SAN disaster recovery planning
What would be a feasible and, most importantly, cost effective disaster recovery solution for an environment that uses SAN infrastructure. (Assumption is that due to cost constraints, management may or may not employ similar infrastructure thus, may not be able to supplicate the production SAN infrastructure on the disaster recovery site).
As always, determining what constitutes a cost effective disaster recovery solution to your organization is the key. Some of the least expensive solutions may include elements such as host based data replication over an IP network to a remote and dissimilar SAN technology. As an alternative, storage virtualization is gaining acceptance and can allow the replication of data, across a SAN and to dissimilar storage arrays. There are other combinations and variations of the above but essentially, we always have to first define what cost effective means.
The value and importance of the data to the business should always be the starting point in designing a data protection scheme. The Recovery Time Objective (RTO) helps determine the type of data replication technology required by telling how quickly backup data must be accessible. The Recovery Point Objective (RPO) indicates whether synchronous or asynchronous data replication is the right choice.
As difficult as it sometimes can be to sell this idea to management, organizations should always determine the value of their data before deciding what is an acceptable cost to protect it.
This was first published in April 2005