"Everything fails, all the time," so says Amazon.com CTO Werner Vogels.
Amazon Web Services itself experienced a much publicized four-day service disruption last April, another outage in August and it had plenty of company from other cloud service companies last year. Microsoft's Windows Azure cloud platform in February had downtime problems due after the company failed to account for Leap Day, and despite improvements by cloud providers to minimize future outages, more outages will inevitably happen this year and beyond.
[ The Amazon outage was one year ago: Are we safer? | In the data center today, the action is in the private cloud. InfoWorld's experts take you through what you need to know to do it right in our "Private Cloud Deep Dive" PDF special report. | Also check out our "Cloud Security Deep Dive," our "Cloud Storage Deep Dive," and our "Cloud Services Deep Dive." ]
Here are steps experts say enterprise IT shops should take to avoid cloud outages from knocking them out:
1) With AWS, use multiple availability zones.
Amazon Web Services offers "availability zones" (AZ) in each of its regions and for each of its services. The company describes AZs as each running on its own physically distinct, independent infrastructure. "They are physically separate, such that even extremely uncommon disasters such as fires, tornados or flooding would only affect a single Availability Zone." During last year's outage, about 45 percent of customers who used only a single AZ for the Relational Database Services were impacted, compared to less than 3 percent of customers who used a multi-AZ approach, AWS said in a post mortem report. After last year's outage the company made it easier for customers to use a multi-AZ approach by allowing common design and APIs to distribute instances across AZs.
2) With AWS, use multiple regions.
AWS has a network of eight regions including: US East (Northern Virginia), US West (Oregon), US West (Northern California), EU (Ireland), Asia Pacific (Singapore), Asia Pacific (Tokyo), South America (Sao Paulo), and AWS GovCloud. For extra security and protection beyond a multi-AZ approach, users can place workloads in multiple regions. It's not quite as easy as putting workloads in multiple AZs though, as separate APIs calls are needed for the different regions.