Deep Packet Inspection (DPI) is not supported; The firewall service is available only for dedicated servers; A server cannot be added to the firewall if it: is already assigned to another firewall, belongs to an L2 segment in native mode, is configured without a public network; Each rule can include up to 1,000 addresses; IPv6 support is not available at this time; The service is available in specific locations only; Limited compatibility with L2 segments