An Ambient mode troubleshooting appendix covering two Istio and Envoy issues encountered in production.
July 13, 2026#envoy
7 posts
- Istio Part 3-4: Detecting 507 Status Codes and istiod Disconnections
- Istio Part 3-3: Safely Upgrading Ambient Mode
A runbook for upgrading Istio Ambient mode.
July 8, 2026 - Istio Part 3-2: Partially Enrolled Pods and the Untaint Controller
Ambient mode troubleshooting: when Pods are scheduled before istio-cni is ready on a node.
July 2, 2026 - Istio Part 3-1: 503 and Half-open Connections
Ambient mode troubleshooting: 503 errors caused by Envoy reusing stale connections.
June 26, 2026 - Istio Part 2: Ambient Mode Under the Hood via Envoy Configs
A deep dive into how Istio Ambient mode's HBONE tunneling and traffic redirection are implemented in Envoy configs.
April 14, 2026 - Investigating Istio AuthorizationPolicy ext_authz in Envoy Config
Analyzing how Istio AuthorizationPolicy's action: CUSTOM works in Envoy config based on actual envoy config dump.
March 10, 2026 - Identifying Client IP in Istio (Proxy Protocol v2)
How to obtain the real client IP in an AWS NLB + Istio Gateway environment where even numTrustedProxies doesn't help, solved with Proxy Protocol v2.
April 2, 2025