Create a new forest & domain controller under win2k8

PS: Here is the guider to create a simplest DC under windows server 2008.

1. Run "DCPROMO", check "Use advanced modle installation".
   
2. Click "Next" two times. Now, choose as you want, here we choose "Create a new domain in a new foreast", and click "Next".
   
3. Input the FQDN(Full Qualified Domain Name), like "r15tsta222.com". Usually, we use "server name + path".
   It's just like: wow.163.com, "wow" is a subdomain of "163", and it is different from "163.com/wow". Here the name "r15tsta222.com" is like "163.com", it's a root domain and we can also create subdomain like "wow".
   
4. Click "Next", input the domain netBIOS name.(system will provide a default one)
   
5. Click "Next", here the dropdownlist lists the foreast functional level. We can change low functional level to high level, for example we can change "windows 2000" to "windows 2003" or "windows 2008", but we can't change high level to low level. So you can choose "Windows 2000".
   
6. Click "Next", also choose "windows 2000" for domian functional level.
   
7. Click "Next", system will verify if localhost has been installed a dns, and show you the DNS install page.
   
8. Set IPv4 to static IP.
   
9. Click "Next", make sur your IPv4 is static, and because the system also provides IPv6 and it's dynamical Ip now, so maybe system will give you a warring which reminds that you'd better use a static Ip. choose the first option because it doesn't matter with a dynamical IPv6 Ip.
   
10. Another warring "A delegation for DNS server can't be created because the authoritative
    parent zone cannot be found or it does not run Windows DNS server".
    You're seeing this because it points to itself when you choose to install DNS and it's not yet there, so just ignore it. It's a benign error.
    
11. The next page is to set DB, LOG, SYSVOL, we can level it as default, click "Next".
    
12. Set your password, it will be used the next time you log on the dc.
    
13. Click "Next" and wait...
    
14. restart
    
15. Check here: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\ProductOptions
    verify the value of "ProductType" is "LanmanNT", and this means your've successed.