Bab Souk: the entire online shop returns “502 Bad Gateway” in the middle of a sale

Bab Souk, an online marketplace in Casablanca (artisans from Salé, Safi and Essaouira), is launching its big autumn sale today. The site https://www.babsouk.ma goes through an Application Gateway WAF_v2 (agw-babsouk-prod, resource group rg-babsouk-prod, francecentral) in front of a Linux App Service, app-babsouk-prod.

Last night, the platform team merged a “clean-up” of the gateway's Terraform code (renames, addition of a custom health probe on /health). The pipeline went green.

Since 10:00, when the sale opened, every page responds 502. The marketing department has already sent 80,000 text messages. You have the Azure CLI on your workstation, with Contributor rights on the resource group.