Setting up password-less ssh

  • NOTE: All SBGrid bound Servers and Workstations on the SBGrid network in the Longwood area require 'pub' key to be uploaded to our. authentication servers. Please follow the steps named "Generate SSH Keys" and "For Systems on the SBGrid network at Longwood" below.

    Off Quad systems (at MCB, HU, Tufts, Genzyme) please following the steps named "Generate SSH Keys" and "For Off-Quad SBGrid Systems" below.

Generate SSH Keys

  1. Generate ssh key-pair for local workstation: ssh-keygen -t rsa ; accept default options and hit return when prompted for passphrase.

For Off-Quad SBGrid Systems

  1. Copy public key (~/.ssh/id_rsa.pub) to remote system: scp ~/.ssh/id_rsa.pub remotesys:~/ If this is the first connection to the remote system, type yes to accept the remote system key.
  2. Login to remote system, configure remote system to trust public key:

    • ssh remotesys
    • create ~/.ssh if it doesn't exist: mkdir ~/.ssh
    • cat ~/id_rsa.pub >> ~/.ssh/authorized_keys
    • chmod 700 ~/.ssh
    • chmod 640 ~/.ssh/authorized_keys
  3. Logout of remote system, and repeat login to check that everything works correctly. If so, ~/id_rsa.pub can be removed from the remote system.

For Systems on the SBGrid network at Longwood

There is no need for ~/.ssh/authorized_keys, the file is ignored on all our linux systems on the SBGrid network at Longwood. The 'pub' key must be uploaded to our authentication servers. These examples assume you copied the pub key to your Linux home directory, you can also copy and paste the entire contents of the .pub file between systems.

You will need to run these commands on crystal.harvard.edu. If you are a Consortium member use shell.sbgrid.org.

ipa user-mod $USER --sshpubkey="$(cat ~/.ssh/id_rsa.pub)"

Or for multiple keys

ipa user-mod $USER --sshpubkey="$(cat ~/.ssh/id_rsa.pub)" --sshpubkey="$(cat ~/.ssh/id_ed25519.pub)"\
 --sshpubkey="$(cat ~/.ssh/othersystem_id_rsa.pub)"

If you are using csh/tcsh shell

ipa user-mod $USER --sshpubkey="`cat ~/.ssh/id_rsa.pub`"

If you get a 'Kerberos Credential' error you will need to enter the following command, type your password and try again.

kinit $USER

Note: The 'ipa' command is not available on most workstations, connect to crystal.harvard.edu and perform the commands there.