Hear that? The wikis go silent twice a year
- Benoît Evellin is a Senior Movement Communications Specialist (Product & Tech), and Ana Eira is a Movement Communications Specialist, for the Wikimedia Foundation.
When you click the "edit" button on a wiki, you're likely focused on improving the content. The process feels seamless: edit, save, repeat. From patrolling new edits to uploading photos or joining a campaign, you can count on the Wikimedia platform to be up and running—in your language, anywhere in the world. That is, except for a couple of minutes during the equinoxes.
Twice a year, around the equinoxes, the Wikimedia Foundation's Site Reliability Engineering (SRE) team performs a datacenter server switchover, redirecting all traffic from one primary server to another—essentially a backup. But why? In case of a crisis we can rely on the other datacenter.
The scheduled switchover process allows for essential maintenance and improvements at the backup center. It also allows the team to test their procedures, minimize the impact of the read-only time, and work on the overall reliability of the sites.
Thanks to Listen to Wikipedia, a playful tool that turns each edit into a sound and visualizes it as a floating bubble in real-time, you can actually hear the switchover take place. Before the switchover starts, you will hear the steady stream of edit sounds. But then—about 2 minutes in—the sound stops, which means the system has entered the read-only phase. And when the sounds start up again? That's the moment engineers can finally breathe—it's the clear signal that the toughest part of the switchover is done and edits are flowing again. Watch this video to experience that extraordinary moment.
This rare interruption happens because all Wikimedia wikis rely on a server designed specifically for their needs and managed by the Wikimedia Foundation. This setup allows us to remain independent, while delivering a reliable experience for users around the world.
The SRE team oversees a global network of datacenters, seven in total, spanning the United States, Singapore, the Netherlands, France, and, most recently, Brazil. These datacenters allow articles and other content to load quickly, securely, and privately, to be accessed anywhere and anytime.
At the heart of this network are the two application server groups which host the live copies of the projects. Having two application server groups is necessary to keep all the wikis we host alive: if one server fails, the second one can take over, and vice-versa. With an estimated 342 edits per minute happening on Wikipedia alone, having a backup server is a must.
While the switchover may sound simple, the reality is that the process has evolved significantly over the years.