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    CESNET Data Storage 
    ===================
    
      
    
    Introduction
    ------------
    
    Do not use shared filesystems at IT4Innovations as a backup for large
    amount of data or long-term archiving purposes.
    
    The IT4Innovations does not provide storage capacity for data archiving.
    Academic staff and students of research institutions in the Czech
    Republic can use [CESNET Storage
    service](https://du.cesnet.cz/).
    
    The CESNET Storage service can be used for research purposes, mainly by
    academic staff and students of research institutions in the Czech
    Republic.
    
    User of data storage CESNET (DU) association can become organizations or
    an individual person who is either in the current employment
    relationship (employees) or the current study relationship (students) to
    a legal entity (organization) that meets the “Principles for access to
    CESNET Large infrastructure (Access Policy)”.
    
    User may only use data storage CESNET for data transfer and storage
    which are associated with activities in science, research, development,
    the spread of education, culture and prosperity. In detail see
    “Acceptable Use Policy CESNET Large Infrastructure (Acceptable Use
    Policy, AUP)”.
    
    The service is documented at
    <https://du.cesnet.cz/wiki/doku.php/en/start>. For special requirements
    please contact directly CESNET Storage Department via e-mail
    [du-support(at)cesnet.cz](mailto:du-support@cesnet.cz).
    
    The procedure to obtain the CESNET access is quick and trouble-free.
    
    (source
    [https://du.cesnet.cz/](https://du.cesnet.cz/wiki/doku.php/en/start "CESNET Data Storage"))
    
    CESNET storage access
    ---------------------
    
    ### Understanding Cesnet storage
    
    It is very important to understand the Cesnet storage before uploading
    data. Please read
    <https://du.cesnet.cz/en/navody/home-migrace-plzen/start> first.
    
    Once registered for CESNET Storage, you may [access the
    storage](https://du.cesnet.cz/en/navody/faq/start) in
    number of ways. We recommend the SSHFS and RSYNC methods.
    
    ### SSHFS Access
    
    SSHFS: The storage will be mounted like a local hard drive
    
    The SSHFS  provides a very convenient way to access the CESNET Storage.
    The storage will be mounted onto a local directory, exposing the vast
    CESNET Storage as if it was a local removable harddrive. Files can be
    than copied in and out in a usual fashion.
    
    First, create the mountpoint
    
        $ mkdir cesnet
    
    Mount the storage. Note that you can choose among the ssh.du1.cesnet.cz
    (Plzen), ssh.du2.cesnet.cz (Jihlava), ssh.du3.cesnet.cz (Brno)
    Mount tier1_home **(only 5120M !)**:
    
        $ sshfs username@ssh.du1.cesnet.cz:. cesnet/
    
    For easy future access from Anselm, install your public key
    
        $ cp .ssh/id_rsa.pub cesnet/.ssh/authorized_keys
    
    Mount tier1_cache_tape for the Storage VO:
    
        $ sshfs username@ssh.du1.cesnet.cz:/cache_tape/VO_storage/home/username cesnet/
    
    View the archive, copy the files and directories in and out
    
        $ ls cesnet/ 
        $ cp -a mydir cesnet/.
        $ cp cesnet/myfile .
    
    Once done, please remember to unmount the storage
    
        $ fusermount -u cesnet
    
    ### Rsync access
    
    Rsync provides delta transfer for best performance, can resume
    interrupted transfers
    
    Rsync is a fast and extraordinarily versatile file copying tool. It is
    famous for its delta-transfer algorithm, which reduces the amount of
    data sent over the network by sending only the differences between the
    source files and the existing files in the destination.  Rsync is widely
    used for backups and mirroring and as an improved copy command for
    everyday use.
    
    Rsync finds files that need to be transferred using a "quick check"
    algorithm (by default) that looks for files that have changed in size or
    in last-modified time.  Any changes in the other preserved attributes
    (as requested by options) are made on the destination file directly when
    the quick check indicates that the file's data does not need to be
    updated.
    
    More about Rsync at
    <https://du.cesnet.cz/en/navody/rsync/start#pro_bezne_uzivatele>
    
    Transfer large files to/from Cesnet storage, assuming membership in the
    Storage VO
    
        $ rsync --progress datafile username@ssh.du1.cesnet.cz:VO_storage-cache_tape/.
        $ rsync --progress username@ssh.du1.cesnet.cz:VO_storage-cache_tape/datafile .
    
    Transfer large directories to/from Cesnet storage, assuming membership
    in the Storage VO
    
        $ rsync --progress -av datafolder username@ssh.du1.cesnet.cz:VO_storage-cache_tape/.
        $ rsync --progress -av username@ssh.du1.cesnet.cz:VO_storage-cache_tape/datafolder .
    
    Transfer rates of about 28MB/s can be expected.