Remote replication, a critical part of business continuity

Australia’s recent flooding raises significant questions about business continuity - especially as the US Government Geological Survey predicts a superstorm of biblical proportions that could put the state of California under ten feet of water. How can companies protect against scenarios like these?

Remote replication involves backing up data between different sites, and there are various ways to accomplish it. Host-based replication replicates between individual servers, and can even focus on particular applications. There are both strengths and weaknesses to this approach. On the one hand, backing up individual servers within a large enterprise that has lots of servers can lead to unwanted complexity, and can easily lead to data duplication, which makes inefficient use of WAN bandwidth. On the other hand, it can be a useful way to prioritize individual servers that are mission-critical and need priority recovery times, rather than waiting in a queue while a whole storage infrastructure is restored.

Array-based replication partly solves the management problem, because it deals with whole storage arrays at once, making it easier to deal with a large ‘bucket’ of storage as a single entity. The downside is that array-based storage management products often need a storage array from the same vendor at either end of the link, which limits an IT department’s procurement choices.

Site-based replication using an appliance at the edge of the network provides the most flexibility when it comes to remote replication. These solutions are vendor-independent, and can cope with a cluster of arrays. They are also well suited to data de-duplication, because they ‘see’ data from the site’s entire storage infrastructure.

Some companies are offering cloud-based replication, where they copy a customer’s data into their own cloud infrastructure, using a site-based appliance at the customer’s premises. This can represent an attractive solution for customers hoping to minimize capital expenditure.

However a company chooses to do it, remote replication is a critical part of business continuity, and should be considered - especially as the possibility of floods and other extreme weather conditions increases.

Anthony Plewes

After a Masters in Computer Science, I decided that I preferred writing about IT rather than programming. My 20-year writing career has taken me to Hong Kong and London where I've edited and written for IT, business and electronics publications. In 2002 I co-founded Futurity Media with Stewart Baines where I continue to write about a range of topics such as unified communications, cloud computing and enterprise applications.