My Learning

Database Configuration Assistant is not showing the database and  Configure Database Options and Delete a Database option are greyed out(disabled)  after setting up ORACLE_SID and ORACLE_HOME running dbca is not showing the database and the above options are greyed out. check the oratab file for correct entry for the database we are trying to access from dbca. Give database name and database home path in the oratab file and save it now run dbca to configure the database.

go to the node from where you will be connecting [ source machine ] run ssh-keygen -t dsa or ssh-keygen -t rsa this will generate public and private key when asked for file name and password just press enter so that default file will be created and password will be blank now copy the .pub content to the target machine's authorized_keys file under [username]/.ssh/ ssh-copy-id  -i [pub_file_name] [username]@[targethostname] [it will ask for password to connect to target provide password for this time] ex: ssh-copy-id  -i id_dsa.pub testuser@testserver this command will copy the public key to the target machines user's authorised_keys file location of the authorized_key file is - [user's home folder]/.ssh/ if the above command does not work copy the public key manually to target machine add the copied public key to user's authorized_key file, if it does not exist just create one ex: ssh-copy-id -i id_dsa.pub test@testserver Note: ssh-copy-id comm