Password-less ssh Connection

When a process is started remotely, ssh is used to launch the processes by default. Without a password-less SSH capability enabled, your password will be requested when launching jobs. A script is provided with the Intel® MPI Library installation package that will automatically generate and distribute SSH keys for a user. The script is named sshconnectivity.exp and is located in the main folder after extracting the tarball. If the script does not work for your system, the keys can be generated and distributed manually by following these steps:

1. Generate a public key

   local> ssh-keygen -t dsa -f .ssh/id_dsa

   When you are prompted for a password, leave it blank by pressing the <enter> key

   Two new files id_dsa and id_dsa.pub are created in the .ssh directory. The latter one is the public key.

2. Distribute the public key to remote nodes

   Go to the .ssh directory. Copy the public key to the remote machines.

   local> cd .ssh

   local> scp id_dsa.pub user@remote:~/.ssh/id_dsa.pub

   Log into the remote machine and go to the .ssh directory on the remote side.

   local> ssh user@remote

   remote> cd .ssh

   Add the client's public key to the known public keys on the remote server.

   remote> cat id_dsa.pub >> authorized_keys

   remote> chmod 640 authorized_keys

   remote> rm id_dsa.pub

   remote> exit

Next time you log into the remote server, you will not be prompted for a password.