib64/qt-3.3/bin:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin:/home/oracle/.local/bin:/home/oracle/bin
[oracle@centos Disk1]$ su -
Password: 
Last login: Wed Apr 25 21:39:22 MSK 2018 on pts/0
[root@centos ~]# find / -name sqlplus -print
find: ‘/run/user/1000/gvfs’: Permission denied
/u01/app/oracle/product/11.2.0/xe/bin/sqlplus
/u01/app/oracle/product/11.2.0/xe/sqlplus
[root@centos ~]# logout
[oracle@centos Disk1]$ export PATH=$PATH:/u01/app/oracle/product/11.2.0/xe/bin/
[oracle@centos Disk1]$ sqlplus system/qqq@XE
Error 6 initializing SQL*Plus
SP2-0667: Message file sp1<lang>.msb not found
SP2-0750: You may need to set ORACLE_HOME to your Oracle software directory
[oracle@centos Disk1]$ export ORACLE_HOME=/u01/app/oracle/product/11.2.0/xe/
[oracle@centos Disk1]$ sqlplus system/qqq@XE

SQL*Plus: Release 11.2.0.2.0 Production on Wed Apr 25 21:58:15 2018

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


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

SQL> exit
Disconnected from Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production
[oracle@centos Disk1]$ cat $ORACLE_HOME/network/admin/sqlnet.ora
cat: /u01/app/oracle/product/11.2.0/xe//network/admin/sqlnet.ora: No such file or directory
[oracle@centos Disk1]$ cat $ORACLE_HOME/network/admin/tnsnames.ora
# tnsnames.ora Network Configuration File:

XE =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = centos)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = XE)
    )
  )

EXTPROC_CONNECTION_DATA =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC_FOR_XE))
    )
    (CONNECT_DATA =
      (SID = PLSExtProc)
      (PRESENTATION = RO)
    )
  )

[oracle@centos Disk1]$