Services for Object Storage and Preservation

March 2008

All content in these slides is considered work in progress. In no way does it represent an absolute view of any final end product and at this stage should purely be considered a set of realistic ideas.

OutlineStorageTek 5800 (The Honeycomb) provides

high resilience data storage with a built in metadata layer.

EPrints is a piece of repository software for managing large collections of digital objects and their related metadata.

EPrintsOpen Source repository software to provide open

access to institutional output.

Provides a powerful plugin based package which can easily be extended at any layer to suit a users requirements.

2 types of archive

Those used to manage publications and small objects.Those used to deposit large objects. These tend to

contain heavier customisation.

Preserv2Preserv2 is the 2nd iteration of a project looking

at preservation services for repositories.

Beyond simple backupFormat Renderers, Format Translation,

Risk Assessment, Interoperability and long term storage.

Why use a Honeycomb?A Honeycomb is not just a “Big Disk”

A Service Based Architecture:Big object, big storage, more powerful

plugins/services.Smaller Repositories can jointly use a single

Honeycomb as a “Preservation Service”.

Preservation Service ProvidersCan combine several servers into a “Honeycomb

Cloud”

EPrints Architecture

EPrints (Repository) Layer

Object Storage Metadata Storage

EPrints and Honeycomb

EPrints (Repository) Layer

STK5800HoneyComb

Services for Repositories

EPrints (Repository) Layer

Metadata Services

Storage Beans

Automated Wide Area

Backup

Metadata ServicesSame resilience as data.

Averts the need to store a file id/url somewhere in order to find an object.

Enables collections to be constructed by independent parties.

Objects can be exported into many formats accurately.

Storage BeansCan perform operations upon the objects in the

system without reliance upon the repository to manage these processes. (e.g. Object Translation)

Preservation services can provide feedback to repository administrators on potential risks to their objects. (e.g. Object Classification, age)

Can be used to extend the metadata layer to provide more powerful access to objects and their parts/pages. (e.g. Retrieve me page 10 of volume 6 of X)

Wide Area Replication (Backup)

The possibility to link two or more Honeycombs together over a wide area to provide mirrored backup.

This can be implemented by the archive which can store its objects in a “Honeycomb Cloud”

Possible Architectures (2)

Repository Repository Repository

Possible Architectures (3)

Repository Repository Repository

Possible Architectures (4)

Repository Repository Repository

Preservation ServicesA “Honeycomb Cloud” provides the basis for a

preservation service which can be provided to many small scale (<200Gb) repositories.

Options for object storage: Locally with Honeycomb acting purely as a preservation

service. Hand all object storage and retrieval to Honeycomb Cloud. A half and half solution:

Small Objects served locally, Large Objects from Honeycomb.

Recent and Popular Objects served locally, Older Objects considered preserved.

The out of the box repository solution for Large Repositories.

Thumpers “Big Disk”The Thumper system (STK 4500) is essentially a

“Big Disk” server.

“Out of the Box” solution.

Expansions:Services to enable replication between 2 thumpers.Preservation services using a Honeycomb.

Aimed at Repositories where tape backup is not ideal.

Ecrystals (Possible Use Case)Large Chemistry repository which currently stores

only processes result objects (small).

These result files are generated from >1Gb raw datasets.

8+ Datasets generated a day.

After 6 months results sets are of less worth.This represents 1TB of raw data in a 6 month period.

ECrystals – Single Honeycomb ArchitectureCurrent Repository

RemainsAll Results Sets Stored on

HoneyComb

ProsSimplistic ArchitectureSole use of HoneycombYear of “on-site” storage.

ConsCostBackup Procedure?

EPrints (Repository) Layer

“

Thumper System

“

Thumper System

ECrystals – Thumper with “Honeycomb Cloud”

ProsSingle local machine6 months+ locally Accessible

Automated Preservation

Preservation Services managed by Honeycomb Cloud.

Storage Beans on Honeycomb Cloud compress older/less popular objects

Cons?

EPrints (Repository) Layer

SummaryHoneycomb provides:

Better separation of repository layer from storage layer.

Repository interoperability.A new approach to storing and preserving data

from institutional repositories based on EPrints and other software.