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  • alias: data.marconi.cineca.it
  • hostnames and IPs:
    • dmover1.marconi.cineca.it - 130.186.17.140
    • dmover2.marconi.cineca.it - 130.186.17.141

Marconi100:

  • alias: data.m100.cineca.it
  • hostnames and IPs:
    • dmover1.m100.cineca.it - 130.186.16.214
    • dmover2.m100.cineca.it - 130.186.16.215

Galileo100:

  • alias: data.g100.cineca.it
  • hostnames and IPs:
    • dmover1.g100.cineca.it - 130.186.16.212
    • dmover2.g100.cineca.it - 130.186.16.213

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  • alias: data.leonardo.cineca.it
  • hostnames and IPs:
    • dmover1.leonardo.cineca.it - 131.175.44.50
    • dmover2.leonardo.cineca.it - 131.175.44.51
    • dmover3.leonardo.cineca.it - 131.175.44.52
    • dmover4.leonardo.cineca.it - 131.175.44.53

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First of all, on datamovers, there is no CPU time limit, that allows long data transfers. Unlike, on login nodes, there is a 10-minute of CPU time limit that usually interrupts the transfer of a large amount of data.
By construction, the shell is not available, so it is not possible to open interactive sessions. In other words you cannot connect directly to the datamover via SSH. The only available commands are scp, rsync, sftp, wget, and curl. For security reasons, the shell is not available, and it is not possible to open interactive sessions.
Like the login nodes.
However, the authentication is still based on SSH protocol. There are only 2 possible authentication methods:

  1.  publickey: it only accepts valid SSH certificates, obtained via 2-Factor Authentication. No private/public keys generated in other ways are accepted.
  2.  hostbased: if you are already logged into a CINECA HPC cluster and try to use a datamover from a login node, the SSH daemon on the datamover recognizes you are already authenticated on a CINECA HPC cluster and that is enough.

Remark: The host-based authentication does is not work enabled inside a job batch. If you want to use a datamover inside a job batch you have to copy a valid 2FA SSH certificate inside your ~/.ssh directory .on the cluster where you are submitting the job batch.

Important: When you are authenticated Finally, when you authenticate yourself on a datamover, you will land on a fake home directory, /home, which is not your true $HOME directory. You can check using sftp, e.g. "sftp <username>@data.leonardo.cineca.it: "
This behavior the environment variables $HOME, $WORK and $CINECA_SCRATCH (as well as ~ or * ) are not defined. 
This property has 2 side effects:

  1. if you want to transfer files FROM/TO your $HOME directory cluster personal areas, you have to specify the absolute path, the same is true for your $WORK, $CINECA_SCRATCH filesystems of them.
  2. You cannot make use of the SSH configuration files stored in your remote ~/.ssh/ directory (~such as $HOME/.ssh/config).

Listing Directory via sftp

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One entered the sftp session, the familiar pwd, cd /path/to/, ls commads commands are available to explore the remote filesystem, together with the sftp command lpwd, lcd /path/to/, lls. You can also transfer data from the sftp session, see the appropriate section below.

At present M100 login nodes are offline, so you need to resort to the sftp command to explore M100 filesystem. For instance:

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Available transfer tools

rsync

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  1. You need to upload or download data FROM/TO your local machine TO/FROM a CINECA HPC cluster
    $ rsync -PravzHS /absolute/path/from/file <username>@data.<cluster_name>.cineca.it:/absolute/path/to/
    $ rsync -PravzHS  <username>@data.<cluster_name>.cineca.it:/absolute/path/from/file /absolute/path/to/
  2. You need to transfer files between 2 CINECA HPC clusters
    $ ssh -xt <username>data<username>@data.<cluster_name_1>.cineca.it rsync -PravzHS /absolute/path/from/file <username>@data.<cluster_name_2>.cineca.it:/absolute/path/to/
    $ ssh -xt <username>data<username>@data.<cluster_name_1>.cineca.it rsync -PravzHS <username>@data.<cluster_name_2>.cineca.it:/absolute/path/from/file  /absolute/path/to/

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  1. You need to upload or download data FROM/TO your local machine TO/FROM a CINECA HPC cluster
    $ scp /absolute/path/from/file <username>@data.<cluster_name>.cineca.it:/absolute/path/to/
    $ scp  <username>@data.<cluster_name>.cineca.it:/absolute/path/from/file /absolute/path/to/


  2. You need to transfer files between 2 CINECA HPC clusters
    $ ssh -xt <username>data<username>@data.<cluster_name_1>.cineca.it scp /absolute/path/from/file <username>@data.<cluster_name_2>.cineca.it:/absolute/path/to/
    $ ssh -xt <username>data<username>@data.<cluster_name_1>.cineca.it scp <username>@data.<cluster_name_2>.cineca.it:/absolute/path/from/file  /absolute/path/to/
  3. You need to transfer files between 2 CINECA HPC clusters using your local machine as a bridge. We strongly suggest not using this option because it has very low transfer performance, each file you move from one cluster to another will pass through your local machine
    $ scp -3  <username>data <username>@data.<clusterr_name_1>.cineca.it:/absolute/path/from/file  data.<cluster_name_2>.cineca.it:/absolute/path/from/file

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There are 2 possible ways to use scp sftp via datamovers:

  1. You need to upload or download data FROM/TO your local machine TO/FROM a CINECA HPC cluster
    $ sftp <username>@data.<cluster_name>.cineca.it:/absolute/remote/path/to/
    sftp> put relative/local/path/to/file
    Uploading /absolute/local/path/to/file to
    /absolute/remote/path/to/file
    file                                                                                                                                                                100%                                                                                                100%  414   365.7KB/s   00:00    
    sftp> get relative/remote/path/to/file
    Fetching /absolute/remote/path/to/file to file
    file
                                                                                                                                                           100% 1455KB  19.0MB/s   00:00    
    sftp> 
  2. You need to transfer files between 2 CINECA HPC clusters
    $ ssh -xt <username>data<username>@data.<cluster_name_1>.cineca.it sftp <username>@data.<cluster_name_2>.cineca.it:/absolute/path/to/

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Sometimes, the 10-minute CPU time limit or the 4-hour wall time limit on the serial queue are is not enough to download a large dataset for ML. In this case, you can use wget from the datamover. Here you can find a simple example

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Sometimes, the 10-minute CPU time limit or the 4-hour wall time limit on the serial queue are is not enough to download a large dataset for ML. In this case, you can use curl from the datamover. Here you can find a simple example

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Datamover nodes of each CINECA HPC cluster host the GridFTP servers. On the datamover we have enabled the authentication via ssh as an alternative to the x509 certificate. Of course, you have to keep in mind that the SSH authentication is based on the ssh certificate, obtained via 2-Factor authentication.

Transfer data between 2 CINECA HPC clusters

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Please refer to GridFTP protocol and globus-url-copy

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client.


Additional transfer modes will be explored and reported in the next future.

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CAVEAT: at present the gsiftp mode is not available on Leonardo.

Transfer data FROM/TO local machine TO/FROM a CINECA HPC cluster

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Please note that authentication via ssh certificate is not available on Globus online