Cisco Catalyst 3550 Command Reference Manual page 298

show forward
option
icmp icmp-type icmp-code
igmp igmp-version igmp-type Internet Group Management Protocol (IGMP) parameters. The
tcp src-port dst-port flags
udp src-port dst-port
cos cos
arpa ethertype
snap snap_type
sap lsap
| begin
| exclude
| include
expression
Command Modes
Privileged EXEC
Command History Release
12.1(4)EA1
Usage Guidelines If you enter this command without any arguments, you enter a dialog mode. This mode is not operational
in this release.
Because of the many and varied items that go into the forwarding decision, this command requires
detailed information about the frame in order to correctly indicate how the hardware would forward the
frame.
This command has limited ability to account for QoS settings. It does not take into account any packet
arrival rates, so if the system has been configured to mark down or police traffic based on data arrival
rates, the command will display inaccurate information for traffic that exceeds the configured rates.
If QoS or ACLs are not configured, and if no port-channel interfaces are present, the most important
parameters to specify are source interface, source VLAN, destination MAC address, and destination IP
address (if applicable). The output is likely to be accurate, even if other parameters are missing or
estimated.
If port channel interfaces are present, it is important to specify the source MAC address and IP address
correctly.
Catalyst 3550 Multilayer Switch Command Reference
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(Optional) Keyword signifying IP options are present in the packet.
Internet Control Message Protocol (ICMP) parameters. The icmp-type
and icmp-code ranges are 0 to 255.
igmp-version and igmp-type ranges are 0 to 255.
Transmission Control Protocol (TCP) parameters: TCP source port,
destination port, and the numeric value of the TCP flags byte. The
src-port and dst-port ranges are 0 to 65535.
User Datagram Protocol (UDP) parameters. The src-port and dst-port
ranges are 0 to 65535.
(Optional) Class of service (CoS) value of the frame. The range is 0 to
1024.
(Optional) Address Resolution Protocol (ARP) Ethernet II
encapsulation type and the Ethertype field. The range is 0 to 65535.
(Optional) Subnetwork Access Protocol (SNAP) encapsulation type
and the Ethertype field. The range is 0 to 65535.
(Optional) Service access point (SAP) encapsulation type and the
LSAP field. The range is 0 to 65535.
(Optional) Display begins with the line that matches the expression.
(Optional) Display excludes lines that match the expression.
(Optional) Display includes lines that match the specified expression.
Expression in the output to use as a reference point.
Modification
This command was first introduced.
Chapter 2 Cisco IOS Commands
78-11195-09