The microblogging service Tumblr came back online late Monday after approximately 24 hours of downtime. The problems started during a scheduled maintenance window, in which a database cluster failed and a network outage followed. An account of the incident posted on the Tumblr staff blog said the outage was precipitated by unexpected events, but also acknowledged that Tumblr is struggling to manage its site traffic.
"Frankly, keeping up with growth has presented more work than our small team was prepared for — with traffic now climbing more than 500M pageviews each month,"the Tumblr team wrote. "But we are determined and focused on bringing our infrastructure well ahead of capacity as quickly as possible. We’ve nearly quadrupled our engineering team this month alone, and continue to distribute and enhance our architecture to be more resilient to failures like today’s."