One of CIOs' biggest concerns about the infrastructure-as-a-service model has been the loss of control over assets and management that enterprises might experience upon moving into a multi-tenant environment. While analysts and early adopters of infrastructure-as-a-service offerings have argued that such apprehension is rooted more in fear than fact, Amazon's recent public data centre debacle has given everyone good reason to question the reliability of the public cloud.
The two-day outage may not slow the long-term growth of cloud computing significantly, but it should cause IT decision makers to pause. Before rushing into any new cloud infrastructure deal, take the following seven steps to mitigate the risk of infrastructure-as-a-service failure.
1. Plan to fail
Develop detailed cloud breakdown scenarios and perform recovery run-throughs. "Put your risk-mitigation strategy firmly in place before moving into the cloud environment," says Phil Fersht, founder of outsourcing analyst firm HfS Research.
Heather McKelvey, vice-president of engineering and operations for Mashery, an API management services provider, agrees. "A lot of people think 'get it up and running' and then we'll put in the design for failover," she says. "You can't do that. [Others] assume that a cloud will failover to another cloud-or one data centre to another data centre-but there are varying degrees of where problems can happen, and you need to architect and build for all levels of failure in your system, not just the high level."
2. Keep some expertise in house
One of the allures of cloudsourcing is the notion that you no longer have to maintain internal knowledge of the technologies that support as-a-service solutions. However, captive know-how comes in handy when you need to prepare for and react to cloud problems. "I don't see CIOs having much option but to increase in-house knowledge of cloud underpinnings," Fersht says.
If you lack in-house capabilities, ask your provider for help, or consider hiring consultants to create a disaster recovery and business continuity plan. "Even a small investment in third-party risk oversight is worth the investment, if it helps negate a potential disaster in the event of a long outage," Fersht says.
3. Test that plan - then test it again
"The cloud is the perfect place to test failures in a completely staged environment," says Donald Flood, vice-president of engineering for Bizo, a business-to-business advertising network provider and Amazon Web Services customer. "You can easily create a staged environment that mirrors production and test your systems by killing running services and evaluating how your system performs under failure."
4. Create internal back-up options
It took about two days for Amazon to locate and repair the problems at its data centre in northern Virginia. But as soon as US Tennis Association CIO and Amazon Elastic Cloud Compute (EC2) customer Larry Bonfante began to notice application sluggishness, he and his team migrated the USTA's critical systems to their own server. IT leaders must maintain internal contingency capabilities, Bonfante advises.
5. Reexamine your sourcing strategy
IT leaders have embraced multi-sourcing, but that model can make cloud continuity confusing. "The domino-effect ramifications of an outage are very complex to manage and resolve," says Fersht. For example, as more services get built on top of cloud computing infrastructures, a seemingly isolated outage can have a domino effect, taking down many services or an entire application environment, he adds.
Putting one service integration provider in charge of a multi-sourced arrangement will give you "one throat to choke" in the event of a failure, according to Fersht, but it can also prove problematic. "They are likely to develop an institutional knowledge of your IT processes that would be very tough to transfer in the future if you wanted to maintain a healthy competitive environment," Fersht says. "You need to have your own IT staff get smart about how cloud works, or you really do risk potentially losing control over your own IT environment."
6. Don't be cheap
The ROI of redundancy investments skyrockets in cloud collapse scenarios. Many of the companies affected by Amazon's failure could not-or would not-pay to run parallel systems in the cloud. However, major Amazon Web Services customer Netflix says it experienced no issues because its cloud computing model assumed one of the data centres in Amazon's four regions would go down. The company had "taken full advantage of Amazon Web Services' redundant cloud architecture", a Netflix spokesperson told The New York Times.
Critical data should be replicated across multiple availability zones (Amazon's term for a regional data centres) and backed up or live replicated across regions; active servers should be distributed geographically, and there should be enough active capacity to shift locations should one data centre implode, advises Thorsten Von Eicken, CTO and co-founder of cloud management vendor RightScale. "Of course all this has costs, so each business needs to determine which costs are justified for each service being offered," he adds.
For example, Bizo runs its services in two availability zones in each of the four Amazon regions it utilises. When the eastern region went south last week, the company redirected that traffic to the western region.
7. Put your provider on the hook
Make sure your cloud vendors have some skin the game with a contract that ties outages to service levels. "If they [CIOs] are subcontracting to a third-party cloud provider, ensure they are responsible for these outages and can't [absolve] themselves of responsibility," Fersht says.