#envoy

DevOps & CI/CD Bug Report

Istio 503 "upstream connect error" in the first seconds of every pod: app started before the proxy

Sofia Andersson · Oct 14, 2026 · 7 min read

After adding Istio to our EKS cluster, every rollout produced a burst of failures: startup jobs could not reach the database and calls returned 503 upstream connect error. The application started before its Envoy sidecar was ready. How we proved it and fixed it with native sidecars and holdApplicationUntilProxyStarts.

Performance & Scaling Bug Report

Retry storm without jitter: how a 20-second database blip became a 41-minute outage

Daniel Tran · Jun 5, 2025 · 10 min read

A routine database failover lasted 20 seconds, but our API stayed down for 41 minutes. Three layers each made up to three attempts with no delay, multiplying load on the database by 27. Here is the math, the fix and how we proved it.