I want to configure cisco router 3645 for dual provider,
1> Router is configured on Lease Line for Intranet ( Internal application access ) and internet both from HQ.
Now we are going to hire ISP line locally from local ISP for internet use seperately, mean when domain user try to access internal application should access from lease line HQ and when he will access internet like google or any site that should access from local ISP.
If am not wrong all internal/intranet related routes will be a specific routes and internet you would be receiving 0.0.0.0 route from ISP. In that case automatically you can access internal applications via leased line and internet related applications via internet.
Say for eg: if your internal range is 10.0.0.0/8 and internet 0.0.0.0 , then if you get any traffic destined to intranet i.e. 10.0.0.0 will go via leased line and internet will go via ISP link.
Also it depends on the routing model of your infrastructure.