Review

* Apply rules w.r.t. prompts and code blocks
* Restructure sections

doc.zih.tu-dresden.de/docs/access/ssh_login.md

-# Login to the High Performance Computers
-
-The best way to login to the HPC systems is via ssh. <br></br>
-From a Linux console, the command syntax is: `ssh user@host`. <br></br>
-The additional option `-XC` enables X11 forwarding for graphical applications <br></br>
-(the `-C` enables compression which usually improves usability in this case).
-
-The following table gives an overview of all clusters.
-
-**Attention:** <br></br>
-For security reasons, this port is only accessible for hosts within the domains of <br></br>
-TU Dresden. Guests from other research institutes can use the 
-[VPN](https://tu-dresden.de/zih/dienste/service-katalog/arbeitsumgebung/zugang_datennetz/vpn)
-gateway of the ZIH. <br></br> 
-Information on these topics can be found on our web pages <http://www.tu-dresden.de/zih>.
-
-## SSH Access
-### SSH Key
-All public ssh keys for Taurus have to be generated with the following attributes:
-  * the **ED25519** algorithm has to be used <br></br>
-    (command: `ssh-keygen -t ed25519`)
-  * a passphrase for the private key must be set (**<ins>not empty!</ins>** )
-
-### Access from a Windows workstation
-
-To access HPC systems from a windows workstation we suggest one of <br></br>
-the following applications:
-  * MobaXTerm \[[homepage](https://mobaxterm.mobatek.net) | [Tutorial](../misc/Basic usage of MobaXterm.pdf)\]
-  * PuTTY \[[homepage](https://www.putty.org) | [Tutorial](../misc/Basic usage of PuTTY.pdf)\]
-  * OpenSSH Server [docs](https://docs.microsoft.com/de-de/windows-server/administration/openssh/openssh_install_firstuse)
-
-**Note:** <br></br>
-Some applications need get X-forwarding enabled before they support specific software <br></br>
-from our [modules system](../software/modules.md/).
-
-### Access from a Linux Workstation
-
-**Attention:** <br></br>
- Please use an up-to-date SSH client. The login nodes accept the following encryption
-algorithms: <br></br>
-  * `aes128-ctr`
-  * `aes192-ctr`
-  * `aes256-ctr`
-  * `aes128-gcm@openssh.com`
-  * `aes256-gcm@openssh.com`
-  * `chacha20-poly1305@openssh.com`
-  * `chacha20-poly1305@openssh.com`
-
-### SSH session
-
-If your workstation is within the campus network, you can connect to the
-HPC login servers directly (Port 22), e.g., for Taurus:
-
-```Bash
-# without ssh-key
-ssh <zih-login>@taurus.hrsk.tu-dresden.de
-
-# with ssh-key
-ssh -i id-ed25519 <zih-login>@taurus.hrsk.tu-dresden.de
+# Connecting with SSH
+
+For security reasons, ZIH systems are only accessible for hosts within the domains of TU Dresden.
+
+## Virtual Private Network (VPN)
+
+To access HPC systems from outside the campus networks it's recommended to set up a VPN connection to
+enter the campus network. While active it allows the user to connect directly to the HPC login
+nodes.
+
+For more information on our VPN and how to set it up, please visit the corresponding
+[ZIH service catalogue page](https://tu-dresden.de/zih/dienste/service-katalog/arbeitsumgebung/zugang_datennetz/vpn).
+
+## Connecting from Linux
+
+Please use an up-to-date SSH client. The login nodes accept the following encryption algorithms:
+
+* `aes128-ctr`
+* `aes192-ctr`
+* `aes256-ctr`
+* `aes128-gcm@openssh.com`
+* `aes256-gcm@openssh.com`
+* `chacha20-poly1305@openssh.com`
+* `chacha20-poly1305@openssh.com`
+
+### SSH Session
+
+If your workstation is within the campus network, you can connect to the HPC login nodes directly.
+
+```console
+marie@local$ ssh <zih-login>@taurus.hrsk.tu-dresden.de
 ```
 
-If you connect for the fist time, the client will ask you to verify the host by the fingerprint:
+If you connect for the fist time, the client will ask you to verify the host by its fingerprint:
 
-```Bash
-localhost$: ssh <zih-login>@taurus.hrsk.tu-dresden.de
+```console
+marie@local$: ssh <zih-login>@taurus.hrsk.tu-dresden.de
 The authenticity of host 'taurus.hrsk.tu-dresden.de (141.30.73.104)' can't be established.
 RSA key fingerprint is SHA256:HjpVeymTpk0rqoc8Yvyc8d9KXQ/p2K0R8TJ27aFnIL8.
 Are you sure you want to continue connecting (yes/no)?
 ```
 
-Compare this fingerprint with the fingerprints in the table below. If
-they match you can type "yes".
-
-| Host                      | Fingerprint           |
-|:--------------------------|:----------------------|
-| tauruslogin3.hrsk.tu-dresden.de | SHA256:/M1lW1KTOlxj8UFZJS4tLi+8TyndcDqrZfLGX7KAU8s (RSA)      |
-| tauruslogin4.hrsk.tu-dresden.de | SHA256:PeCpW/gAFLvHDzTP2Rb93NxD+rpUsyQY8WebjQC7kz0 (ECDSA)    |
-| tauruslogin5.hrsk.tu-dresden.de | SHA256:nNxjtCny1kB0N0epHaOPeY1YFd0ri2Dvt2CK7rOGlXg (ED25519)  |
-| tauruslogin6.hrsk.tu-dresden.de | or: MD5:b8:e1:21:ed:38:1a:ba:1a:5b:2b:bc:35:31:62:21:49 (RSA) |
-| taurus.hrsk.tu-dresden.de       | MD5:47:7e:24:46:ab:30:59:2c:1f:e8:fd:37:2a:5d:ee:25 (ECDSA)   |
-|                                 | MD5:7c:0c:2b:8b:83:21:b2:08:19:93:6d:03:80:76:8a:7b (ED25519) |
-| taurusexport.hrsk.tu-dresden.de  | SHA256:Qjg79R+5x8jlyHhLBZYht599vRk+SujnG1yT1l2dYUM (RSA)   |
-| taurusexport3.hrsk.tu-dresden.de | SHA256:qXTZnZMvdqTs3LziA12T1wkhNcFqTHe59fbbU67Qw3g (ECDSA) |
-| taurusexport4.hrsk.tu-dresden.de | SHA256:jxWiddvDe0E6kpH55PHKF0AaBg/dQLefQaQZ2P4mb3o (ED25519)  |
-|                                  | or: MD5:1e:4c:2d:81:ee:58:1b:d1:3c:0a:18:c4:f7:0b:23:20 (RSA) |
-|                                  | MD5:96:62:c6:80:a8:1f:34:64:86:f3:cf:c5:9b:cd:af:da (ECDSA)   |
-|                                  | MD5:fe:0a:d2:46:10:4a:08:40:fd:e1:99:b7:f2:06:4f:bc (ED25519) |
-
-### VPN (Virtual Private Network)
-To access HPC systems from outside the campus networks its recommended to set up <br></br>
-a VPN connection to enter the campus network. <br></br>
-While active it allows the user to connect directly to the HPC login servers.
+Compare the shown fingerprint with the [documented fingerprints](key_fingerprints.md). Make sure
+they match. Than you can accept by typing `y` or `yes`.
 
-For more information on our VPN and how to set it up, please visit the corresponding
-[ZIH service catalogue page](https://tu-dresden.de/zih/dienste/service-katalog/arbeitsumgebung/zugang_datennetz/vpn).
+### X11-Forwarding
+
+If you plan to use an application with graphical user interface (GUI), you need to enable
+X11-forwarding for the connection. Add the option `-X` or `-XC` to your SSH command. The `-C` enables
+compression which usually improves usability in this case).
+
+```console
+marie@local$ ssh -XC <zih-login>@taurus.hrsk.tu-dresden.de
+```
+
+!!! info
+
+    Also consider to use a [DCV session](desktop_cloud_visualization.md) for remote desktop
+    visualization at ZIH systems.
+
+### Password-less SSH
+
+Of course, password-less SSH connecting is supported at ZIH. All public SSH keys for ZIH systems
+have to be generated following these rules:
+
+  * The **ED25519** algorithm has to be used, e.g., `ssh-keygen -t ed25519`
+  * A **non-empty** passphrase for the private key must be set.
+
+The generated public key is usually saved at `~/.ssh/id_ed25519` at your local system. To allow for
+password-less SSH connection to ZIH systems, it has to be added to the file `.ssh/authorized_keys` within
+your home directory `/home/<zih-login>/` at ZIH systems.
+
+```console
+marie@local$ ssh -i id-ed25519 <zih-login>@taurus.hrsk.tu-dresden.de
+Enter passphrase for key 'id-ed25519':
+```
+
+## Connecting from Windows
 
-### Access using JupyterHub
+We recommend one of the following applications:
 
-A JupyterHub installation offering IPython Notebook is available under: <br></br>
-https://taurus.hrsk.tu-dresden.de/jupyter
+  * MobaXTerm: [homepage](https://mobaxterm.mobatek.net) | [ZIH Tutorial](misc/basic_usage_of_MobaXterm.pdf)
+  * PuTTY: [homepage](https://www.putty.org) | [ZIH Tutorial](misc/basic_usage_of_PuTTY.pdf)
+  * OpenSSH Server: [docs](https://docs.microsoft.com/de-de/windows-server/administration/openssh/openssh_install_firstuse)
 
-See the documentation under [JupyterHub](../access/jupyterhub.md).
+The page [key fingerprints](key_fingerprints.md) holds the up-to-date fingerprints for the login
+nodes. Make sure they match.

doc.zih.tu-dresden.de/docs/jobs_and_resources/system_taurus.md

@@ -23,7 +23,7 @@ Please note that if you store data on the local disk (e.g. under /tmp),
 it will be on only one of the three nodes. If you relogin and the data
 is not there, you are probably on another node.
 
-You can find an list of fingerprints [here](../access/login.md#SSH_access).
+You can find an list of fingerprints [here](../access/key_fingerprints.md).
 
 ## Transferring Data from/to Taurus
 
@@ -46,8 +46,6 @@ contact the Service Desk as well.
 **Phase 2:** The nodes taurusexport\[3,4\] provide access to the
 `/scratch` file system of the second phase.
 
-You can find an list of fingerprints [here](../access/login.md#SSH_access).
-
 ## Compiling Parallel Applications
 
 You have to explicitly load a compiler module and an MPI module on

doc.zih.tu-dresden.de/docs/software/big_data_frameworks.md

@@ -16,7 +16,7 @@ marie@login$ module av Spark
 The **aim** of this page is to introduce users on how to start working with
 these frameworks on ZIH systems, e. g. on the [HPC-DA](../jobs_and_resources/hpcda.md) system.
 
-**Prerequisites:** To work with the frameworks, you need [access](../access/login.md) to ZIH
+**Prerequisites:** To work with the frameworks, you need [access](../access/ssh_login.md) to ZIH
 systems and basic knowledge about data analysis and the batch system
 [Slurm](../jobs_and_resources/slurm.md).
 

doc.zih.tu-dresden.de/docs/software/deep_learning.md

 # Deep learning
 
-**Prerequisites**: To work with Deep Learning tools you obviously need [Login](../access/login.md)
+**Prerequisites**: To work with Deep Learning tools you obviously need [Login](../access/ssh_login.md)
 for the Taurus system and basic knowledge about Python, SLURM manager.
 
 **Aim** of this page is to introduce users on how to start working with Deep learning software on

doc.zih.tu-dresden.de/docs/software/get_started_with_hpcda.md

@@ -9,7 +9,7 @@ and tasks connected with the big data.
 The main **aim** of this guide is to help users who have started working with Taurus and focused on
 working with Machine learning frameworks such as TensorFlow or Pytorch.
 
-**Prerequisites:** To work with HPC-DA, you need [Login](../access/login.md) for the Taurus system
+**Prerequisites:** To work with HPC-DA, you need [Login](../access/ssh_login.md) for the Taurus system
 and preferably have basic knowledge about High-Performance computers and Python.
 
 **Disclaimer:** This guide provides the main steps on the way of using Taurus, for details please
@@ -59,7 +59,7 @@ during the access procedure. Accept the host verifying and enter your password.
 
 This method requires two conditions:
 Linux OS, workstation within the campus network. For other options and
-details check the [login page](../access/login.md).
+details check the [login page](../access/ssh_login.md).
 
 ## Data management
 

doc.zih.tu-dresden.de/docs/software/keras.md

@@ -29,7 +29,7 @@ options:
     Keras and GPUs.
 
 **Prerequisites**: To work with Keras you, first of all, need
-[access](../access/login.md) for the Taurus system, loaded
+[access](../access/ssh_login.md) for the Taurus system, loaded
 Tensorflow module on ml partition, activated Python virtual environment.
 Basic knowledge about Python, SLURM system also required.
 

doc.zih.tu-dresden.de/docs/software/python.md

@@ -6,7 +6,7 @@ effective. Taurus allows working with a lot of available packages and
 libraries which give more useful functionalities and allow use all
 features of Python and to avoid minuses.
 
-**Prerequisites:** To work with PyTorch you obviously need [access](../access/login.md) for the
+**Prerequisites:** To work with PyTorch you obviously need [access](../access/ssh_login.md) for the
 Taurus system and basic knowledge about Python, Numpy and SLURM system.
 
 **Aim** of this page is to introduce users on how to start working with Python on the

doc.zih.tu-dresden.de/docs/software/pytorch.md

@@ -8,7 +8,7 @@ PyTorch provides a core datastructure, the tensor, a multi-dimensional array tha
 similarities with Numpy arrays.
 PyTorch also consumed Caffe2 for its backend and added support of ONNX.
 
-**Prerequisites:** To work with PyTorch you obviously need [access](../access/login.md) for the
+**Prerequisites:** To work with PyTorch you obviously need [access](../access/ssh_login.md) for the
 Taurus system and basic knowledge about Python, Numpy and SLURM system.
 
 **Aim** of this page is to introduce users on how to start working with PyTorch on the

doc.zih.tu-dresden.de/docs/software/scs5_software.md

@@ -16,7 +16,7 @@ Here are the major changes from the user's perspective:
 Due to the new operating system, the host keys of the login nodes have also changed. If you have
 logged into tauruslogin6 before and still have the old one saved in your `known_hosts` file, just
 remove it and accept the new one after comparing its fingerprint with those listed under
-[Login](../access/login.md#ssh-access).
+[Login](../access/key_fingerprints.md).
 
 ## Using Software Modules
 

doc.zih.tu-dresden.de/docs/software/tensorflow.md

@@ -19,7 +19,7 @@ community resources. It is available on taurus along with other common machine
 learning packages like Pillow, SciPY, Numpy.
 
 **Prerequisites:** To work with Tensorflow on Taurus, you obviously need
-[access](../access/login.md) for the Taurus system and basic knowledge about Python, SLURM system.
+[access](../access/ssh_login.md) for the Taurus system and basic knowledge about Python, SLURM system.
 
 **Aim** of this page is to introduce users on how to start working with
 TensorFlow on the \<a href="HPCDA" target="\_self">HPC-DA\</a> system -

doc.zih.tu-dresden.de/mkdocs.yml

@@ -7,13 +7,13 @@ nav:
     - Request for Resources: application/request_for_resources.md
     - Project Request Form: application/project_request_form.md
     - Project Management: application/project_management.md
-  - Access to the Cluster:
+  - Access to ZIH Systems:
     - Overview: access/overview.md
+    - Connecting with SSH: access/ssh_login.md
+    - Key Fingerprints: access/key_fingerprints.md  
     - Desktop Visualization: access/desktop_cloud_visualization.md
     - Web VNC: access/web_vnc.md
-    - Login via SSH: access/ssh_login.md
     - Security Restrictions: access/security_restrictions.md
-    #- SSH with Putty: access/ssh_mit_putty.md
     - JupyterHub:
       - JupyterHub: access/jupyterhub.md
       - JupyterHub for Teaching: access/jupyterhub_for_teaching.md