Automatic logon configuration on Linux OS

1. Regarding to DSA:
a) ssh-keygen -t dsa
b) cat ~/.ssh/id_dsa.pub | ssh <username>@<remote-host> "cat - >> ~/.ssh/authorized_keys"

2. Regarding to RSA:
a) ssh-keygen -t rsa
b) ssh-copy-id <username>@<remote-host>

3. Switching different node
NODE=<node-name>; ssh -q -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -o ConnectTimeout=10 ${NODE}