Merge branch 'login' into 'preview'

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See merge request zih/hpc-compendium/hpc-compendium!175

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

 # Login to the High Performance Computers
 
-The best way to login to the linux machines is via ssh. From a Linux
-console, the command syntax is `ssh user@host`. The additional option
-\<span>-X\</span>C enables X11 forwarding for graphical applications
-(the -C enables compression which usually improves usability in this
-case).
+The best way to login to the Linux machines is via ssh. From a Linux console, the command syntax is
+`ssh user@host`. The additional option `-XC` enables X11 forwarding for graphical applications (the
+`-C` enables compression which usually improves usability in this case).
 
 The following table gives an overview of all clusters.
 
-| Hostname                  | Description         |
+| Host name                  | Description         |
 |:--------------------------|:--------------------|
 | taurus.hrsk.tu-dresden.de | BULL system - SLURM |
 
-**Attention:** For security reasons, this port is only accessible for
-hosts within the domains of TU Dresden. Guests from other research
-institutes can use the
+**Attention:** For security reasons, this port is only accessible for hosts within the domains of 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. Information on these topics can be found on our web
-pages <http://www.tu-dresden.de/zih>.
+gateway of the ZIH. Information on these topics can be found on our web pages
+<http://www.tu-dresden.de/zih>.
 
 ## Access from a Windows workstation
 
-We suggest Windows users use MobaXTerm. **TODO Link MobaXterm**. 
+We suggest Windows users use MobaXTerm. **TODO Link MobaXTerm**.
 Benefits of MobaXTerm include:
 
--   easy to use
--   graphical user interface
--   file transfer via drag and drop
+- easy to use
+- graphical user interface
+- file transfer via drag and drop
 
-## Access from a Linux workstation
+## Access from a Linux Workstation
 
-### SSH access
+### SSH Access
 
-**Attention:** 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>*
+**Attention:** 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`
 
 If your workstation is within the campus network, you can connect to the
 HPC login servers directly, e.g., for Taurus:
 
-    ssh <zih-login>@taurus.hrsk.tu-dresden.de
+```Bash
+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 the fingerprint:
 
-``` bash
+```Bash
 user@pc:~# 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.
@@ -54,26 +52,32 @@ 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".
 
-<span class="twiki-macro TABLE" caption="Fingerprints"></span>
-
-| Host                                                                                                                                                                              | Fingerprint                                                                                                                                                                                                                                                                                                                                                                                                    |
-|:----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|:---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
-| tauruslogin3.hrsk.tu-dresden.de\<br />tauruslogin4.hrsk.tu-dresden.de\<br />tauruslogin5.hrsk.tu-dresden.de\<br />tauruslogin6.hrsk.tu-dresden.de\<br />taurus.hrsk.tu-dresden.de | SHA256:/M1lW1KTOlxj8UFZJS4tLi+8TyndcDqrZfLGX7KAU8s (RSA)\<br />SHA256:PeCpW/gAFLvHDzTP2Rb93NxD+rpUsyQY8WebjQC7kz0 (ECDSA)\<br />SHA256:nNxjtCny1kB0N0epHaOPeY1YFd0ri2Dvt2CK7rOGlXg (ED25519)\<br /> or:\<br /> MD5:b8:e1:21:ed:38:1a:ba:1a:5b:2b:bc:35:31:62:21:49 (RSA)\<br />MD5:47:7e:24:46:ab:30:59:2c:1f:e8:fd:37:2a:5d:ee:25 (ECDSA)\<br />MD5:7c:0c:2b:8b:83:21:b2:08:19:93:6d:03:80:76:8a:7b (ED25519) |
-| taurusexport.hrsk.tu-dresden.de\<br /> taurusexport3.hrsk.tu-dresden.de\<br /> taurusexport4.hrsk.tu-dresden.de                                                                   | SHA256:Qjg79R+5x8jlyHhLBZYht599vRk+SujnG1yT1l2dYUM (RSA)\<br />SHA256:qXTZnZMvdqTs3LziA12T1wkhNcFqTHe59fbbU67Qw3g (ECDSA)\<br />SHA256:jxWiddvDe0E6kpH55PHKF0AaBg/dQLefQaQZ2P4mb3o (ED25519)\<br /> or:\<br />MD5:1e:4c:2d:81:ee:58:1b:d1:3c:0a:18:c4:f7:0b:23:20 (RSA)\<br />MD5:96:62:c6:80:a8:1f:34:64:86:f3:cf:c5:9b:cd:af:da (ECDSA)\<br />MD5:fe:0a:d2:46:10:4a:08:40:fd:e1:99:b7:f2:06:4f:bc (ED25519)  |
+| 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) |
 
 From outside the TUD campus network
 
-Use a VPN (virtual private network) to enter the campus network, which
-allows you to connect directly to the HPC login servers.
+Use a VPN (Virtual Private Network) to enter the campus network, which allows you to connect
+directly to the HPC login servers.
 
-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).
+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).
 
 ### Access using JupyterHub
 
-A JupyterHub installation offering IPython Notebook is available under:
-
-<https://taurus.hrsk.tu-dresden.de/jupyter>
+A JupyterHub installation offering IPython Notebook is available under
+https://taurus.hrsk.tu-dresden.de/jupyter
 
 See the documentation under [JupyterHub](../access/jupyterhub.md).