If we have default php installation in RHEL 4u6, and we need to reinstall with php5 with oracle client supported. Uninstall all PHP4 rpm rpm -qa | grep php rpm -e php-* Install PHP5 rpm rpm -ivh php-common-5*.rpm rpm -ivh php-cli-5*.rpm rpm -ivh php-5*.rpm rpm -ivh sqlite-3*.rpm rpm -ivh sqlite2-*.rpm rpm -ivh php-pdo-5*.rpm rpm -ivh php-oci8-5*.rpm Install InstantClient mkdir -p /opt/oracle/instantclient cd /opt/oracle/instantclient unzip instantclient-basic-linux32-10.2.0.3-xxx.zip unzip instantclient-sdk-linux32-10.2.0.3-xxx.zip echo /opt/oracle/instantclient/instantclient_10_2 >> /etc/ld.so.conf ldconfig cd /opt/oracle/instantclient/instantclient_10_2 ln -s libclntsh.so.10.1 libclntsh.so ln -s libocci.so.10.1 libocci.so ln -s libclntsh.so.10.1 libclntsh.so.11.1 Install oci8 cd /usr/local/src tar xzf oci8-x.x.x.tgz cd oci8-x.x.x phpize ./configure --with-oci8=shared,instantclient,/opt/oracle/instantclient/instantclient_10_2 make make install Restar...