Access to the JHPCE cluster is provided via SSH. SSH allows you to establish a secure, encrypted connection between your laptop and a remote computer, and run a shell on that remote computer. In our case, the remote computer is the login node of the cluster, jhpce01.jhsph.edu
How you initiate the ssh connection is going to depend on what type of local laptop or desktop you are using. If you are on a Mac computes, you can start a Terminal (In Finder, Go->Utilities->Terminal), which allows you to run a Unix shell on you Mac, and from that shell use the builtin “ssh” command to connect to the cluster. On a Windows system you will need to install an ssh client. We recommend MobaXterm https://jhpce.jhu.edu/knowledge-base/mobaxterm-configuration/ ) but you can also use Putty or the Windows Subsystem for Linux which is available in newer versions of Windows 10.
Typically SSH has depended on standard Unix userid/passwords to authenticate a user. Unfortunately, it is well known that passwords are hopelessly obsolete and we cannot depend on a simple string of characters for protection. To that end, we require that all users use enable 2 Factor Authentication on their JHPCE account. For more information on 2 Factor authentication for your account, please refer to our page on 2 Factor Authentication
When ssh-ing into the cluster you will be prompted for 2 pieces of information. First you will be prompted for “Verification Code:”, and for this you will enter the 6 digit number from the Google Authenticator app, and then press <ENTER>. Next you will be prompted for “Password:” and for this you this will use a traditional password that only you know, and then press <ENTER>. Note that when entering your Verification Code and Password, your cursor will not move when you type, so it may look like nothing is happening, but rest assured that whatever you are typing is being received. If you have never accessed the cluster before, and “Initial Verification Code” and “Initial Password” will be provided to you during your JHPCE Cluster Orientation session.
If you only get prompted for “Password” and not “Verification Code”, you are likely using the wrong login ID. Your login ID is provided to you during the JHPCE orientation, and it is not the same as your JHED ID.
If you have entered your credentials correctly, you will see a login banner for the JHPCE cluster, and you will be sitting at a shell prompt on the login node. However, if you are prompted for “Verification Code:” again, you likely mistyped either your password or Verification Code, and you should wait until your Google Authenticator code changes (it changes every 30 seconds) and you will need to try logging in again.
If you have tried several times to login, and you try to ssh again and get a “Connection Refused” message, you will need to wait 30 minutes before trying to login again. We have a security mechanism in place that will temporarily block additional login attempts after a number of failed login attempts, but this block will clear after 30 minutes. If you continue to have login issues, please contact email@example.com.
We also support the use of SSH public/private key authentication to access your account. SSH key pairs enhance security by verifying that the system you are connecting to the cluster from is a trusted computer. By using ssh key, you can avoid having to use your password to login to the JHPCE cluster. For instructions on setting up ssh keypairs, please refer to our page on SSH keys.