Public IP
Overview contacts Cloudflare China HTTPS trace to observe the public IP and family used by that request. One request does not independently test IPv4 and IPv6. First appearance and manual refresh may send it.
SUPPORT / DIAGNOSTICS
Understand every network check.
Distinguish DNS, TCP, TLS, public IP and IPv4/IPv6 path status.
IPv4/IPv6 path
Shows iOS path capability, not a guarantee that a particular site or VPN endpoint is reachable.
DNS lookup
Gives the hostname to the current iOS resolver. Success means the name resolved, not that a port connects.
TCP connection
Attempts the specified host and port. It checks basic reachability, not website content or a VPN handshake.
TLS diagnostics
Attempts a secure handshake. Failure can involve certificate, hostname, TLS version, proxy or server configuration.
Changing results
Carrier routing, resolver, firewall, captive Wi-Fi, network handoff, server load and timeout can change a result.
Common errors
Timeout means no completion within the limit; DNS failure means the name did not resolve; refused means the host answered but the port did not accept.