Hewlett Packard cloud services have better service level agreements than Amazon, according to a Gartner analyst. But she said that both companies could improve to comprehensibility of their agreements.
Writing in a blog post, Research vice president Lynda Leong said that most significant difference between the SLAs is that the HP’s SLA is intended to cover a single-instance failure.
“Where you can’t replace that single instance; AWS requires that all of your instances in at least two availability zones be unavailable,” said Leong. “HP requires that you try to re-launch that instance in a different availability zone, but a failure of that launch attempt in any of the other availability zones in the region will be considered downtime.”
Leong said that users do not need to be running instances in two availability zones all the time in order to get the SLA. “For the purposes of the SLA clause requiring two availability zones, the launch attempt into a second availability zone counts.”
Leong said that HP begins counting downtime when, post-instance-failure, a user makes the launch API call that is destined to fail. “Downtime begins to accrue six minutes after you make that unsuccessful API call,” said Leong. But added that when the downtime clock stops is unclear.
But she said that both companies fail in the intelligibility of their service level agreements.
“The best don’t even need examples for illustration, although it can be useful to illustrate anything more complicated,” she said. “Both HP and AWS sin in this regard, and frankly, many providers who have good SLAs still force you through a tangle of verbiage to figure out what they intend.”
She added that most customers are fundamentally interested in solution SLAs — ’is my stuff working’, regardless of what elements have failed.
“Even in the world of cloud-native architecture, this matters — one just has to look at the impact of EBS (Elastic Block Store ) and ELB (Elastic Load Balancing) issues in previous AWS outages to see why,” said Leong.
