#!/bin/sh

LOGIN="user/pass@host:1521"

CREATE_HOSTS_FILE () {
        sqlplus -s $LOGIN <<EOF > hosts.out
        SET HEAD OFF
        SET LINESIZE 120
        SET FEEDBACK OFF
        SELECT
                HOSTNAME, IP
        FROM
                HOSTS
        WHERE
                ACTIVE = 1
/
EOF
} 

CREATE_HOSTS_FILE

# Now we have a file named hosts.out that we can review and then pass to all servers as the "/etc/hosts" file