I have established secure shell (SSH) connectivity on my cluster where each node has a public key. However, when I use any secure shell utility on the cluster, I am still prompted for a password. What am I doing wrong?
Assuming that you have set up a NULL “ passphrase” for your login account when using the ssh-keygen utility, for all systems in your cluster, and that you have distributed the public key for each node to all the other nodes (i.e., the public keys reside in the “ ~/.ssh/authorized_keys” file), then check the permissions of your home directory on your cluster. The “group” and “other” permission categories should only have read and execute accessibility for the home directory folder. If you activate a “write” permission setting for either the “group” or “other” categories, SSH will prompt you for the password. Also, the “ ~/.ssh” subdirectory should only have read, write, and execute permission for the login owner.
Note that the expect shell script sshconnectivity.exp will remove the write access capability on the group and other “permission categories” for the user’s home directory folder.