SQL Server Clustering

Hi,

I have Active/Passive cluster in my Infra with SQL server 2008 on top of Server 2008.

It has connected with Application server.When ever people are facing problems in Apps end failover and failback of SQL services get the issue resolved.

I just want to know what is happening in the Back end while failover and failback process in terms of application server connectivity.

Regards,

Vinodh Selvaraj