Earlier, Yammer had a service disruption at 19:53 PDT on 6/20/2012 was caused by an attempt to update to our messaging service. We began the software update at 19:39 PDT. At 19:53 PDT our monitoring system reported site performance issues.
We quickly identified that the rate we were rolling out the software update resulted in diminished capacity to the point that the site was unable to respond to requests. We decided the most expedient way to resolve the site issue was to accelerate the update and fully restart the messaging service. Service was completely restored by 20:36 PDT. No data was lost as a result of the update or site issues.
To prevent future outages we will be modifying our software update procedures to ensure that we have sufficient capacity.