Cluster connection

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Safety Check : Connecting imposes standard workstation requirements on the workstation you are using. Specifically: a system with an up-to-date operating system and software, a personal session with a strong password, and the systematic locking or disconnection of your session during any absence, even for short durations.

OpenOnDemand

If the OpenOndemand connection does not work: Make an ssh connection first!
Your password may have expired.

OpenOnDemand allows to connect to “MatriCS 3.0” : login01 or login02

Graphic session with OpenOnDemand

  1. Login : login / password on OpenOnDemand
  2. Go to Visu Desktop of Interactive Apps menu
  3. You can change session duration and clic on Launch
  4. When your “job/task” is “running” state, clic on Launch Visu Desktop

Access via ssh

With a terminal under Linux or with Mac OS X Applications->Utilities->Terminal of MacOS X.
Under Windows in a DOS terminal (cmd) provided you have installed the “ssh client” (Addition or remove programs -> Optional features -> OpenSSH client).
The connection is made by the following command:
ssh mylogin@login.matrics.u- picardie.fr

Ssh connection without having to type his password from password

The goal is to be able to connect to the MatriCS computing platform without having to type in your password by creating an ssh key that you then add to your account.

Step 1: Create an ssh key on your machine

  • On your local machine, type the following command:
    ssh-keygen -t rsa
    -> For each question, hit enter. In your .ssh directory, 2 files have been created, namely id_rsa.pub and id_rsa. For the next step, we will use the id_rsa.pub file. Notice the ‘.’ in directory directory name .ssh.

Step 2: Adding the key to your MatriCS account

  • Connect via ssh to the MatriCS calculation platform.
  • Go to the .ssh directory (Don’t forget the . dot in front of ssh): cd ~/.ssh
  • Edit the file authorized_keys. For example, nano authorized_keys
  • Copy the public key, i.e. the content of the id_rsa.pub file that was generated locally on your machine (Attention, be sure to take the content of the file with the extension .pub and when copying, be careful not to add any character.)
  • Paste / Add this key in the authorized_keys file (MatriCS side)
  • Save the authorized_keys file (For example , doing Ctrl+O with nano)

Step 3: Verification of the addition

  • Disconnect from MatriCS via exit.
  • Remake an ssh connection (ssh mylogin@login.matrics.u-picardie.fr). If everything works fine, you should log in without having to enter your password.

WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED

The server fingerprint may have changed! Let’s check if this is not an impersonation!

You received an error message when trying to connect!

ssh -X login@login.matrics.u-picardie.fr
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the ECDSA key sent by the remote host is
SHA256:FGBUgQgMWQ+WlLklzZULx5ygQkfLnpONlg8kPULZPMo.
Please contact your system administrator.
Add correct host key in /home/xxxxx/.ssh/known_hosts to get rid of this message.
Offending ECDSA key in /home/xxxxx/.ssh/known_hosts:106
remove with:
ssh-keygen -f '/home/xxxxx/.ssh/known_hosts' -R 'login.matrics.u-picardie.fr'
Host key for login.matrics.u-picardie.fr has changed and you have requested strict checking.
Host key verification failed.

You have an old SSH fingerprint for the servers on your system. Remove it using the following command:

ssh-keygen -R login.matrics.u-picardie.fr

Connect! Respond ‘yes’ only if the fingerprint is
DSA 1024 SHA256:M1R6R+TbbbDfa6eYDoQZgd3sBLw80ytmWHjsonu+nLs
ECDSA 256 SHA256:oHaCNmdSH8GjJrJUEn0VTJRN8Bdn65TPwyjTWfTAOwo
ED25519256 SHA256:lWDRVGHclNNH0pMfzrpfHG8Z71qejJ4rzxJj5UcoiS0
RSA SHA256:+0iYYyGI5rPUujDEdMEaeKbETlHdqj5xtxxgV6RCwcw

ssh -X votre_login@login.matrics.u-picardie.fr
The authenticity of host 'login.matrics.u-picardie.fr (194.57.107.35)' can't be established.
ED25519 key fingerprint is SHA256:xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx.
This key is not known by any other names.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Warning: Permanently added 'login.matrics.u-picardie.fr' (ED25519) to the list of known hosts.
votre_login@login.matrics.u-picardie.fr's password: