Logging in our temporary training clusters

Author

Marie-Hélène Burle

To ensure that everybody is using the same environment, software, and packages, we often build temporary training clusters for our courses and workshops. This eliminates endless trouble-shooting that inevitably happens when the courses/workshops attendees install software and packages on their own machines, as well as the many complications that arise when people run different software and packages versions in different OSes and environments.

These virtual clusters mimic the Alliance production clusters, but they have limited resources and only run for the duration of the courses/workshops. We pre-install the packages necessary for particular courses/workshops in them and give the workshops/courses attendees temporary access via SSH.

This section provides instruction on how to log in those clusters.

Step 1: get the info

During the course or workshop, we will give you 3 pieces of information:

  • a link to a list of usernames,
  • the hostname for our temporary training cluster,
  • the password to access that cluster.

Step 2: claim a username

Add your first name or a pseudo next to a free username on the list to claim it.

Your username is the name that was already on the list, NOT what you wrote next to it (which doesn’t matter at all and only serves at signalling that this username is now taken).

Your username will look like userxx—xx being 2 digits—with no space and no capital letter.

Step 3: run the ssh command

 •  Linux and macOS users

Linux users:   open the terminal emulator of your choice.
macOS users:   open “Terminal”.

Then type:

ssh userxx@hostname

and press Enter.

  • Replace userxx by your username (e.g. user09).
  • Replace hostname by the hostname we will give you the day of the workshop.

When asked:

Are you sure you want to continue connecting (yes/no/[fingerprint])?

Answer: “yes”.

 •  Windows users

We suggest using the free version of MobaXterm, a software that comes with a terminal emulator and a GUI interface for SSH sessions.

Here is how to install MobaXterm:

  • download the “Installer edition” to your computer (green button to the right),
  • unzip the file,
  • double-click on the .msi file to launch the installation.

Here is how to log in with MobaXterm:

  • open MobaXterm,
  • click on Session (top left corner),
  • click on SSH (top left corner),
  • fill in the Remote host * box with the cluster hostname we gave you,
  • tick the box Specify username,
  • fill in the box with the username you selected (e.g. user09),
  • press OK,
  • when asked Are you sure you want to continue connecting (yes/no/[fingerprint])?, answer: “yes”.

Here is a live demo.

Step 4: enter the password

When prompted, enter the password we gave you.

You will not see anything happen as you type the password. This is normal and it is working, so keep on typing the password.

This is called blind typing and is a Linux safety feature. It can be unsettling at first not to get any feed-back while typing as it really looks like it is not working. Type slowly and make sure not to make typos.

Then press Enter.

You are now logged in and your prompt should look like the following (with your actual username):

[userxx@login1 ~]$

Troubleshooting

Problems logging in are almost always due to typos. If you cannot log in, retry slowly, entering your password carefully.