Swestore-dCache

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Swestore is Research Data Storage Infrastructure operated by the Swedish National Infrastructure for Computing (SNIC).

The resources provided by Swestore are made available through open procedures such that the best Swedish research is supported and new research is facilitated. The purpose of Swestore allocations, granted by Swedish National Allocations Committee (SNAC), is to provide large scale data storage for “live” or “working” research data, also known as active research data.

Due to the VR funding, the free allocations on Swestore have some usage limitations.

  • Swestore is NOT supposed to be used for backups and such requests for allocation will be rejected. Please, check with your university (home institution/organisation) IT department about backup services, strategies and policies in place. If such services do not exist or if you can’t access them for different reasons, please contact us at support@swestore.se;
  • Swestore is NOT supposed to be used as archiving service, long-term storage or repository for “static” data. Once data is no longer in the process of change, and decision on which data should be retained shared and/or preserved has been taken, data should be moved toward appropriate data services. The higher education institutions are responsible for archiving and long-term preservation of research data produced by researchers employed by them;
Glossary
Active (Research) data
is data that is being worked on as part of research project and therefore subject to change. The files containing data will need to be accessed and amended or updated as new data is gathered or processed.
Static (Research) data
is data that is no longer in the process of change and it can be prepared for preservation and reuse.
Backup
is a copy of the digital data to be stored and used as a replacement in case the main copy is either deleted or corrupted.
Archive
is a service to record, organise, and store (digital) items in optimal conditions, with standardised labelling to ensure their longevity and continued access. The service is based on application of metadata, archiving policies, records management, and digital preservation actions. Archivists make decisions on selection and retention of items which are usually governed by supporting policies.


Swestore is distributed across the SNIC centres C3SE, HPC2N, Lunarc and NSC. Data is stored in two copies with each copy at a different SNIC centre. This enables the system to cope with a multitude of issues ranging from a simple crash of a storage element to losing an entire site while still providing access to the stored data.

One of the major advantages to the distributed nature of Swestore is the excellent aggregated transfer rates possible. This is achieved by bypassing a central node and having transfers going directly to/from the storage elements if the selected transfer protocol allows it. Swestore can achieve aggregated transfer rates in excess of 100 Gigabit per second, but in practice this is limited by connectivity to the end user, each university or a limited number of files (typically max 1 Gbit/s per file/connection).

To protect against silent data corruption the dCache storage system checksums all stored data and periodically verifies the data using this checksum.

The dCache system does NOT yet provide protection against user errors like inadvertent file deletions.

Getting access to Swestore

Before you can access Swestore you need to be a member of a storage project.

Apply for storage (for the PI)

All normal Swestore projects are managed using the SNIC User and Project Repository portal, SUPR. Please follow the instructions on the Apply for storage on Swestore page to apply for storage.

Apply for project membership (for all users)

All project members must register in SUPR and be added to the approved project by the PI. This can happen in multiple ways:

  • The PI can add you to a project
  • You can request membership to a project:
    • Log in to SUPR
    • Click on the Projects heading in the left hand menu.
    • In the Request Membership in Project section of the page, fill in a project search criteria according to the on-page instructions and click Search for Project
    • Locate the approriate project displayed and click Request button in the Request Membership column.
    • The PI and any Co-PI will be notified of your request and approve/deny as they deem appropriate.

When your project membership is approved by the PI the Swestore system will map an account for you and add access to the project storage directory. Please wait for up to 10 minutes for this information to be distributed to Swestore.

Finding the project storage directory name (for all users)

All Swestore projects are assigned a unique directory name, this is used to locate your storage area.

To find the directory name for a storage project, perform these steps:

  • Log in to SUPR
  • Click on the project ID in the left hand menu.
  • The project Directory Name is shown in the Basic Information section.

The project storage area is available in the path /snic/directory_name/ on Swestore.

Set your Swestore password (for users accessing with username/password authentication)

The username/password access method is the most common authentication method. It requires you to set a password on your Swestore account.

Follow the instruction on the page Setting your Swestore password.

Acquire and manage certificate (for users accessing with certificate authentication)

Certificate authentication is needed in some special cases, and more convenient for use in automation (ie. Robot certificates).

Some communities require certificate authentication and such users might already have a certificate, that certificate is likely good to use with Swestore.

If you need to use Certificate authentication, follow the instruction on the page Certificate Setup for Swestore.

Using Swestore

Download and upload data

From the command line

There are several command line tools capable of using the protocols provided by Swestore. For usage on SNIC clusters we recommend using the ARC tools which should be installed on all SNIC resources.

As an integration point for building scripts and automated systems we suggest using the curl program and library.

Interactive tools
Best suited for interactive use with various support for directory listings, wildcards etc.
Currently no suitable tools to recommend
Command-line tools
These tools are also suitable for scripting or automation.
rclone
Supports multiple protocols.
Swestore-specific documentation not written yet. See upstream documentation at https://rclone.org/webdav/
Use access URL: https://webdav.swestore.se:1443/
cURL
Please see the instructions for Accessing Swestore with cURL. We suggest using this as integration point for building scripts and automated systems.
davix
Swestore-specific documentation not written yet. See upstream documentation at https://davix.web.cern.ch/davix/docs/master/
Use access URL: davs://webdav.swestore.se:1443/
ARC
Certificate authentication only. Supports multiple protocols.
Please see the instructions for Accessing Swestore with the ARC client.
gfal2
Certificate authentication only. Supports multiple protocols.
Swestore-specific documentation not written yet. See upstream documentation at https://dmc.web.cern.ch/projects/gfal-2/documentation
Use access URL: gsiftp://gsiftp.swestore.se/
https://duck.sh/
Command-line client for Windows/macOS/Linux (not documented yet)

Using a GUI client

Graphical User Interface (GUI) clients are known to work on some operating systems.

Cyberduck
Please see the instructions for Accessing Swestore using Cyberduck Recommended method on macOS
WinSCP
Please see the instructions for Accessing Swestore using WinSCP Recommended method on Windows

From a web browser

Swestore is accessible in your web browser as a simple directory index interface at https://webdav.swestore.se/.

Web browser access supports both username/password and certificate authentication.

Projects are organized under the /snic directory as https://webdav.swestore.se/snic/DIRECTORY_NAME/.

JavaScript WebDAV client

Swestore dCache can also be accessed in your browser, through a JavaScript client, over WebDAV at https://webdav.swestore.se/browser/ .

Legacy documentation

There are other clients/methods available, but not recommended for new deployments. See Category:Swestore user guide for a complete list of documentation.

Enabled access protocols

A design criteria for Swestore is to provide the storage over a number of standardized and public protocols. There is no vendor specific client needed for access.

GridFTP
Also called gsiftp. Well supported within Swestore.
Features: Transfer checksums. Direct transfer from/to storage pools for high speed transfers.
Access URL: gsiftp://gsiftp.swestore.se/
HTTP/WebDAV
Contender for being the recommended protocol for Swestore.
Features: Support in web browsers. Supports direct transfer of files from/to storage pools improving performance (varying support in clients).
Authenticated access
This is the normal read-write access.
Access URL: https://webdav.swestore.se/ (non-redirected)
Access URL: https://webdav.swestore.se:1443/ (redirected)
Access URL: https://webdav.swestore.se:2443/ (redirected reads)
Unauthenticated read-only access
For special cases only.
Access URL: http://webdav.swestore.se/ (unauthenticated, read-only, non-redirected)
Access URL: http://webdav.swestore.se:1080/ (unauthenticated, read-only, redirected)
Access URL: http://webdav.swestore.se:2080/ (unauthenticated, read-only, redirected reads)
NFSv4.1
Used by some communities, not recommended for general use
SRM - Storage Resource Manager
Used by some communities, not recommended for general use.
Access URL: srm://srm.swegrid.se/
Xrootd
Used by some communities, not recommended for general use
DCAP
Used by some communities, not recommended for general use

Usage monitoring

Support

If you have any issues using Swestore, please do not hesitate to contact support@swestore.se.

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