---
title: Runbook — DEPENDENCY_CONNECT_FAILED (외부 의존성 연결 실패)
category: TRANSIENT_DEPENDENCY
error_codes: [DEPENDENCY_CONNECT_FAILED]
severity: P1
owner: oncall
last_updated: 2026-06-15
status: stub
---

# Runbook: DEPENDENCY_CONNECT_FAILED (`runbook://dependency/connect-failed`)

## Symptoms

- HTTP 503 with `error.code=DEPENDENCY_CONNECT_FAILED`
- TCP connection refused or network unreachable to upstream

## Diagnosis

- Check `dependency_name` tag for which upstream is unreachable
- Verify network path and firewall rules

## Action

- Check upstream service availability
- Verify service discovery / DNS resolution

## Escalation

- P1 if upstream is a critical service dependency

---

> **Stub**: Phase D2 — author body after domain adoption. (feature-operational-runbook-contract D9)