Why are there multiple 408 errors in App Platform's runtime logs?

Multiple 408 errors are often caused by your app sending health checks with very short timeouts to App Platform. They typically don’t affect the functionality of the app.

Some apps, especially PHP apps, send health checks that time out before App Platform responds, and this causes the 408 error. You can’t prevent the 408 errors from appearing in the runtime logs because you can’t filter or suppress the health checks.

Dedicated egress IPs route egress (outbound) traffic from an app. To route ingress (inbound) traffic to an app, use one of App Platform’s public ingress IPs.
Add the root domain to the list of domains in the app’s settings along with the wildcard subdomain.
App Platform apps may be slow or unable to resolve .gov domains because the domain administrators have blocked DigitalOcean’s IP addresses. To fix this, you can contact the domain administrator or use a custom DNS resolver.