A developer receives this message when testing a new external website:This site cannot be reached.

Firewall logs are the best starting point because the error indicates that the website cannot be reached from the network path. A firewall may be blocking outbound traffic, inbound return traffic, DNS-related access, specific ports, or the destination IP/domain. Firewall logs can show denied connections, rule matches, source and destination addresses, ports, protocols, timestamps, and policy decisions. IDS logs generally detect suspicious traffic but do not normally enforce blocking. Application logs are useful after the application is reachable, but the symptom here is connectivity failure. System logs may show local host issues, but they are less directly tied to external access controls. For Security+ troubleshooting, network access failures often require checking firewall policy and traffic logs first.