Cisco Catalyst 3550

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Catalyst 3550 Multilayer Switch Command Reference
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Chapter 2 Catalyst 3550 Switch Cisco IOS Commands
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Command Modes Privileged EXEC
Command History
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.
option (Optional) Keyword signifying IP options are present in the packet.
icmp icmp-type icmp-code Internet Control Message Protocol (ICMP) parameters. The icmp-type
and icmp-code ranges are 0 to 255.
igmp igmp-version igmp-type Internet Group Management Protocol (IGMP) parameters. The
igmp-version and igmp-type ranges are 0 to 255.
tcp src-port dst-port flags 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.
udp src-port dst-port User Datagram Protocol (UDP) parameters. The src-port and dst-port
ranges are 0 to 65535.
cos cos (Optional) Class of service (CoS) value of the frame. The range is 0 to
1024.
arpa ethertype (Optional) Address Resolution Protocol (ARP) Ethernet II
encapsulation type and the Ethertype field. The range is 0 to 65535.
snap snap_type (Optional) Subnetwork Access Protocol (SNAP) encapsulation type
and the Ethertype field. The range is 0 to 65535.
sap lsap (Optional) Service access point (SAP) encapsulation type and the
LSAP field. The range is 0 to 65535.
| begin (Optional) Display begins with the line that matches the expression.
| exclude (Optional) Display excludes lines that match the expression.
| include (Optional) Display includes lines that match the specified expression.
expression Expression in the output to use as a reference point.
Release Modification
12.1(4)EA1 This command was introduced.