How to Promote an Additional Domain Controller to a Primary Domain Controller ,in case existing PDC is down

In Additional Domain Controller(ADC)
Firstly you have to Transfer Five Server Roles.
1.Schema (ADS,Objects)
2.RID Master
3.Infrastructure Master
4.PDC
5.Domain Naming Master.
In cmd prompt
>ntdsutil
>ntdsutil>roles
fsmo master>connections
Server connections>connect to domain "DOMAIN NAME"
>Quit
Fsmo maintanance> seize schema master
>seize domain naming master
>seize rid master
>seize pdc
>seize infrastructure master
>quit
>ntdsutil>quit
exit
Now your ADC promoted to PDC