Recently the SNIA XAM SDK TWG (Software Development Kit Technical Working Group) released a new version (version 0.7) of the XAM SDK with lots of new features. Included in this SDK was the 5th code drop for the Reference VIM. Here is a summary of the major new functionality included in this code drop. Support for XSet hold and release Support for XSet autodelete and shred policies Support for simple where clauses in level 1 queries Support for retention policies including XSet import and export Support for asynchronous methods Support for level 2 queries Also recently released were version 1.01
While experimenting on how to prototype a Cloud XAM Storage System using Amazon Web Services (AWS), I experimented with the Amazon SimpleDB service using Java and the Typica AWS client library. I looked though the Internet for easy examples of how to use this library but found none that I liked – so here is my attempt at a tutorial on using the Typica library with the Amazon SimpleDB service. To use the Typica library, you should download the latest version of the library. As of the date of this post it is typica.1.6. Install this library wherever you like;
As well as providing vendor-independent means of creating, retrieving, modifying and deleting XSets, the SNIA XAM v1.0 specification also defines a query language (XAM QL), based on a subset of the SQL language, for selecting and retrieving the XUIDs of XSets based on content-defined criteria. The set of reserved words for this query language is quite small: select, where, and, or, not, like, exists, binding, readonly, typeof, length, date, TRUE, FALSE, before, after, contains, and within. By design, XAM queries look like an SQL select statement. The query language is case insensitive and uses the ASCII character set. Here is
In this post I look at what fields are mandated by the SNIA XAM v1.0 specification and write a small Java application to retrieve their default values using the XAM Reference VIM and EMC’s Centera XAM VIM. What is meant by a field in XAM? According to Section 3.1.5 of the XAM specification v1.0, Part 1, a field is a piece of uniquely identifiable data that can be attached to an XSet, an XSystem, or a XAM Library. More concretely, a field has a name, a number of attributes that describe how to interact with the object, and a value.
One of the key requirements for achieving long term data persistence is the ability to move data between archiving systems or, in the language of the SNIA XAM (eXtensible Access Method) specification, moving XSets between XSystems. The XAM v1.0 specification supports this requirement by providing support for exporting and importing Xsets. It specifies the methods used to export an XSet from an XSystem, the resultant XSet canonical data interchange format (package) and the methods used to import an Xset into an Xsystem. This post assumes that you are somewhat familiar with XAM and how to program to that specification using