We did a very interesting upgrade today on RunSignUp. In technical terms, we added something called Session Replication. And we did this across two Amazon Availability Zones by duplicating our memcache session servers.
What this means is that if one of Amazon’s Cloud data centers goes out, users are automatically switched to the other data center without even noticing. This is also very useful for us when we do upgrades to the system – where we can bring one set of servers down to upgrade them and users will never even notice.
This is part of our service our users will never see. And it might only impact our users a few hours per year. But there is nothing we won’t do to make sure we make life simpler for runners, race directors and timers!
