Wiss. Rechnen » Workspaces

The cluster has a central file system with about 60 TB of disk storage space. The file system is the same from every login and compute node.

Home directory

Any user automatically gets a home directory, into which you can put your data. This directory has the path /home/<YourUsername>. The size of your home directory is limited to 100 GB.

Daily backups are made of all home directories, the backups are deleted after 30 days. If you lose files in your home directory, you can change to the directory /home/.snapshot. In that directory you can find the daily backups (snapshots), each in its subfolder. You can simply copy files that you want to restore back to your normal home directory:

$ cd ./home/.snapshot/daily_<Datum>_0010/<Your Username> 
$ cp <File or files> <Your home directory>


$ cd /home/.snapshot/daily.2020-08-04_0010/demo_user/ 
$ cp file1 file2 /home/demo_user

To copy entire folders with their content (recursively) use the option -r. Please note that existing data at the target location may potentially be overwritten. The cp command offers options like e.g. -i to give you more control over this. You can show the help with man cp.

Example: Copy folder exampledir back to home and confirm overwriting for every file:

$ cd /home/.snapshot/daily.2020-08-04_0010/demo_user/ 
$ cp -i -r exampledir /home/demo_user

Example: Restore all deleted files in folder exampledir without overwriting any existing files

$ cd /home/.snapshot/daily.2020-08-04_0010/js056demo_user352/ 
$ cp -n -r exampledir /home/demo_user


For your compute jobs it is recommended not to use the home directory but rather to create a so-called workspace. This has two advantages: first, there is no size limit for workspaces, and second, the workspaces are located physically on another hard drive with a faster connection to the compute nodes. Workspaces have a limited duration: after the workspace expires, it is deleted. You can extend this duration up to three times.

Create and extend workspaces

You can create a new workspace with the command

$ ws_allocate <WS name> <duration>

where the duration has to be given in days. The maximum possible duration without extensions is 30 days.

Caution: if you leave out the duration, the workspace will only be allocated for one day.

The workspace will be created in a subdirectory of /work/ws-tmp/ and its name consists of your username and the workspace name specified by you. The workspace is available like any other folder with the cd command. In the following example:

$ ws_allocate test1 4 
Info: creating workspace. 
remaining extensions : 3 
remaining time in days: 4

you can see that a workspace named test1 with an initial duration of 4 days has been created and is available via cd /work/ws-tmp/demo_user-test1.

If you want to extend an existing workspace, you need to enter

$ ws_extend <WS name> <duration>

with the name of an existing workspace and a new duration. You can extend the duration three times, by a maximum of 30 days each time. If you enter the name of a workspace that does not exist, it will be created as if you had used ws_allocate.

The ws_allocate command also has some additional features which you can see with man ws_allocate.

E-Mail notifications

The workspace mechanism can send you an e-mail before a workspace expires.

We recommend that you always use this function to avoid data losses.

The corresponding command is then:

$ ws_allocate <WS name> <duration> -r <number of days> -m <your e-mail address>

With the option -m you can specify the e-mail address and with -r you specify how many days before expiration you want to be warned. If you do not want to re-enter your e-mail address every time you can put a text file named .ws_user.conf in your home directory. In that file you write your address according to the following example:

mail: demo_user@uni-siegen.de

Note that there needs to be a space after the colon (YAML syntax).

You can also create a calendar entry with

$ ws_send_ical <WS name> <e-mail address>

List your workspaces

You can list your existing workspaces by entering

$ ws_list

Release (delete) a workspace

If you do not need a workspace any more, you can release it. Caution: all data in this workspace will be unavailable from that point on.

To do that you can use the command

$ ws_release <Workspace name>

Restore a deleted workspace

As mentioned above, expired workspaces are not available any more, but they are not completely deleted immediately. The data inside a workspace will be kept for 10 days, even after the workspace expired or was released, before being deleted completely. Therefore it is possible to restore the data if a workspace expired accidentally. To do that, follow these steps:

  1. You can list your expired workspaces via:
    $ ws_restore -l 
     unavailable since Tue Jun 12 09:30:01 2018
  2. Create a new workspace:
    $ ws_allocate <new-workspace> <duration>
  3. Restore the expired workspace with the command ws_restore inside the new workspace. For that, you need the complete name of the old workspace (which includes your user name and an ID number), which you can get via ws_restore -l:
    bash $ ws_restore <user>-<old-workspace>-<number> <new-workspace>

    The new workspace will contain the old one in a subdirectory.

  4. Type the displayed text. This serves to make automatic workspace restoration impossible.


Aktualisiert um 17:41 am 12. August 2018 von Jan Philipp Stephan