Avoiding repeating passwords in ssh_config file on CentOS 5

Environment : Server A, 192.168.2.10, server1.localdomain, root, user1 Server B, 192.168.2.20, server2.localdomain, root, user2 Condition : Server A, wanna put file of content in directory /app/web/ to Server B where owner is user1 and will execute by root