Vercel Multi-AZ and Multi-Region Failover Explained

Last year we announced the Vercel Dubai region (𝚍𝚡𝚋𝟷) on AWS 𝚖𝚎-𝚌𝚎𝚗𝚝𝚛𝚊𝚕-𝟷. A region is made up of multiple availability zones (AZs). The AWS availability zone 𝚖𝚎𝚌𝟷-𝚊𝚣𝟸 just got 💥 bombed. Our primary traffic ingress AZ has been unaffected. Fluid functions are also unaffected, because they automatically deploy to multiple AZs and load balance around them. AZs are basically “sub-regions”. They’re designed to have independent power supply, cooling, networking, physical security, fire suppression, and logistical operations. If Dubai’s region got seriously impacted, Vercel automatically reroutes traffic. Fluid functions can deploy to a backup region for automatic failover. So you get multi-AZ and multi-region. In a situation like this, this means citizens being able to access critical information, news, emergency services, and so on. Here’s hoping the situation normalizes as soon as possible and peace prevails 🤞