ACL configuration restrictions and guidelines
Matching packets are forwarded through slow forwarding if an ACL rule contains match criteria or has functions enabled in addition to the following match criteria and functions:
Source and destination IP addresses.
Source and destination ports.
Transport layer protocol.
ICMP or ICMPv6 message type, message code, and message name.
Logging.
Time range.
Slow forwarding requires packets to be sent to the control plane for forwarding entry calculation, which affects the device forwarding performance.