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PASSEDvoip / zoom_phone_failover_failure
Zoom Phone Failover Failure — PSTN Survivability Lost
Zoom Phone cloud service experiences an outage during a severe weather event that also knocks out the primary internet circuit. The Zoom Phone Survivability Gateway (local appliance) fails to activate because it was never properly configured after installation. The office has no phone service — cloud calling is down and local failover doesn't work.
Pattern
TIMEOUT
Severity
CRITICAL
Confidence
95%
Remediation
Remote Hands
Test Results
| Metric | Expected | Actual | Result |
|---|---|---|---|
| Pattern Recognition | TIMEOUT | TIMEOUT | |
| Severity Assessment | CRITICAL | CRITICAL | |
| Incident Correlation | Yes | 21 linked | |
| Cascade Escalation | N/A | No | |
| Remediation | — | Remote Hands — Corax contacts on-site support via call, email, or API |
Scenario Conditions
Zoom Phone cloud PBX. 200 Zoom Phone users. Primary internet circuit down (weather). Backup circuit congested. Zoom Phone Survivability Gateway installed but not configured. No local PSTN fallback. Complete telephony outage.
Injected Error Messages (2)
Zoom Phone cloud service unreachable — primary internet circuit down due to severe weather, timeout connecting to Zoom Phone cloud, all cloud-based calling features offline, 200 users unable to make or receive calls, secondary internet circuit too congested for real-time voice
Zoom Survivability Gateway failover failed — local gateway zsg-01 not activating, timeout on cloud registration check, gateway configuration incomplete (SIP trunk not provisioned), local PSTN breakout not configured, survivability mode not engaging, complete telephony outage with no failover path, timeout on all call attempts
Neural Engine Root Cause Analysis
The primary internet circuit has failed due to severe weather conditions, making the Zoom Phone cloud service unreachable. The secondary internet circuit is available but experiencing congestion that makes it unsuitable for real-time voice communications, which require low latency and high quality of service. This infrastructure-level connectivity issue is preventing 200 users from accessing cloud-based calling features, with 10 correlated incidents suggesting a broader network impact affecting multiple services simultaneously.
Remediation Plan
1. Contact ISP immediately to report primary circuit outage and request expedited repair ETA. 2. Implement emergency traffic shaping on secondary circuit to prioritize voice traffic over other services. 3. Consider temporary failover to backup connectivity solutions (cellular, satellite, or alternate ISP). 4. Communicate service disruption to affected users with timeline estimates. 5. Monitor secondary circuit performance and implement QoS policies if technically feasible. 6. Evaluate long-term redundancy improvements to prevent similar outages.
Tested: 2026-03-30Monitors: 2 | Incidents: 2Test ID: cmncjstk104cqobqe618cjqlm