Installing Oracle XE on a Centos based VPS

This is a summary of the steps I followed in order to be able to install Oracle XE 10g on my Centos Virtual Private Server (VPS) hosted by eapps.com.


Update: A more recent post is available concerning the installation of Oracle XE 11g in a similar environment.

The basic idea is based on the steps described in this blog entry.
The main problems that had to be addressed were the following:

1. Lack of swap space
2. Setting apex to be serviced on a port other than 8080.

So here are the steps to run as root:

1. Download the rpm from here. I have used the Universal version (oracle-xe-univ-10.2.0.1-1.0.i386.rpm).
2. Install yum (using Add Application from the Control Panel).
3. Install packages for cpio and libaio with these commands:
   1. yum install libaio
   2. yum install cpio
4. Extract the contents of the rpm into a temporary folder:
   1. rpm2cpio oracle-xe-univ-10.2.0.1-1.0.i386.rpm > oracle-xe-univ-10.2.0.1-1.0.i386.cpio
   2. cpio -idv < oracle-xe-univ-10.2.0.1-1.0.i386.cpio
5. At this point the rpm contents have been extracted and we are ready to copy them to the appropriate locations:
   1. # cp -R ./usr /
   2. # cp -R ./etc /
6. Make the following additions/changes to users/groups using the Control Panel:
   1. Create a group and name it dba.
   2. Create a new user (oracle) with dba as its primary group:
   3. Add root to the dba group.
7. Give the ownership of the /user/lib/oracle to this user :
   chown -R oracle:dba /usr/lib/oracle
   
8. Edit the nls_lang.sh script and replace #!/bin/sh by #!/bin/bash
9. Run the oracle_env.sh to simplify the process:
   . /usr/lib/oracle/xe/app/oracle/product/10.2.0/server/bin/oracle_env.sh
   
10. Change the user rights on the oracle binary :
    1. # chmod u+s $ORACLE_HOME/bin/oracle
    2. # chmod g+s $ORACLE_HOME/bin/oracle
11. Set the desired size of SGA and PGA (in the scripts they appear as substitution variables %sga_target% and %pga_aggregate_target%):
    1. # cd /usr/lib/oracle
    2. Find two (2) files using substitution variables using this: # find . -exec grep "%sga_" '{}' \; -print
    3. Replace the variables in these files with their desired values. I have used the following values:
       1. sga_target=246579200 (= 200 MB)
       2. pga_aggregate_target=67108864 (=64 MB)
12. At this point oracle software is in the correct location and we are ready to run database creation and configuration scripts. Start by executing:
    # /etc/init.d/oracle-xe configure
    
13. I have used the default port (1521) for the listener. However we need to use a port other than 8080 for apex since port 8080 is already used by Tomcat. The port of choice was 8084.

For the rest of the steps open a new shell and login as oracle. Continue with the following steps:

1. Connect internally to oracle using sqlplus to change the XDB HTTP port and register the instance with the listener (this may not be necessary but just in case):
   1. sqlplus / as sysdba
   2. SQL> EXEC DBMS_XDB.SETHTTPPORT(8084);
   3. SQL> alter system register;
2. That's all. You may want to restart oracle. Use the following to stop/start it:
   1. /etc/init.d/oracle-xe stop
   2. /etc/init.d/oracle-xe start
3. At this point if you check your listener it should look like this:
   # lsnrctl status
   
   LSNRCTL for Linux: Version 10.2.0.1.0 - Production on 22-DEC-2008 08:19:09
   
   Copyright (c) 1991, 2005, Oracle. All rights reserved.
   
   Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC_FOR_XE)))
   
   STATUS of the LISTENER
   
   ------------------------
   
   Alias LISTENER
   
   Version TNSLSNR for Linux: Version 10.2.0.1.0 - Production
   
   Start Date 22-DEC-2008 08:18:30
   
   Uptime 0 days 0 hr. 0 min. 39 sec
   
   Trace Level off
   
   Security ON: Local OS Authentication
   
   SNMP OFF
   
   Default Service XE
   
   Listener Parameter File /usr/lib/oracle/xe/app/oracle/product/10.2.0/server/network/admin/listener.ora
   
   Listener Log File /usr/lib/oracle/xe/app/oracle/product/10.2.0/server/network/log/listener.log
   
   Listening Endpoints Summary...
   
   (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC_FOR_XE)))
   
   (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=<your hostname>)(PORT=1521)))
   
   (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=127.0.0.1)(PORT=8084))(Presentation=HTTP)(Session=RAW))
   
   Services Summary...
   
   Service "PLSExtProc" has 1 instance(s).
   
   Instance "PLSExtProc", status UNKNOWN, has 1 handler(s) for this service...
   
   Service "XE" has 1 instance(s).
   
   Instance "XE", status READY, has 1 handler(s) for this service...
   
   Service "XEXDB" has 1 instance(s).
   
   Instance "XE", status READY, has 1 handler(s) for this service...
   
   Service "XE_XPT" has 1 instance(s).
   
   Instance "XE", status READY, has 1 handler(s) for this service...
   
   The command completed successfully
   

Finally, these are the contents of the listener.ora and tnsnames.ora files I am using:

These are the contents of the listener.ora file:

# listener.ora Network Configuration File:

SID_LIST_LISTENER =

(SID_LIST =

(SID_DESC =

(SID_NAME = PLSExtProc)

(ORACLE_HOME = /usr/lib/oracle/xe/app/oracle/product/10.2.0/server)

(PROGRAM = extproc)

)

)

LISTENER =

(DESCRIPTION_LIST =

(DESCRIPTION =

(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC_FOR_XE))

(ADDRESS = (PROTOCOL = TCP)(HOST = <your hostname>)(PORT = 1521))

)

)

DEFAULT_SERVICE_LISTENER = (XE)

These are the contents of the tnsnames.ora file:

# tnsnames.ora Network Configuration File:

XE =

(DESCRIPTION =

(ADDRESS = (PROTOCOL = TCP)(HOST = <your IP>)(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)

)

)

I hope that the above will help other people trying to install Oracle XE on a similar environment.

Kostas