The Scholarly Data Archive (SDA) at Indiana University

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System overview

The Indiana University Scholarly Data Archive (SDA) provides extensive capacity (approximately 42 PB of tape overall) for storing and accessing research data. The SDA is a distributed storage service co-located at IU data centers in Bloomington and Indianapolis, providing IU researchers with large-scale archival or near-line data storage, arranged in large files, with two copies of data made by default (for disaster recovery).

The SDA is based on the High Performance Storage System (HPSS), a consortium-developed hierarchical storage management (HSM) package that makes the SDA's hierarchy of storage media transparent to its users. The SDA's system architecture comprises fast, efficient disk cache front-end components (with a capacity of roughly 1,800 TB) that move infrequently accessed data to two high-end tape libraries (with nearly 15 PB of capacity). Using the I-Light high-performance network between IUB and IUPUI, the SDA creates two tape copies of user data simultaneously (one at each data center), adding a degree of disaster tolerance to both sites.

The SDA is well suited for storing large volumes of data (i.e., tens of gigabytes to several terabytes per project), and data that are accessed relatively infrequently (i.e., archival or near-line storage). The SDA backend is not designed for storing a large number of small files. Individual files should be at least 1 MB. If you need to store many small files on the SDA, use a file compression utility (e.g., gzip, tar, or zip) to bundle your files into a single, large archive file.

The SDA supports high-performance access methods, such as the Hierarchical Storage Interface (HSI); an HPSS API is available for programmers, as well.

Note: At IU, the initials SDA, MDSS, and HPSS are often used interchangeably to describe the same service.

System information

Note: The SDA is offline for regularly scheduled maintenance every Sunday 7am-10am.

System configuration
Machine type Distributed HPSS data archive
Operating system Red Hat Enterprise Linux 6
Storage information
Network file system protocols
HSI/HTAR, CIFS (Samba) as read-only, SFTP/SCP, HTTPS
Usable tape capacity 15 PB
Total disk capacity (cache) 1800 TB
50 TB (default) per user, 50 TB (default) per project; increases as needed
Backup and purge policies
Dual copies of data, but no backups; system is never purged
Aggregate I/O 80 Gbps

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Working with data containing PHI

The Health Insurance Portability and Accountability Act of 1996 (HIPAA) established rules protecting the privacy and security of individually identifiable health information. The HIPAA Privacy Rule and Security Rule set national standards requiring organizations and individuals to implement certain administrative, physical, and technical safeguards to maintain the confidentiality, integrity, and availability of protected health information (PHI).

This system meets certain requirements established in the HIPAA Security Rule that enable its use for research involving data that contain protected health information (PHI). You may use this resource for research involving data that contain PHI only if you institute additional physical, administrative, and technical safeguards that complement those UITS already has in place. For more, see When using UITS Research Technologies systems and services, what are my legal responsibilities for protecting the privacy and security of data containing protected health information (PHI)? If you need help or have questions, contact UITS HIPAA Consulting.

Although PHI is one type of institutional data classified as Critical at IU, other types of institutional data classified as Critical are not permitted on Research Technologies systems. Except for PHI, the most sensitive classification of institutional data allowed on Research Technologies resources is Restricted. For help determining which institutional data elements classified as Critical are considered PHI, see Which data elements in the classifications of institutional data are considered protected health information (PHI)?

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Requesting an account

For eligibility requirements, see the "Research system accounts (all campuses)" section in What computing accounts are available at IU, and for whom?

If you (or your group) are eligible to request an SDA account, but it is not listed among the accounts available to request, contact your campus Support Center for help.

After submitting your account request, UITS will notify you via email when your account is ready for use.

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Access and transferring files

Once you have an SDA account, you can access it from any networked host. The method you use depends on your operating system and level of comfort with the command-line interface.

Methods available for transferring data to and from the Indiana University Scholarly Data Archive (SDA) include Hierarchical Storage Interface (HSI), secure FTP (SFTP), secure copy (SCP), https (via a web browser), and the IU Cyberinfrastructure Gateway (CI Gateway). For instructions, see:

Read-only access is available via CIFS/Samba; see At IU, how do I access the SDA via Samba?

HSI, the highest performing non-grid method, provides shell-like facilities for recursive operations, and can take input data from standard input. HSI also can perform file migration to tape, stage files from tape to disk, and purge files from the disk cache.

HSI is available on UITS research computing systems when you load the hpss module; for more about Modules, see On Big Red II, Karst, and Mason at IU, how do I use Modules to manage my software environment?

For use on personal workstations, Linux, OS X, and Windows versions of the HSI/HTAR bundle are available from UITS Research Storage; to request a copy, contact UITS Research Storage.

For Windows or OS X users who prefer a graphical interface, UITS recommends using a graphical SFTP client. For OS X users, particularly those needing to transfer large amounts of data, UITS recommends Fetch (available from IUware).


See On the Scholarly Data Archive at IU, what are classes of service, and how do I use them?

Acknowledging grant support

The Indiana University cyberinfrastructure, managed by the Research Technologies division of UITS, is supported by funding from several grants, each of which requires you to acknowledge its support in all presentations and published works stemming from research it has helped to fund. Conscientious acknowledgment of support from past grants also enhances the chances of IU's research community securing funding from grants in the future. For the acknowledgment statement(s) required for scholarly printed works, web pages, talks, online publications, and other presentations that make use of this and/or other grant-funded systems at IU, see If I use IU's research cyberinfrastructure, what sources of funding do I need to acknowledge in my published work?

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The SDA is maintained by the Research Storage team. If you have questions or need help, contact Research Storage.

This is document aiyi in the Knowledge Base.
Last modified on 2016-11-17 10:58:52.

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