It's a well-known fact in the IT world: Change one part of the software stack, and there's a good chance you'll have to change another. For a shining example, look no further than big data.
First, big data shook up the database arena, ushering in a new class of "scale out" technologies. That's the model exemplified by products like Hadoop, MongoDB, and Cassandra, where data is distributed across multiple commodity servers rather than packed into one massive one. The beauty there, of course, is the flexibility: To accommodate more petabytes, you just add another inexpensive machine or two rather than "scaling up" and paying big bucks for a bigger mammoth.
That's all been great, but now there's a new sticking point: backup and recovery.
"Traditional backup products have challenges with very large amounts of data," said Dave Russell, a vice president with Gartner. "The scale-out nature of the architecture can also be difficult for traditional backup applications to handle."
Today's horizontally scalable databases do include some capabilities for availability and recovery, but typically they're not as robust as those IT users have become accustomed to, Russell added.
It's a problem that can leave large enterprises vulnerable when outages strike. But it's also where a new class of data-protection products is beginning to enter the picture.
Datos IO's RecoverX is one of those.
"If you have a traditional database like Oracle or MySQL, it's scale-up, and there's always the notion of a durable log," said Tarun Thakur, Datos IO's co-founder and CEO.
In such scenarios, a copy of that log is what constitutes a backup when problems arise.
In the world of today's next-generation databases -- where data is distributed across small machines -- it's not quite so simple.
"There is no concept of a durable log because there is no master -- each node is working on its own stuff," Thakur explained. "Different nodes could get different rights, and every node has a different view of an operation."
That's in part because of a trade-off that's been required to accommodate what's commonly referred to as the "three V's" of big data -- volume, velocity, and variety. Specifically, to offer scalability while accommodating the crazy amounts of diverse data flying at us at ever-more-alarming speeds, today's distributed databases have departed from the "ACID" criteria generally promised by traditional relational databases. Instead, they've adopted what are known as "BASE" principles.
It's a critical distinction. Most pertinent is that where traditional databases promise strong consistency throughout -- that's the "C" in ACID -- distributed ones strive instead for what's called "eventual consistency." Updates will be reflected in all nodes of the database sooner or later, but there's a time lag.
Sign up for MIS Asia eNewsletters.