Logging in to system

This page explains how to login to supercomputing system for the first time.
You will need your account approval and password notification, which are sent when your account has been issued.

In MASAMUNE-IMR system, public key authentication is used in addition to password authentication from a security point of view.
To connect to supercomputing system, you need to go through an SSH server as shown in the following figure.

So you can login to the system in the following steps.

1. Register your public key on the SSH server.
2. Login to the SSH server.
3. Login to front end node of each system.

Node name of each system is as follows:

• Your device on which SSH client software is available.
  
• Documents
  • Account approval
  • Password notification
  • SSH public key registration system manual.

Login to Public key Registration system using User ID and password written in documents, then follow the manual.
Please do not forget your ssh passphrase.
If your public key is Registered successfully, you will get a zip file attached to email.
If you extract it, you will get “id_rsa”. It is a secret key file. Save it in appropriate directory.

The explanation below assumes that id_rsa was saved in:

• C:\Users\username\.ssh\keys\ on Windows 10.
• ~/.ssh/keys/ on MacOS or Linux.

This section finally explains how to login to server with ssh command.
We assume that OpenSSH is installed on your device.
OpenSSH is installed by default on Windows 10 version 1803 or later, MacOS, and many Linux distributions.
If you use Tera Term, please see How to login using Tera Term.
Or, if you use PuTTY, please see How to login using PuTTY.

Make a text file named “config” in ~/.ssh/ directory (C:\Users\username\.ssh\ on Windows) as follows.
Please note that you need to replace “userID” with your user ID string.

Windows

config

Host cms-ssh.sc.imr.tohoku.ac.jp super.sc.imr.tohoku.ac.jp gpu.sc.imr.tohoku.ac.jp
    User userID
Host cms-ssh.sc.imr.tohoku.ac.jp
    HostName cms-ssh.sc.imr.tohoku.ac.jp
    IdentityFile "C:\Users\username\.ssh\keys\id_rsa"
Host super.sc.imr.tohoku.ac.jp gpu.sc.imr.tohoku.ac.jp
    ProxyJump cms-ssh.sc.imr.tohoku.ac.jp
Host super.sc.imr.tohoku.ac.jp
    HostName super.sc.imr.tohoku.ac.jp
Host gpu.sc.imr.tohoku.ac.jp
    HostName gpu.sc.imr.tohoku.ac.jp

Mac, Linux

config

Host cms-ssh.sc.imr.tohoku.ac.jp super.sc.imr.tohoku.ac.jp gpu.sc.imr.tohoku.ac.jp
    User userID
Host cms-ssh.sc.imr.tohoku.ac.jp
    HostName cms-ssh.sc.imr.tohoku.ac.jp
    IdentityFile ~/.ssh/keys/id_rsa
Host super.sc.imr.tohoku.ac.jp gpu.sc.imr.tohoku.ac.jp
    ProxyJump cms-ssh.sc.imr.tohoku.ac.jp
Host super.sc.imr.tohoku.ac.jp
    HostName super.sc.imr.tohoku.ac.jp
Host gpu.sc.imr.tohoku.ac.jp
    HostName gpu.sc.imr.tohoku.ac.jp

Let's try logging in to a front end node of Large-Scale Parallel Computing Server (super.sc.imr.tohoku.ac.jp).
If you use Windows, run cmd.exe. If you are MacOS or Linux user, open the terminal.
Then run the following command.

ssh super.sc.imr.tohoku.ac.jp

You will asked your SSH passphrase and password.

Enter passphrase for key '/home/username/.ssh/keys/id_rsa': {SSH_passphrase}
Password: {initial_password}

When you login to system for the first time, you will need to change your password.

WARNING: Your password has expired.
You must change your password now and login again!
Current Password: {initial_password}
New Password: {new_password}
Retype New Password: {new_password}

If the password has been changed successfully, you will automatically logged out.
Please log in again, and then the following prompt will appear.
Please note that your home directory has a size limit of 500 GB.

Last login: Thu Dec  3 08:55:14 2020 from 130.34.224.22

Disk quotas for user username (uid xxxxx):
     Filesystem    used   quota   limit   grace   files   quota   limit   grace
          /home      0G    500G    550G       -  917739       0       0       -
username@super1:~>

In the next page, you can learn how to transfer files between your device and supercomputing system.