Web Application

The Virtual Cluster can be accessed by any standard web browser such as Mozilla Firefox, Google Chrome, Safari, or Edge by entering the URL of the Virtual Cluster frontend in the address bar.

A login page is displayed where the user credentials provided by the system administrator should be entered (see image). Please confirm that the connection to the login page is showing HTTPS and that your browser doesn’t indicate any problem with the certificate of the web application. Please contact your system administrator if your browser displays any warning indicating issues with the security of the connection to the Virtual Cluster.

If two-factor authentication is enabled on your system the following dialog is shown on first login.

Any authenticator application can be used as a second factor. Common examples for authenticator applications are:

Once the correct credentials are provided, a selection menu with available session types (graphical or terminal) is displayed or, if only one session type is associated with your user account, the connection to the session available to your account is established directly.

Note

It may need up to two minutes for the desktop of a graphical session to appear as an appropriate instance type needs to be started by the backend.

Data Transfer#

The web application can handle data transfer between the Virtual Cluster and the client via clipboard and file transfer.

Clipboard#

Clipboard content can be transferred seemlessly between the client and the remote instance if the web browser supports the Asynchronous Clipboard API which most modern browsers do. If your browser does not support this API, you can use the text box in the sidebar to share clipboard content (see image). The sidebar is shown when pressing Ctrl+Alt+Shift.

File Upload#

To upload a file to the home directory on the Virtual Cluster simply drag and drop a file onto the session window in the browser (this will upload the file to your home directory on the Virtual Cluster). Alternatively, activate the sidebar by pressing Ctrl+Alt+Shift. The file transfer controls appear in the sidebar of the session window (see image). Click on “Devices” in the sidebar and navigate to the folder to which you want to upload the file(s). Then click on “Upload Files” and select the file(s) on your client you would like to upload in the dialog which opens.

File Download#

Activate the sidebar by pressing Ctrl+Alt+Shift. Click on “Devices” in the sidebar and navigate to the folder from which you want to download file(s). Currently, it is only possible to download files, but not a whole folder. In order to download all files located in a certain folder and its subfolders you can enter the command:

zip -r -9 <folder-name>.zip <path-to-folder>

in a terminal on the virtual desktop (or directly if you’re logged in using a terminal session) and replace with the name of the folder you would like to download and with the full path to the folder in the file system on the Virtual Cluster. This creates an archive with all files and folders located in . The resulting archive will be created in the current working directory (usually your home directory). This archive can be downloaded and unpacked on the client. Alternatively, when using the graphical desktop, you can open the file manager and navigate to the folder which you would like to compress. Right-click on the folder and select “Compress…” and the type of archive you would like to create. This creates an archive containing the contents of the folder and is equivalent to the command shown above. Now double-click on the file/archive in the file manager of the sidebar to start the download process.

Note

If the archive doesn’t show up when it has been created, click the refresh button in your browser. After reloading the page, reopen the sidebar and navigate to the folder containing the archive.

Data transfer section of the sidebar. This allows to transfer text between local and remote clipboards as well as files.

Logging Out#

To log out of a session, press Ctrl+Alt+Shift and select “Logout” from the dropdown menu. This will delete the session token.

Note

Closing the browser tab with the web application does not log out a user. Another person using the same local user account on the client is able to access the session simply by re-opening the browser tab or by entering the URL of the Virtual Cluster. Although the session token is invalidated after a certain time of inactivity, always log out explicitly to prevent any unprivileged access to the Virtual Cluster. This is especially true when using any public, unprotected internet connection to access the Virtual Cluster, e.g. in a hotel, etc.