Google: 100 percent uptime 'not attainable'

Removal of downtime clause for scheduled maintenance and revised downtime count part of company's efforts to give customers greater assurance, not a promise to deliver absolute uptime, says spokesperson.

Google's recent tweaks to its service level agreement (SLA) is not a promise to deliver 100 percent uptime but rather, an initiative to provide greater assurance for its customers, clarifies a company spokesperson.

In a blog post dated Jan. 17, Matthew Glotzbach, enterprise product management director for Google, announced that the Internet giant is improving its SLA for Google Apps by removing a previous clause that allows for scheduled downtime.

When contacted, a company spokesperson clarified that this means customers can expect no downtime of Google Apps services when Google is performing upgrading or maintenance work on its systems, but it is not claiming it can provide absolute service uptime.

"[Google doesn't] believe that 100 percent uptime is attainable with commercial services. For comparison, even the landline telephone doesn't reach 100 percent uptime", she told ZDNet Asia in an e-mail.

She noted that there will be occasions of unforeseen and unexpected downtime, pointing to exclusions listed in the Google Apps SLA. For example, a service may experience downtime from factors constituting "Force Majeure", such as natural disasters and acts of war or terrorism.

Previously, the Google Apps SLA would not recognize intermittent downtime of less than 10 minutes. This has now been removed. "Now any intermittent downtime is counted", said Glotzbach in the blog entry.

The revisions in the SLA mean higher assurance of lesser downtime because Google now counts downtime of any reason, planned or unplanned, into its SLA, the spokesperson said.

She added that what remains unchanged in the SLA is that Google's services will achieve at least 99.9 percent uptime in any calendar month. If its services drop below 99.9 percent for the month, customers will receive service credits in return. Service credits are days of service added to the end of the customer's contract.

Glotzbach wrote that Google will, hence, "eliminate maintenance windows from their service level agreement (SLA)", and is the first major cloud provider to do so.

Asked to respond to Google's SLA changes, a Microsoft spokesperson said in an e-mail: "Microsoft Online Services offer the most rigorous financially-backed SLAs. We guarantee 99.9 percent uptime, or we give customers money back."

When contacted, cloud service providers Amazon Web Services and declined comment.