Add on help for linux learner

1.set up a domain addon1.com which should resolve in dns.The mail of

addon1.com should point to gmail mail server.

  $TTL    86400
$ORIGIN sym.com.
@               IN SOA  ns.sym.com.       root.sym.com. (
                                        2011022300              ; serial (d. adams)
                                        900             ; refresh
    

                                  900             ; retry
                                        900             ; expiry
                                        900 )           ; minimum


sym.com.        IN A            192.168.2.158
                       IN NS                ns.sym.com.
                       IN MX   10   gmail.com.
      
ns                   IN A            192.168.2.158

Output:            
[root@158 ~]# host sym.com
sym.com has address 192.168.2.158
sym.com mail is handled by 10 gmail.com.

2)for a sub domain add a entry in your main domain db file

  $TTL    86400
$ORIGIN sym.com.
@               IN SOA  ns.sym.com.       root.sym.com. (
                                        2011022300              ; serial (d. adams)
                                        900             ; refresh
                                        900             ; retry
                                        900             ; expiry
                                        900 )           ; minimum


sym.com.        IN A            192.168.2.158
                 IN NS                ns.sym.com.
ns              IN A            192.168.2.158
sym2             IN A   192.168.2.158 //subdomain entry


goto cd /usr/local/apache2/htdocs/
      mkdir sym2
      vim index.html
goto cd /usr/local/apache2/conf/extra/
     vim httpd-vhosts.conf
Main domain:
    <VirtualHost 192.168.2.158:80>
    #ServerAdmin webmaster@dummy-host.example.com
    DocumentRoot "/usr/local/apache2/htdocs"
    ServerName sym.com
DirectoryIndex index.html
#Redirect / http://www.gmail.com
#DirectoryIndex index.html index.php
    #ServerAlias www.dummy-host.example.com
    #ErrorLog "logs/dummy-host.example.com-error_log"
    #CustomLog "logs/dummy-host.example.com-access_log" common
</VirtualHost>

sub-domain & addon-domain :
<VirtualHost 192.168.2.158:80>
   DocumentRoot "/usr/local/apache2/htdocs/sym2"
    ServerName sym2.com              //addon domain
ServerAlias sym2.sym.com             //subdomain
 </VirtualHost>
restart
lynx sym.com
lynx sym2.com
lynx sym2.sym.com  //addon domain
lynx sym.com/sym2  //sub domain