start:mogon_cluster:access

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Essentially only accounts of the Johannes Gutenberg University can get access.

  • External users can approach us to retrieve more information concerning so-called guest accounts.
  • Internal groups with external members should approach their person in charge of accounts at the deanery of your faculty or at the secretariat of the respective institution.

Since the MOGON clusters are Linux-based systems, remote access is granted via SSH.

The MOGON login nodes are accessible only from the university network. To access MOGON from the outside (e.g. from home) you have to use VPN - please refer to these instructions:
(Outside) access using Unix / (Outside) access using Windows. The latter link also contains information for internal access with Windows.

Login to the login-nodes is mediated by a jump node: Access is done with direct login (ssh) to “mogon”. This name implements a 'Round-Robin-DNS' login to both login nodes of MOGON I, mil01.zdv.uni-mainz.de and mil02.zdv.uni-mainz.de. If for some reason you want to login to a specific login node, you can use this names directly. (or if for some other Reason one of the nodes is broken, and the dns always gives you the wrong, broken one to connect to)

The login nodes of MOGON II are miil01.zdv.uni-mainz.de to miil03.zdv.uni-mainz.de. Projects on MOGON I do not have access to MOGON II automatically. You have to apply for MOGON I and MOGON II separately. Only password-less login is available. You need to have your ssh-key1) on MOGON I to be able to log in to MOGON II.

The accelerators (GPUs) of MOGON II reside within MOGON I infrastructure that is to say you have to login to MOGON I but use your MOGON II account (-A m2_*) to have access to those accelerators.

You need to have your ssh-key on MOGON I to be able to log in to MOGON II. (RSA authentication)!

Your home directory is on the same file system on both clusters. In order to access MOGON II, you need to copy your ssh-key once to your home directory on MOGON I (~/.ssh).

ssh-keygen -t rsa -b 4096 -a 100 -C <YourComment>,HPCGATE,HPCLOGIN

This generates a new private/public RSA key pair with 4096 bits. Then ssh-keygen asks for a name for the key (stay with the default if you don't have a good reason)

Enter a file in which to save the key (/home/you/.ssh/id_rsa): [Press enter] 

After that you have to specify a passphrase - Do not use an empty passphrase!

Enter passphrase (empty for no passphrase): [Type a passphrase]
Enter same passphrase again: [Type passphrase again] 

No access with empty passphrase

We are working on a solution to block SSH-Keys with an empty passphrase.

1)
A neat overview on ssh-keys and how to generate and copy them can be found here.
  • start/mogon_cluster/access.1594808617.txt.gz
  • Last modified: 2020/07/15 12:23
  • by jrutte02