===== Connecting to the cluster(s) =====

Access to cluster resources is provided via secure shell (SSH) login.

Most Unix-like operating systems (Mac OS X, Linux, etc) provide an ssh utility by default that can be accessed by typing the command ssh in a terminal window.
  * Note that you can only connect to these servers via SSH when you have a 130.89* address. Which means you have to be on campus or logged in via **[[https://utwente.nl/vpn|eduVPN]]**.

You can login to one of the head nodes of these clusters.
Check the Cluster specific pages for the current head node, see the **[[:start#Usage|Usage Page]]**.

Note : 
  * Login nodes are not intended to be used for computationally intensive work.

==== Linux & Mac ====

To login to a headnode from a Linux or Mac computer, open a terminal and at the command line enter:

<code bash>$ ssh <UserId>@<NodeName>.ewi.utwente.nl</code>

Note :
  * replace **<UserId>** with your login name, **<NodeName>** with one of the listed login nodes.
  * replace ewi with the appropriate faculty name

==== Windows ====

Windows users will first need to download an ssh client which will allow you to interact with the remote Unix command line. When setting up your connection to the cluster, use the following information:

<code bash>
Hostname: <NodeName>.ewi.utwente.nl
Port:     22
Username: <UserID>
Password: <Password>
</code>

Use one of the following clients :
  * [[https://mobaxterm.mobatek.net/|MobaXterm]] (Windows)
  * [[https://www.microsoft.com/en-us/p/windows-terminal/9n0dx20hk701?activetab=pivot:overviewtab|Windows Terminal]] (Windows)
  * [[https://www.chiark.greenend.org.uk/~sgtatham/putty/|Putty]] (Windows)

===== X11 applications =====

To display the gui applications on your desktop, you need to enable (trusted) X11 forwarding. When connecting through ssh, add the "-Y" parameter.

<code bash>$ ssh -Y <UserId>@<NodeName>.ewi.utwente.nl</code>

Windows users needs to set this option in the used application (Putty : Session Configuration->Connection->SSH->X11->Enable X11 forwarding).

Use one of the following clients :
  * [[https://mobaxterm.mobatek.net/|MobaXterm]] (Windows)
  * [[https://sourceforge.net/projects/xming|Xming@sourceforge]] or [[http://www.straightrunning.com/XmingNotes/index.php|Xming@straightrunning]] (Windows)
    * **Xming v7.7 (donated version) available on request.**
  * [[https://www.xquartz.org|XQuartz]] (Mac OS/X)

To allow the remote computer to display on your workstation, either use the **xhosts** command or add the remote server to the X0.hosts file, this will authorize displaying on your computer.

===== Data transfer (SCP) =====

Secure copy or SCP is a means of securely transferring computer files between a local host and a remote host. It is based on the Secure Shell (SSH) and Secure File Transfer (SFTP) protocols.

==== Command-Line Operation: ====

Most UNIX-like operating systems (Mac OS X, Linux, etc) provide a scp command which can be accessed from the command line. To transfer files from your local computer to your home directory on the cluster, open a terminal window and issue the command:

  * Single files:
<code bash>$ scp <some file> <UserID>@<NodeName>.ewi.utwente.nl:</code>
  * Directories:
<code bash>$ scp -r <some dir> <UserID>@<NodeName>.ewi.utwente.nl:</code>
  * Or to a directory on the cluster (/deepstore/project2, for example) :
<code bash>$ scp -r <some dir> <UserID>@<NodeName>.ewi.utwente.nl:/deepstore/project2</code>

When prompted, enter your password.

==== GUI Clients: ====

Thera are gui based tools as well, a few are listed below :
  * **[[https://mobaxterm.mobatek.net/|MobaXterm]]** (windows only)
  * **[[http://www.winscp.net|WinSCP]]** (windows only)
  * **[[https://filezilla-project.org|FileZilla]]** (mac/linux/windows)
  * **[[https://cyberduck.io|Cyberduck]]** (mac/windows)
  * nautilus(ubuntu)
  * etc.