Public Key Authentication is helpful because it increases security while at the same time allowing you to log in without typing your password. A good reference on setting up Public Key Authentication is here.

For those of you that use openssh to login with Cygwin, here is a helpful reference.

If you would like to be able to ssh between cluster machines without having to use passwords you should be able to do this when just logged in:

cd .ssh
ssh-keygen -t rsa -b 4096 -f id_cluster_rsa

this will generate two file id_cluster_rsa (the private key) and id and ask for a password. for passwordless logins leave it blank

cat id_cluster_rsa.pub >> authorized_keys

Then you when ssh-ing between nodes, you need to tell ssh to use your identity file (private key). There are two methods

1. If you never ssh out of the cluster then

ln --symbolic id_cluster_rsa id_rsa

2. If you ssh from the cluster to non-cluster machines and use different keys when connecting to different machines (a good security practice), then you can also create a ~/.ssh/config file which will use that particular key for econ hosts then you don't have to do a ssh -i

 Host econ0
  HostName econ0
  User putyourusernamehere
  IdentityFile ~/.ssh/id_cluster_rsa
 Host econ1
  HostName econ1
  User putyourusernamehere
  IdentityFile ~/.ssh/id_cluster_rsa
 Host econ2
  HostName econ2
  User putyourusernamehere
  IdentityFile ~/.ssh/id_cluster_rsa
etc.