You work as a database administrator for Certkiller .com. In your production 
database， the size of Database Buffer Cache needs to be increased immediately for the current as well as future instances of the database. The Oracle instance has been configured to accommodate any changes in the size of the memory structures. At this is production database， you want to accomplish this task with no impact on the user’s connections. 
Which activity must you have completed before accomplishing this task？（）

You work as a database administrator for Certkiller .com. You decided to manage client and server connections using Local Naming method in Certkiller .com. When you try to connect to the database you get the following error： ERROR： 
ORA-12154：TNS：couldnot resolve service name 
Which network configuration files would you look into to resolve this error？（）