Just five months after storms took down Amazon-powered sites such as Instagram, Pinterest and Netflix, issues at Amazons Northern Virginia datacenter gave Amazon Web Services customers fits on Monday.

The outage started around 2:11pm Eastern Time, and affects a small number of instances in Amazon Web Servicess US-EAST-1 Region.

According to AWS Service Help Dashboard, the Northern Virginia data center is experiencing Degraded EBS performance in a single Availability Zone that appeared to take down or severely degrade performance of sites including Reddit, Flipboard, Airbnb, and Github.

To be fair, Mondays downtime appears to be from actual issues with the servers themselves. Junes disruption and an August 2011 incident at the same datacenter were due to power outages.

As of Monday night, Amazon said it restored normal performance to about half of the instances affected, although it did not say how long it would be before service was fully restored.

These downtime periods arent just frustrating for companies providing the affected Web-based services; increasingly, its becoming an issue for Internet users. A third of us now access a site that uses Amazon Web Services as its backend at least once a day, according to a recent DeepField Networks survey.