Domain-based split tunneling behaves fundamentally differently from traditional access-route-based split tunneling: where access-route tunneling operates purely through entries in the local operating system routing table, domain-based split tunneling is implemented through a filter driver on Windows and a network extension on macOS that intercepts and redirects connections dynamically as domains are resolved and matched, rather than by inserting static host routes the administrator or user can simply read from a routing table. Because the enforcement mechanism itself lives inside this filter driver/extension rather than in visible routing entries, the documented, reliable way to confirm the configuration has actually been pushed correctly and is being applied as expected is to collect detailed, dump-level GlobalProtect application logs, which expose the filter driver ' s internal decision-making for the specified domain - this is precisely option B, and it matches Palo Alto Networks ' own published troubleshooting guidance for this feature. Checking the routing table (option A) is the correct verification method for route-based (access-route) split tunneling, but it is explicitly documented as not reflective of domain-based split tunnel behavior, since no corresponding static route is guaranteed to appear there. Verifying DNS resolution alone (option C) confirms name resolution occurred, but not that the filter driver actually applied the correct include/exclude action to the resulting session. Pinging the domain (option D) is unreliable because split-tunneling rules apply to TCP/UDP traffic and explicitly do not govern ICMP, so a ping result does not validate split-tunnel enforcement at all.
Reference:GlobalProtect - Troubleshoot Split Tunnel Domain and Application Configuration.