Ensure your current IP isn't blacklisted by major CDNs.
| Principle | Description | |-----------|-------------| | | Every subnet must have ≥2 routers/switches in an FHRP (First Hop Redundancy Protocol) cluster. | | Failure Domain Isolation | No single power supply, line card, or uplink should kill more than 50% of subnets in a rack/zone. | | Asymmetric Routing Tolerance | Subnets must work even when ingress/egress paths differ (stateful firewalls excepted). | | Hot-Standby State Sync | Active and standby gateways share session/ARP state to avoid connection resets. | fbsubnet l hot