DACHS/Hardware

2026-03-17T17:51:06Z

M Kunzelmann: /* Storage Architecture */

= Architecture of DACHS =
The Datenanalyse Cluster der Hochschulen (DACHS) is a parallel computer with distributed memory connected over Infiniband and Ethernet.
The compute nodes contain at least dual AMD processors, at least 384GB of local memory, 2 TB local NVMe-based disc storage and accelerators as shown in the table below.
With BeeGFS, a fast and scalable filesystem is provided via Infiniband to all both login and all compute nodes.

The Operating System is Rocky-Linux 9.5 (which is based on RHEL).
The setup is kept in-line (with regard to Software, Setup and general usage) and thus mostly equivalent to bwHPC and bwUniCluster in particular.

= Components of DACHS =

{| class="wikitable"
|-
! style="width:9%"|
! style="width:13%"| Compute nodes "L40S"
! style="width:13%"| Compute nodes "H100"
! style="width:13%"| Compute nodes "AMD_APU"
! style="width:13%"| Login
|-
!scope="column"| Availability in Queue
| <code>gpu1</code>
| <code>gpu8</code>
| <code>gpu4</code>
|
|-
!scope="column"| Number of nodes
| 45
| 1
| 1
| 2
|-
!scope="column"| Processors
| AMD EPYC 9254
| AMD EPYC 9454
| AMD MI300A
| AMD EPYC 9254
|-
!scope="column"| Number of sockets
| 2
| 2
| 4
| 2
|-
!scope="column"| Processor frequency (GHz)
| 2.9 Ghz
| 2.75 Ghz
| 2.1 Ghz
| 2.9 Ghz
|-
!scope="column"| Total number of cores
| 48
| 96
| 96
| 48
|-
!scope="column"| Main memory
| 384 GB
| 1536 GB
| 512 GB
| 384 GB
|-
!scope="column"| Local SSD
| 1,92 TB NVMe
| 1,92 TB NVMe
| 1,92 TB NVMe
| 1,92 TB NVMe
|-
!scope="column"| Accelerators
| 1x NVIDIA L40S
| 8x NVIDIA H100
| 4x AMD MI300A
| -
|-
!scope="column"| Accelerator memory
| 48 GB
| 8x 80 GB
| 4x 128 GB
| -
|-
!scope="column"| Interconnect
| IB HDR100
| IB HDR100
| IB HDR100
| IB HDR100
|}
Table 1: Properties of the nodes

== Storage Architecture ==
The system features a 700 TB large BeeGFS filesystem available on login and compute nodes.
Please note: there is a hard file size quota per partner organization and a soft quota per user on Your HOME.
Users will be notified by E-Mail if the quota is to be reached.

Please '''make use''' of the [[Workspaces | Work Space mechanism]] for larger data sets.

DACHS/Hardware

2026-03-17T17:50:37Z

M Kunzelmann: /* Storage Architecture */

= Architecture of DACHS =
The Datenanalyse Cluster der Hochschulen (DACHS) is a parallel computer with distributed memory connected over Infiniband and Ethernet.
The compute nodes contain at least dual AMD processors, at least 384GB of local memory, 2 TB local NVMe-based disc storage and accelerators as shown in the table below.
With BeeGFS, a fast and scalable filesystem is provided via Infiniband to all both login and all compute nodes.

The Operating System is Rocky-Linux 9.5 (which is based on RHEL).
The setup is kept in-line (with regard to Software, Setup and general usage) and thus mostly equivalent to bwHPC and bwUniCluster in particular.

= Components of DACHS =

{| class="wikitable"
|-
! style="width:9%"|
! style="width:13%"| Compute nodes "L40S"
! style="width:13%"| Compute nodes "H100"
! style="width:13%"| Compute nodes "AMD_APU"
! style="width:13%"| Login
|-
!scope="column"| Availability in Queue
| <code>gpu1</code>
| <code>gpu8</code>
| <code>gpu4</code>
|
|-
!scope="column"| Number of nodes
| 45
| 1
| 1
| 2
|-
!scope="column"| Processors
| AMD EPYC 9254
| AMD EPYC 9454
| AMD MI300A
| AMD EPYC 9254
|-
!scope="column"| Number of sockets
| 2
| 2
| 4
| 2
|-
!scope="column"| Processor frequency (GHz)
| 2.9 Ghz
| 2.75 Ghz
| 2.1 Ghz
| 2.9 Ghz
|-
!scope="column"| Total number of cores
| 48
| 96
| 96
| 48
|-
!scope="column"| Main memory
| 384 GB
| 1536 GB
| 512 GB
| 384 GB
|-
!scope="column"| Local SSD
| 1,92 TB NVMe
| 1,92 TB NVMe
| 1,92 TB NVMe
| 1,92 TB NVMe
|-
!scope="column"| Accelerators
| 1x NVIDIA L40S
| 8x NVIDIA H100
| 4x AMD MI300A
| -
|-
!scope="column"| Accelerator memory
| 48 GB
| 8x 80 GB
| 4x 128 GB
| -
|-
!scope="column"| Interconnect
| IB HDR100
| IB HDR100
| IB HDR100
| IB HDR100
|}
Table 1: Properties of the nodes

== Storage Architecture ==
The system features a 700 TB large BeeGFS filesystem available on login and compute nodes.
Please note: there is a hard file size quota per partner organization and a soft quota per user on Your HOME.
Users will be notified by E-Mail if the quota is to be reached.

Please '''do make use''' of [[Workspaces | Work Space mechanism]] for larger files.

DACHS/Hardware

2026-03-17T17:49:50Z

M Kunzelmann: /* Architecture of DACHS */

= Architecture of DACHS =
The Datenanalyse Cluster der Hochschulen (DACHS) is a parallel computer with distributed memory connected over Infiniband and Ethernet.
The compute nodes contain at least dual AMD processors, at least 384GB of local memory, 2 TB local NVMe-based disc storage and accelerators as shown in the table below.
With BeeGFS, a fast and scalable filesystem is provided via Infiniband to all both login and all compute nodes.

The Operating System is Rocky-Linux 9.5 (which is based on RHEL).
The setup is kept in-line (with regard to Software, Setup and general usage) and thus mostly equivalent to bwHPC and bwUniCluster in particular.

= Components of DACHS =

{| class="wikitable"
|-
! style="width:9%"|
! style="width:13%"| Compute nodes "L40S"
! style="width:13%"| Compute nodes "H100"
! style="width:13%"| Compute nodes "AMD_APU"
! style="width:13%"| Login
|-
!scope="column"| Availability in Queue
| <code>gpu1</code>
| <code>gpu8</code>
| <code>gpu4</code>
|
|-
!scope="column"| Number of nodes
| 45
| 1
| 1
| 2
|-
!scope="column"| Processors
| AMD EPYC 9254
| AMD EPYC 9454
| AMD MI300A
| AMD EPYC 9254
|-
!scope="column"| Number of sockets
| 2
| 2
| 4
| 2
|-
!scope="column"| Processor frequency (GHz)
| 2.9 Ghz
| 2.75 Ghz
| 2.1 Ghz
| 2.9 Ghz
|-
!scope="column"| Total number of cores
| 48
| 96
| 96
| 48
|-
!scope="column"| Main memory
| 384 GB
| 1536 GB
| 512 GB
| 384 GB
|-
!scope="column"| Local SSD
| 1,92 TB NVMe
| 1,92 TB NVMe
| 1,92 TB NVMe
| 1,92 TB NVMe
|-
!scope="column"| Accelerators
| 1x NVIDIA L40S
| 8x NVIDIA H100
| 4x AMD MI300A
| -
|-
!scope="column"| Accelerator memory
| 48 GB
| 8x 80 GB
| 4x 128 GB
| -
|-
!scope="column"| Interconnect
| IB HDR100
| IB HDR100
| IB HDR100
| IB HDR100
|}
Table 1: Properties of the nodes

== Storage Architecture ==
The system features a 700 TB large BeeGFS filesystem available on login and compute nodes.
Please note: there is a hard file size quota per partner organization and a soft quota per user on Your HOME.
Users will be notified by E-Mail if the quota is to be reached.

Please '''do make usage''' of [[Workspace | Work Space mechanism]] for larger files.

DACHS/Quickstart Slurm

2026-01-14T13:42:49Z

M Kunzelmann: add sacct command

= Quickstart =


== Contact and Further Links to bwHPC wiki ==

If you don't find the information you need in this wiki, you can always reach us at [mailto:dachs-admin@hs-esslingen.de dachs-admin@hs-esslingen.de].


== Typical SBATCH script ==

This is just a brief guide to get you started. All queues, limits, and hardware are documented in detail at the [[DACHS/Hardware]].

Our default queue is <code>gpu1</code> that you specify with <code>--partition=gpu1</code> explicitly. Other queues are <code>gpu4</code> (4 AMD MI300A APUs) and <code>gpu8</code> (8 NVIDIA H100 GPUs). For more deatiled information, visit [https://wiki.bwhpc.de/e/DACHS/Queues DACHS/Queues].

This is the content of <code>testjob.sh</code>. It is basically a Bash script with some instructions in the format of comment for the Slurm scheduler.

<syntaxhighlight lang="sh">#!/bin/bash
#SBATCH --ntasks=1 # allocate 1 CPU
#SBATCH --time=30:00 # time limit of 30 min
#SBATCH --mem=42gb # allocate 42 GB RAM
#SBATch --gres=gpu:1 # allocate one GPU
#SBATCH --job-name="CHANGEME JOBNAME"
# Uncomment the following lines to get email notifications about your job
# #SBATCH --mail-type=ALL # list of "ALL,START,END
# #SBATCH --mail-user=CHANGME@EMAIL.COM

# You Shell script that setups your job and starts your work is here.
# That might include loading a module from provided software (check with
# `module avail` or sourcing a Python environment.

# Load Python 3.13.3 compiled with gnu 14.2
module load devel/python/3.13.3-gnu-14.2

# Run your Python script that you previously prepared on the Login node.
uv run python3 main.py</syntaxhighlight>
For a detailed overview of slurm visit the [https://wiki.bwhpc.de/e/BwUniCluster2.0/Slurm SBATCH options and Slurm wiki page].

You can display available nodes by running

<syntaxhighlight lang="sh">sinfo_t_idle</syntaxhighlight>

Submit your job:
<syntaxhighlight lang="sh">sbatch testjob.sh</syntaxhighlight>

When you queued a job, you can show its status:

<syntaxhighlight lang="sh">squeue</syntaxhighlight>
If resources are not immediately available add <code>--start</code> to show its expected start time:

<syntaxhighlight lang="sh">squeue --start</syntaxhighlight>
If you want to cancel your job run

<syntaxhighlight lang="sh">scancel <jobid></syntaxhighlight>

Show all of your jobs started on the current day or since the specified starttime.

<syntaxhighlight lang="sh">sacct --format=User,JobID,Jobname%50,partition,state,start,end,elapsed,time,MaxRss,MaxVMSize,nnodes,ncpus,nodelist --starttime=2025-12-01</syntaxhighlight>

NEMO2/Workspaces

2026-01-12T15:47:20Z

M Kunzelmann: add DACHS to ws_restore list

<div style="border: 3px solid #ffc107; padding: 15px; background-color: #fff3cd; margin: 10px 0;">
'''Note:''' This is the updated Workspaces guide. The old wiki: [[Workspace]].
</div>

'''Workspace tools''' provide temporary storage spaces called '''workspaces''' for your calculations. They are meant for data that needs to persist longer than a single job, but not permanently.

== What are Workspaces? ==

Workspaces give you access to the cluster's fast parallel filesystems (like Lustre or Weka). '''You cannot write directly to these parallel filesystems''' - workspaces provide your designated area.

'''Use workspaces for:'''
* Jobs generating intermediate data
* Data shared between multiple compute nodes
* Multi-step workflows
* Temporary scratch space during calculations

'''Don't use workspaces for:'''
* Permanent storage (use HOME or project directories)
* Single-node temporary files (use <tt>$TMPDIR</tt> instead)

== Important - Read First ==

* '''No Backup:''' Data is '''not backed up''' and will be '''automatically deleted''' after expiration
* '''Time-limited:''' Lifetime typically 30-100 days (cluster-specific). See [[Workspaces/Advanced_Features/Quotas#Cluster-Specific_Workspace_Limits|Cluster Limits]]
* '''Automatic Reminders:''' Email notifications before expiration
* '''Backup Important Data:''' Copy results to permanent storage before expiration

'''For advanced features and detailed options:''' [[Workspaces/Advanced Features]]

== Command Overview ==

Main commands:

* <tt>ws_allocate</tt> - Create or extend workspace
* <tt>ws_list</tt> - List your workspaces
* <tt>ws_find</tt> - Find workspace path (for scripts)
* <tt>ws_extend</tt> - Extend workspace lifetime
* <tt>ws_release</tt> - Release (delete) workspace
* <tt>ws_restore</tt> - Restore expired/released workspace
* <tt>ws_register</tt> - Create symbolic links

All commands support <tt>-h</tt> for help.

== Quick Start ==

{| class="wikitable"
|-
!style="width:40%" | Task
!style="width:60%" | Command
|-
|Create workspace (30 days)
|<tt>ws_allocate myWs 30</tt>
|-
|Create group workspace
|<tt>ws_allocate -G groupname myWs 30</tt>
|-
|List all workspaces
|<tt>ws_list</tt>
|-
|See what expires soon
|<tt>ws_list -Rr</tt> (<tt>-R</tt>=by time, <tt>-r</tt>=reverse)
|-
|Find path (for scripts)
|<tt>ws_find myWs</tt>
|-
|Extend by 30 days
|<tt>ws_extend myWs 30</tt>
|-
|Delete workspace
|<tt>ws_release myWs</tt>
|-
|Restore workspace
|<tt>ws_restore -l</tt> then <tt>ws_restore oldname newname</tt>
|}

== Create Workspace ==

Create a workspace with a '''name''' and '''lifetime''' in days:

$ ws_allocate myWs 30 # Create for 30 days

Returns:

Workspace created. Duration is 720 hours.
Further extensions available: 3
/work/workspace/scratch/username-myWs-0

'''Common options:'''

$ ws_allocate -G groupname myWs 30 # Group-writable (for teams)
$ ws_allocate -g myWs 30 # Group-readable
$ ws_allocate -F ffuc myWs 30 # bwUniCluster 3.0: Flash filesystem

'''Capture path in variable:'''

$ WORKSPACE=$(ws_allocate myWs 30)
$ cd "$WORKSPACE"

'''Important:''' Running the same command again is safe - returns the existing workspace path.

'''Details:''' [[Workspaces/Advanced_Features/ws_allocate|Advanced Features guide]]

== List Your Workspaces ==

$ ws_list # List all workspaces

Shows workspace ID, location, extensions, creation date, and remaining time.

'''Common options:'''

$ ws_list -Rr # Sort by remaining time, reverse (last to expire first)
$ ws_list -s # Short format (names only, for scripts)
$ ws_list -g # Show group workspaces

'''Note:''' To list expired workspaces for restore, use <tt>ws_restore -l</tt>. See [[#Restore_Workspace|Restore]].

'''Details:''' [[Workspaces/Advanced_Features/ws_list|Advanced Features guide]]

== Extend Workspace Lifetime ==

Extend before workspace expires:

$ ws_extend myWs 30 # Extend by 30 days from now

'''Alternative:'''

$ ws_allocate -x myWs 30 # Same result

'''Note:''' Each extension consumes one available extension. See [[Workspaces/Advanced_Features/Quotas#Cluster-Specific_Workspace_Limits|Cluster Limits]].

'''Group workspaces:''' See [[#Extend_Group_Workspace|Extend Group Workspace]] for extending workspaces created by colleagues.

'''Details:''' [[Workspaces/Advanced_Features/ws_extend|Advanced Features guide]]

== Release (Delete) Workspace ==

When no longer needed:

$ ws_release myWs # Release workspace

'''What happens:'''
* Workspace becomes inaccessible immediately
* Data kept for short grace period (typically until next cleanup)
* Can be restored with <tt>ws_restore</tt> during grace period
* May still count toward quota until final deletion

'''Details:''' [[Workspaces/Advanced_Features/ws_release|Advanced Features guide]]

== Restore Workspace ==

{| class="wikitable"
|-
!style="width:40%" | Works on cluster
!style="width:10%" | bwUC 3.0
!style="width:10%" | BinAC2
!style="width:10%" | Helix
!style="width:10%" | JUSTUS 2
!style="width:10%" | NEMO2
!style="width:10%" | DACHS
|-
|<tt>ws_restore</tt>
|style="background-color:#90EE90; text-align:center;" | ✓
|style="background-color:#90EE90; text-align:center;" | ✓
|style="background-color:#90EE90; text-align:center;" | ✓
|style="background-color:#90EE90; text-align:center;" | ✓
|style="background-color:#90EE90; text-align:center;" | ✓
|style="background-color:#90EE90; text-align:center;" | ✓
|}

Recover expired or released workspaces within grace period:

'''Restore procedure:'''

$ ws_restore -l # (1) List restorable workspaces
$ ws_allocate restored 60 # (2) Create target workspace
$ ws_restore username-myWs-0 restored # (3) Restore

'''Important:''' Use the '''full name''' from <tt>ws_restore -l</tt> (with username and timestamp), not the short name.

'''Details:''' [[Workspaces/Advanced_Features/ws_restore|Advanced Features guide]]

== Work with Groups (Share Workspaces) ==

{| class="wikitable"
|-
!style="width:40%" | Works on cluster
!style="width:10%" | bwUC 3.0
!style="width:10%" | BinAC2
!style="width:10%" | Helix
!style="width:10%" | JUSTUS 2
!style="width:10%" | NEMO2
|-
|<tt>-g</tt> (group-readable)
| style="text-align:center;" |
| style="text-align:center;" |
| style="text-align:center;" |
| style="text-align:center;" |
|style="background-color:#90EE90; text-align:center;" | ✓
|-
|<tt>-G</tt> (group-writable)
| style="text-align:center;" |
| style="text-align:center;" |
| style="text-align:center;" |
| style="text-align:center;" |
|style="background-color:#90EE90; text-align:center;" | ✓
|}

Simple team collaboration with group workspaces:

=== Create Group Workspace ===

'''Group-readable (read-only):'''

$ ws_allocate -g myWs 30

'''Group-writable (recommended):'''

$ ws_allocate -G projectgroup myWs 30 # Replace 'projectgroup' with your group

'''Tip:''' Set default in <tt>~/.ws_user.conf</tt>:

<pre>
groupname: projectgroup
</pre>

Then simply: <tt>ws_allocate myWs 30</tt>

=== List Group Workspaces ===

$ ws_list -g # Show all group workspaces

=== Extend Group Workspace ===

Anyone in the group can extend group-writable workspaces (<tt>-G</tt>):

$ ws_extend myWs 30 # If you created it
$ ws_allocate -x -u alice myWs 30 # If colleague created it

=== Manage Reminders ===

Take over reminder responsibility:

$ ws_allocate -r 7 -u alice -x myWs 0 # Update timing and take over reminders

Changes reminder to 7 days before expiration and redirects emails to you.

=== Why Use Group Workspaces? ===

* Simple collaboration - everyone accesses same data
* No permission problems - automatic group permissions
* Independent extensions - team can extend without creator
* Easy discovery - <tt>ws_list -g</tt> shows all team workspaces

'''Advanced sharing:''' [[Workspaces/Advanced_Features/Sharing|Sharing guide]] for ACLs and ws_share

DACHS/Software

2025-11-25T08:22:52Z

M Kunzelmann:

For available Software Modules, please [[DACHS/Login|login via SSH]] described above and type <code>module avail</code>.

== Halcon ==

Halcon 24.11 is available on DACHS for users of HS Esslingen.

module help cs/halcon/24.11

TODO: configure license.

DACHS/Software

2025-11-25T08:20:11Z

M Kunzelmann:

For available Software Modules, please [[DACHS/Login|login via SSH]] described above and type <code>module avail</code>.

== Halcon ==

Halcon 24.11 is available on DACHS for users of HS Esslingen.

<syntaxhighlight>
module help cs/halcon/24.11
</syntaxhighlight>

TODO: configure license.

2024-12-19T15:35:21Z

M Kunzelmann: Adjust DNS login host selection

{|style="background:#deffee; width:100%;"
|style="padding:5px; background:#cef2e0; text-align:left"|
[[Image:Attention.svg|center|25px]]
|style="padding:5px; background:#cef2e0; text-align:left"|
Access to DACHS is '''limited to IP addresses from the BelWü network'''.
All home institutions of our current users are connected to BelWü, so if you are on your campus network (e.g. in your office or on the Campus WiFi) you should be able to connect to DACHS without restrictions.
If you are outside one of the BelWü networks (e.g. at home), a VPN connection to the home institution or a connection to an SSH jump host at the home institution must be established first.
|}

The login nodes of the DACHS cluster are the access points to the compute system, your <code>$HOME</code> directory and your workspaces.
All users must log in through these nodes to submit jobs to the cluster.

'''Prerequisites for successful login:'''

You need to have
* completed the 3-step [[registration]] procedure.
* [[Registration/Password|set a service password]] for DACHS.
* [[Registration/2FA|set up a second factor]] for the time-based one-time password (TOTP).

= Login to the DACHS =

Login to the DACHS is only possible with a Secure Shell (SSH) client for which you must know your username on the cluster and the hostname of the login nodes.
For more general information on SSH clients, visit the [[Registration/Login/Client|SSH clients Guide]].

== Username ==

If you want to use DACHS, you need to add a prefix to your local username: <code>prefix_username</code>.

{| class="wikitable"
! University !! Prefix
|-
| HS Aalen || aa
|-
| HS Albstadt-Sigmaringen || as
|-
| HS Esslingen || es
|-
| HS Heilbronn || hn
|-
| HS Karlsruhe || hk
|-
| HTWG Konstanz || ht
|-
| HS Mannheim || mn
|-
| HS Offenburg || of
|-
| HS Reutlingen || hr
|-
| HfT-Stuttgart || hs
|-
| THU-Ulm || hu
|-
|}

For a full list of user names, you can check the [https://www.bwidm.de/hochschulen.php bwIDM Hochschulen page].

'''Example:''' 
If your local username for the University is <code>vwxyz1234</code> and you are a user from the University of Esslingen this would combine to: <code>es_vwxyz1234</code>.

== Hostnames ==

The system has two 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.

Login to DACHS:

{| class="wikitable"
! Hostname !! Node type
|-
| '''dachs-login.hs-esslingen.de''' || login to one of the two login nodes
|-
|}

In general, you should use automatic selection to allow us to balance the load over the two login nodes.
If you need to connect to specific login node, you can use the following hostnames:

{| class="wikitable"
! Hostname !! Node type
|-
| '''dachs-login1.hs-esslingen.de''' || DACHS first login node
|-
| '''dachs-login2.hs-esslingen.de''' || DACHS second login node
|-
|}

If you explicitly connect to dachs-login1 but wind up on dachs-login2 (or the other way around), then of of them might not be available at the time and you're automatically redirected to the other one.

== Host Keys ==

When you log in, you may receive the message <code>The authenticity of host '<host address>' can't be established.</code> along with the host key fingerprint. This is intended so you can verify the authenticity of the host you are connecting to. Before you continue you should verify, if this fingerprint matches one of the following:

{| class="wikitable"
! Algorithm !! Fingerprint (SHA256)
|-
| '''RSA''' || SHA256:kdvbATXbd/ggG33G7VEw+O+FpJPcZU6XDeFyWXvBkhc
|-
| '''ECDSA''' || SHA256:4Y/LvkPL9g9DZ8JrmTxXsMTIWyM/u/mEEmSB7S/2yyA
|-
| '''ED25519''' || SHA256:X9eRJepYD3da3BM1pgiWxnvRc/Pt5eBLUr18tDUsZjU
|-
|}

== Login with SSH command (Linux, Mac, Windows) ==

Most Unix and Unix-like operating systems like Linux, Mac OS and *BSD come with a built-in SSH client provided by the OpenSSH project.
More recent versions of Windows 10 and Windows 11 using the [https://docs.microsoft.com/en-us/windows/wsl/install Windows Subsystem for Linux] (WSL) also come with a built-in OpenSSH client.

For login use one of the following ssh commands:

ssh <username>@dachs-login.hs-esslingen.de
ssh -l <username> dachs-login.hs-esslingen.de

To run graphical applications, you can use the <code>-X</code> or <code>-Y</code> flag to <code>ssh</code>:

ssh -Y -l <username> dachs-login.hs-esslingen.de

For better performance, we recommend using [[VNC]].

== Login with graphical SSH client (Windows) ==

For Windows we suggest using MobaXterm for login and file transfer.

Start ''MobaXterm'', fill in the following fields:
<pre>
Remote name : dachs-login.hs-esslingen.de
Specify user name : <username>
Port : 22
</pre>

After that click on 'ok'. Then a terminal will be opened and there you can enter your credentials.

'''Note:''' When using File transfer with MobaXterm version 23.6 the following configuration change has to be made:
In the settings in the tab "SSH", change the option "SSH engine" from "<new>" to "<legacy>". Then restart MobaXterm



== Login Example ==

To log in to DACHS, you must provide your [[Registration/Password|service password]].
Proceed as follows:
# Use SSH for a login node.
# The system will ask for a one-time password <code>Your OTP:</code>. Please enter your OTP and confirm it with Enter/Return. If you do not have a second factor yet, please create one (see [[Registration/2FA]]).
# The system will ask you for your service password <code>Password:</code>. Please enter it and confirm it with Enter/Return. If you do not have a service password yet or have forgotten it, please create one (see [[Registration/Password]]).
# You will be greeted by the DACHS cluster, followed by a shell.

<pre>
~ $ ssh -l es_vwxyz1234 dachs-login.hs-esslingen.de
(es_vwxyz1234@dachs-login.hs-esslingen.de) Your OTP: 123456
(es_vwxyz1234@dachs-login.hs-esslingen.de) Password:
********************************************************************************
Last login: Thu Jul 7 18:09:43 2022 from dachs-login.hs-esslingen.de
********************************************************************************
[es_vwxyz1234@login1 ~]$
</pre>

== Troubleshooting ==

Nothing yet.



= Allowed Activities on Login Nodes =

{|style="background:#deffee; width:100%;"
|style="padding:5px; background:#cef2e0; text-align:left"|
[[Image:Attention.svg|center|25px]]
|style="padding:5px; background:#cef2e0; text-align:left"|
To guarantee usability for all the users of clusters you must not run your compute jobs on the login nodes.
Compute jobs must be submitted to the queuing system.
Any compute job running on the login nodes will be terminated without any notice.
Any long-running compilation or any long-running pre- or post-processing of batch jobs must also be submitted to the queuing system.
|}

The login nodes of the DACHS cluster are the access point to the compute system, your <code>$HOME</code> directory and your workspaces.
These nodes are shared with all the users therefore, your activities on the login nodes are limited to primarily set up your batch jobs.
Your activities may also be:
* '''short''' compilation of your program code and
* '''short''' pre- and post-processing of your batch jobs.



We advise users to use [[DACHS/Queues|interactive jobs]] for compute and memory intensive tasks like compiling.

= Related Information =

* If you want to reset your service password, consult the [[Registration/Password|Password Guide]].
* If you want to register a new token for the two factor authentication (2FA), consult the [[Registration/2FA|2FA Guide]].
* If you want to de-register, consult the [[Registration/Deregistration|De-registration Guide]].
* If you need an SSH key for your workflow, read [[Registration/SSH|Registering SSH Keys with your Cluster]].
* Configuring your shell: [[.bashrc Do's and Don'ts]]

DACHS/Login

2024-12-19T15:23:12Z

M Kunzelmann: Set host keys

{|style="background:#deffee; width:100%;"
|style="padding:5px; background:#cef2e0; text-align:left"|
[[Image:Attention.svg|center|25px]]
|style="padding:5px; background:#cef2e0; text-align:left"|
Access to DACHS is '''limited to IP addresses from the BelWü network'''.
All home institutions of our current users are connected to BelWü, so if you are on your campus network (e.g. in your office or on the Campus WiFi) you should be able to connect to DACHS without restrictions.
If you are outside one of the BelWü networks (e.g. at home), a VPN connection to the home institution or a connection to an SSH jump host at the home institution must be established first.
|}

The login nodes of the DACHS cluster are the access points to the compute system, your <code>$HOME</code> directory and your workspaces.
All users must log in through these nodes to submit jobs to the cluster.

'''Prerequisites for successful login:'''

You need to have
* completed the 3-step [[registration]] procedure.
* [[Registration/Password|set a service password]] for DACHS.
* [[Registration/2FA|set up a second factor]] for the time-based one-time password (TOTP).

= Login to the DACHS =

Login to the DACHS is only possible with a Secure Shell (SSH) client for which you must know your username on the cluster and the hostname of the login nodes.
For more general information on SSH clients, visit the [[Registration/Login/Client|SSH clients Guide]].

== Username ==

If you want to use DACHS, you need to add a prefix to your local username: <code>prefix_username</code>.

{| class="wikitable"
! University !! Prefix
|-
| HS Aalen || aa
|-
| HS Albstadt-Sigmaringen || as
|-
| HS Esslingen || es
|-
| HS Heilbronn || hn
|-
| HS Karlsruhe || hk
|-
| HTWG Konstanz || ht
|-
| HS Mannheim || mn
|-
| HS Offenburg || of
|-
| HS Reutlingen || hr
|-
| HfT-Stuttgart || hs
|-
| THU-Ulm || hu
|-
|}

For a full list of user names, you can check the [https://www.bwidm.de/hochschulen.php bwIDM Hochschulen page].

'''Example:''' 
If your local username for the University is <code>vwxyz1234</code> and you are a user from the University of Esslingen this would combine to: <code>es_vwxyz1234</code>.

== Hostnames ==

The system has two login nodes.
The selection of the login node is done automatically. (TODO. Needs to be implemented by RZ.)
If you are logging in multiple times, different sessions might run on different login nodes.

Login to DACHS:

{| class="wikitable"
! Hostname !! Node type
|-
| '''dachs-login.hs-esslingen.de''' || login to one of the two login nodes
|-
|}

In general, you should use automatic selection to allow us to balance the load over the two login nodes.
If you need to connect to specific login nodes, you can use the following hostnames:

{| class="wikitable"
! Hostname !! Node type
|-
| '''dachs-login1.hs-esslingen.de''' || DACHS first login node
|-
| '''dachs-login2.hs-esslingen.de''' || DACHS second login node
|-
|}

== Host Keys ==

When you log in, you may receive the message <code>The authenticity of host '<host address>' can't be established.</code> along with the host key fingerprint. This is intended so you can verify the authenticity of the host you are connecting to. Before you continue you should verify, if this fingerprint matches one of the following:

{| class="wikitable"
! Algorithm !! Fingerprint (SHA256)
|-
| '''RSA''' || SHA256:kdvbATXbd/ggG33G7VEw+O+FpJPcZU6XDeFyWXvBkhc
|-
| '''ECDSA''' || SHA256:4Y/LvkPL9g9DZ8JrmTxXsMTIWyM/u/mEEmSB7S/2yyA
|-
| '''ED25519''' || SHA256:X9eRJepYD3da3BM1pgiWxnvRc/Pt5eBLUr18tDUsZjU
|-
|}

== Login with SSH command (Linux, Mac, Windows) ==

Most Unix and Unix-like operating systems like Linux, Mac OS and *BSD come with a built-in SSH client provided by the OpenSSH project.
More recent versions of Windows 10 and Windows 11 using the [https://docs.microsoft.com/en-us/windows/wsl/install Windows Subsystem for Linux] (WSL) also come with a built-in OpenSSH client.

For login use one of the following ssh commands:

ssh <username>@dachs-login.hs-esslingen.de
ssh -l <username> dachs-login.hs-esslingen.de

To run graphical applications, you can use the <code>-X</code> or <code>-Y</code> flag to <code>ssh</code>:

ssh -Y -l <username> dachs-login.hs-esslingen.de

For better performance, we recommend using [[VNC]].

== Login with graphical SSH client (Windows) ==

For Windows we suggest using MobaXterm for login and file transfer.

Start ''MobaXterm'', fill in the following fields:
<pre>
Remote name : dachs-login.hs-esslingen.de
Specify user name : <username>
Port : 22
</pre>

After that click on 'ok'. Then a terminal will be opened and there you can enter your credentials.

'''Note:''' When using File transfer with MobaXterm version 23.6 the following configuration change has to be made:
In the settings in the tab "SSH", change the option "SSH engine" from "<new>" to "<legacy>". Then restart MobaXterm



== Login Example ==

To log in to DACHS, you must provide your [[Registration/Password|service password]].
Proceed as follows:
# Use SSH for a login node.
# The system will ask for a one-time password <code>Your OTP:</code>. Please enter your OTP and confirm it with Enter/Return. If you do not have a second factor yet, please create one (see [[Registration/2FA]]).
# The system will ask you for your service password <code>Password:</code>. Please enter it and confirm it with Enter/Return. If you do not have a service password yet or have forgotten it, please create one (see [[Registration/Password]]).
# You will be greeted by the DACHS cluster, followed by a shell.

<pre>
~ $ ssh -l es_vwxyz1234 dachs-login.hs-esslingen.de
(es_vwxyz1234@dachs-login.hs-esslingen.de) Your OTP: 123456
(es_vwxyz1234@dachs-login.hs-esslingen.de) Password:
********************************************************************************
Last login: Thu Jul 7 18:09:43 2022 from dachs-login.hs-esslingen.de
********************************************************************************
[es_vwxyz1234@login1 ~]$
</pre>

== Troubleshooting ==

Nothing yet.



= Allowed Activities on Login Nodes =

{|style="background:#deffee; width:100%;"
|style="padding:5px; background:#cef2e0; text-align:left"|
[[Image:Attention.svg|center|25px]]
|style="padding:5px; background:#cef2e0; text-align:left"|
To guarantee usability for all the users of clusters you must not run your compute jobs on the login nodes.
Compute jobs must be submitted to the queuing system.
Any compute job running on the login nodes will be terminated without any notice.
Any long-running compilation or any long-running pre- or post-processing of batch jobs must also be submitted to the queuing system.
|}

The login nodes of the DACHS cluster are the access point to the compute system, your <code>$HOME</code> directory and your workspaces.
These nodes are shared with all the users therefore, your activities on the login nodes are limited to primarily set up your batch jobs.
Your activities may also be:
* '''short''' compilation of your program code and
* '''short''' pre- and post-processing of your batch jobs.



We advise users to use [[DACHS/Queues|interactive jobs]] for compute and memory intensive tasks like compiling.

= Related Information =

* If you want to reset your service password, consult the [[Registration/Password|Password Guide]].
* If you want to register a new token for the two factor authentication (2FA), consult the [[Registration/2FA|2FA Guide]].
* If you want to de-register, consult the [[Registration/Deregistration|De-registration Guide]].
* If you need an SSH key for your workflow, read [[Registration/SSH|Registering SSH Keys with your Cluster]].
* Configuring your shell: [[.bashrc Do's and Don'ts]]