11gr2 grid infrastructure installing root.sh problem

Hello. I try to install GRID infrastructure 11gr2 to my system. But I got error on root.sh . How can I solve this?
Here is my problem.

[root@rac1 grid]# ./root.sh

Running Oracle 11g root.sh script...

The following environment variables are set as:

    ORACLE_OWNER= oracle

    ORACLE_HOME=  /u01/app/12.1.0/grid

Enter the full pathname of the local bin directory: [/usr/local/bin]:

The file "dbhome" already exists in /usr/local/bin.  Overwrite it? (y/n)

[n]: y

   Copying dbhome to /usr/local/bin ...

The file "oraenv" already exists in /usr/local/bin.  Overwrite it? (y/n)

[n]: y