[[File:JUSTUS2_header.png|700px]]


The '''bwForCluster JUSTUS 2''' is the state-wide high-performance compute cluster dedicated to '''Computational Chemistry and Quantum Sciences''' in Baden-Württemberg.

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* Funding for a new Justus3 system has been secured and the procurement of the new system is underway.
* Our ticketing system has been upgraded. Please check out the visual guide on how to create tickets [[BwSupportPortal|here]].
|}
{| style=" background:#eeeefe; width:100%;"
| style="padding:8px; background:#dedefe; font-size:120%; font-weight:bold; text-align:left" | Training & Support
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* [[JUSTUS2/Getting Started|Getting Started]]
* Online Tutorial [https://hpc-wiki.info/hpc/Introduction_to_Linux_in_HPC Introduction to Linux in HPC] (external link)
* E-Learning Course [https://training.bwhpc.de/goto.php?target=crs_629_rcodeM6n48kAUsT&client_id=BWHPC Introduction to JUSTUS2 ]
* [[JUSTUS2/Support|Contact and Support]]
* Send [[Feedback|Feedback]] about Wiki pages
|}

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| style="padding:8px; background:#cef2e0; font-size:120%; font-weight:bold; text-align:left" | User Documentation
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* [[Registration/bwForCluster|Registration]]
* [[JUSTUS2/Login|Login]]
* [[JUSTUS2/Hardware|Hardware and Architecture]]
** [[JUSTUS2/Hardware#Node_Specifications|Node Specifications]]
** [[JUSTUS2/Hardware#Storage_Architecture|File Systems and Workspaces]]

* [[JUSTUS2/Software|Software]]
* [[JUSTUS2/Jobscripts: Running Your Calculations|Jobscripts: Running Your Calculations]]
** [[bwForCluster JUSTUS 2 Slurm HOWTO|Slurm HOWTO]]
* [[JUSTUS2/Visualization|Visualisation]]
* [[Development]]
|}

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| style="padding:8px; background:#d1dadf; font-size:120%; font-weight:bold; text-align:left" | Cluster Funding
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* Please '''[[JUSTUS2/Acknowledgement|acknowledge]]''' the JUSTUS 2 cluster in your publications.
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J Salk:

= Login to JUSTUS 2 =

Prerequisites:

You should already have
* followed the 3-step [[Registration]] procedure.
* [[Registration/bwForCluster/JUSTUS2|created an account]] at the registration server for JUSTUS2.
* [[Registration/Password|set a service password]] for JUSTUS2.
* [[Registration/2FA|set up a time-based one-time password (TOTP)]] for the two factor authentication (2FA)
* and you should connect from an internet address (IP) that is inside your university network (check your hostname/IP with http://displaymyhostname.com/ )

For the last point: You cannot connect directly from a computer at home to JUSTUS2. You either need to use an on-campus computer or to connect to your university via a virtual private network (VPN). Please consult the documentation of your university how to connect to your university via VPN.

== Login to JUSTUS 2 ==

When all prerequisites are fulfilled you can access the bwForCluster JUSTUS 2 for Computational Chemistry and Quantum Sciences via [[ssh]]. Only the secure shell ssh is allowed for login.

From Linux machines, you can log in using

ssh <UserID>@justus2.uni-ulm.de

During log in you must enter the current TOTP value (6-digit number) created with help of the TOTP app on your smartphone and your service password.

To run graphical applications, you can use the -X flag to openssh:

ssh -X <UserID>@justus2.uni-ulm.de

For better performance on slow connections you should use e.g. [[VNC]].

The bwForCluster Chemistry in Ulm has four dedicated login nodes. The selection of the login node is done automatically. If you are logging in multiple times, different sessions might run
on different login nodes.

The names of the four login nodes are justus2-login01.rz.uni-ulm.de, justus2-login02.rz.uni-ulm.de, justus2-login03.rz.uni-ulm.de, justus2-login04.rz.uni-ulm.de.

These names can be used to access a specific one of the login nodes. In general, you should use justus2.uni-ulm.de to allow us to balance the load over the four login nodes.

== About UserID / Username ==

<UserID> of the ssh command is a placeholder for your username at your home
organization and a prefix denoting your organization. Prefixes and resulting user names are as follows:

{| style="border:3px solid darkgray; margin: 5em auto 5em auto;" width="60%"
|-
!scope="row" {{Darkgray}} | Site
!scope="row" {{Darkgray}}| Prefix
!scope="row" {{Darkgray}}| Username
|-
| Freiburg
| fr
| fr_username
|-
|Heidelberg
|hd
|hd_username
|-
|Hohenheim
|ho
|ho_username
|-
|Karlsruhe
|ka
|ka_username
|-
|Konstanz
|kn
|kn_username
|-
|Mannheim
|ma
|ma_username
|-
|Stuttgart
|st
|st_username
|-
|Tübingen
|tu
|tu_username
|-
|Ulm
|ul
|ul_username
|}

== Allowed activities on login nodes ==

The login nodes are the access point to the compute system and its $HOME directory. The login nodes are shared with all the users of the cluster. Therefore, your activities on the login nodes are limited to primarily set up your batch jobs. Your activities may also be:
* compilation of your program code and
* short pre- and postprocessing of your batch jobs.

To guarantee usability for all users of the bwForCluster you must not run your compute jobs on the login nodes. Compute jobs must be submitted as
[[BwForCluster_JUSTUS_2_Slurm_HOWTO|Batch Jobs]]. Any compute job running on the login nodes will be terminated without any notice.


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[[Category:BwForCluster_JUSTUS_2]][[Category:Access]]