It\u2019s hard to stay on top of everything all the time so it\u2019s understandable that something like renewing a security certificate could fall through the cracks as it did to Microsoft last week, grinding its Azure Cloud Service to a halt.But if you provide a critical service to corporate customers, \u00a0routine updates - \u00a0like renewing certificates before they expire \u2013 ought to be just another routine part of doing business, details that gets taken care of in a routine way.BACKGROUND: Microsoft's Azure service hit by expired SSL certificate\u00a0 RELATED: Microsoft Azure overtakes Amazon's cloud in performance test\u00a0Apparently if there was such a routine it somehow broke down. Microsoft says is still sorting out what went wrong in order to prevent something similar from happening in the future.Meanwhile businesses using Azure Cloud Service should reevaluate how much they entrust to it. They should have done this in the first place before buying the service, but even if they did it doesn\u2019t hurt to review based on the outage.Business-critical data that must be accessible all the time clearly does not belong in the Azure cloud unless it\u2019s also available someplace else.\u201cAll the time\u201d is a tall order, something that even private storage could fail to achieve. The standard for most service providers \u2013 established by phone companies \u2013 is 99.999% uptime. That means downtime of just 25.9 seconds per month.Microsoft\u2019s SLA for Azure Storage Service kicks in when the monthly uptime percentage drops to 99.9%, which means downtime of 43.8 minutes per month. At that point customers are eligible for a 10% service credit, according to Microsoft\u2019s SLA\u00a0for the service.If uptime drops to 99% - which translates to 7.2 hours per month downtime \u2013 customers are entitled to a 25% credit. Friday's outage was so bad that Microsoft says it will waive the requirement that customers report that service failures within 5 business days. The company is automatically crediting affected customers, according to a Microsoft blog written by Steven Martin the general manager of Windows Azure Business & Operations.According to Microsoft\u2019s timeframe the outage lasted from 3:44 p.m. Eastern Friday to 4 a.m. Eastern Saturday when more than 99% of customers had service restored. That\u2019s about 11 hours, 16 minutes of downtime, which is below the 99% threshold for awarding a 25% service credit.Getting a credit is great as far as it goes, but SLAs don\u2019t prevent downtime. They just give providers an incentive to minimize it, and as this case shows they don\u2019t always succeed. Azure had another outage\u00a0just about a year ago for different reasons and affecting just its management services.These two events don\u2019t condemn Azure services, but they should encourage customers to carefully consider what types of data these services are appropriate for and what types they are not.(Tim Greene covers Microsoft for Network World and writes the Mostly Microsoft blog. Reach him at\firstname.lastname@example.org\u00a0and follow him on\u00a0Twitter\u00a0https:\/\/twitter.com\/#!\/Tim_Greene.)More on Microsoft:Windows 8 guru names the top 8 trends at CES\u00a0Windows 8 portables to get inexpensive, long-lived by Xmas 2013?\u2018Christmas gift for someone you hate: Windows 8\u2019Rumored follow-ons for Surface tablets; reduced orders for original SurfaceMicrosoft buys a starring role for its Surface tablet on TV\u2019s 'Suburgatory'Microsoft bets the farm on Metro\u00a0Windows Server 2012 isn't available yet, but it's running BingIs Google taking a run at Windows 8?This Windows 8 tablet might actually be a PCDemise of Cius offers lessons for Windows 8Why aren\u2019t Apple and Amazon dumping on Windows RT?